Hatz 2-4L30 Workshop Manual

Type plate data Lubricating oil circuit Technical data Sealants and adhesives Special tools and Workshop equipment 2. Additional equipment A 01.00 Fuel A 01.40 Delivery pump with hand pump A 03.00 Exhaust A 03.12 Detaching and attaching enclosure for silencer (muffler) A 04.00 Mechanical starting A 04.10 Crank handle A 04.20 Automatic decompressor A 04.70 Engine rotating device A 04.80 Start release A 05.00 Electric starting A 05.40 Alternator A 07.00 Lubricating oil A 07.10 Lubricating oil cooler, air cooling A 07.11 Lubricating oil cooler, water cooling. A 11.00 Automatic mechanisms A 11.70 Temperature-controlled starting fuel volume regulator A 15.00 Housing A 15.20 Connecting housing A 30.00 Liquid cooling A 30.20 Water pump A 30.40 Thermostat Contents

M 01.00 Crankshaft M 01.10 Balancing weights 2L / 3L M 01.20 Balancing weights, 4L M 01.30 Cleaning crankcase, installing injector nozzles M 02.00 Crankshaft M 04.00 Camshaft M 04.10 Camshaft for valve timing M 04.20 Camshaft for injection pump M 04.30 Governor and injection timer M 05.00 Conrod M 06.00 Piston and cylinder M 06.10 Air-cooled engines M 06.20 Water-cooled engines M 07.00 Cylinder head M 07.10 Air-cooled engines M 07.20 Cylinder head repairs (air-cooled engines) M 07.30 Water-cooled engines M 07.40 Cylinder head repairs (water-cooled engines) M 10.00 Oil pump M 11.00 Timing case cover M 12.00 Starting charge M 12.10 with injection pump PFR 1K 80 M 12.20 with injection pump PFR 1K 90 M 12.30 with injection pump PFR 1K 90 from serial No. L/M31.12, M40.16, 2L40.19, 3-4L40.18 and L/M41 M 13.00 Fan M 14.00 Fuel injection equipment M 14.00 Injection pump, functional test M 14.10 with injection pump PFR 1K 80 M 14.20 with injection pump PFR 1K 90 M 14.30 Injector M 14.40 Injector nozzle M 14.50 Adjusting work with injection pump PFR 1K 80 M 14.60 Adjusting work with injection pump PFR 1K 90 M 17.00 Flywheel M 20.00 Engine shutdown device, belt tensioner M 22.00 Air cleaner M 31.00 Crankcase breather M 32.00 Speed control M 32.10 with injection pump PFR 1K 80 M 32.20 with injection pump PFR 1K 90 M 35.00 Enclosure 4. Tables Tightening torques Repair data Fuel injection equipment and adjusting values Governors Lubricating oil contents and dipstick Key to circuit diagrams HATZ wiring identification Circuit diagrams Trouble-shooting table for the electrical system Contents

(month / year). It has been compiled in such a way that a trained mechanic can perform all repair work correctly. Instructions such as „Clean parts“ etc. have been omitted, as they are assumed to be self-evident. All work must be carried out only with the specified tools or with others of absolutely equivalent quality. It is assumed that the normal hand tools will be available, even if not called for specifi- cally in this manual. Please refer to the operating manual for details of routine maintenance work, operating fluids and materials, troubleshooting etc. Use only genuine HATZ spare parts in repair work. Comply also with generally or locally valid legislation and with the instructions issued by trade associations or accident insurers. The details provided here may differ if special equipment is installed. Please appreciate that neither the workshop manual nor the spare parts list can take all such deviations into account. If problems occur, please contact the nearest HATZ service point.

Governor and exhaust side 1 L / M . . 10.98 Starter and flywheel side Engines: 2 - 4 L . . S / Z 1 Lub.-oil filling and dipstick 2 Speed control lever 3 Exhaust silencer 4 Oil drain plug 5 Lub.-oil filter 6 Engine cover 7 Side panel 8 Cooling fan with built-in alternator 9 Cooling fan drive belt 10 Hydraulic belt tensioner 11 Stop device 12 Governor housing 13 Cooling air duct for lub.-oil cooler 21 Cyclone-type pre-cleaner 22 Eye hook for transport, disappearing max. load 500 kg 23 Access to fuel feed pump 24 Starter motor 25 Fuel feed line 26 Fuel return line 27 Belt pulley with 1/2“ internal square for cranking engine Engine illustrations

Encapsulated design 1 Lub.-oil filling and dipstick 2 Speed control lever 4 Oil drain plug 5 Lub.-oil filter 6 Battery + terminal 7 Battery - terminal 8 Wiring harness 9 Type plate 10 Fuel feed line 11 Fuel return line 14 Cover for capsule 15 Air intake duct of capsule 16 Outgoing air duct 17 Exhaust silencer (encapsulated) 20 Cover for air duct housing (Access to governor housing of engine) 22 Eye hook for transport, disappearing max. load 500 kg 23 Engine brackets 24 Access to fuel feed pump 25 Engine flange 26 Side panel 27 Cover, service side 28 Cover, outgoing air side Operating and governor side Outgoing air and flywheel side Engine illustrations 1 L / M . . 10.98

2 ... 4 M 40, 2 ... 4 M 41 1 Lub.-oil filling and dipstick 2 Side panel 3 Rain protection cap 4 Cooling fan drive belt 5 Cooling fan with built-in alternator 6 Governor housing 7 Hydraulic belt tensioner 8 Stop device 9 Belt pulley with 1/2“ internal square for cranking engine 10 Oil drain plug 11 Speed control lever 12 Lub.-oil filter 13 Oil drain plug (oil sump) 14 Cooling air duct for lub.-oil cooler 15 Access to fuel feed pump 1 L / M . . 10.98 Flywheel side Engine: 2 ... 4 M 31, 2 ... 4 M 40, 2 ... 4 M 41 1 Cylinder head cover 2 Fuel pressure pipe 3 Cover for air filter(s) 4 Eye hook for transport, max. load 500 kg 5 Injector 6 Fuel return line 7 Fuel feed line 8 Wiring harness duct 9 Flywheel 10 Engine flange 11 Starter motor 12 Type plate 13 Exhaust silencer Engine illustrations

H 3 L 30 1 Fuel line (feed pump - filter) 2 Fuel line (filter - injector pumps) 3 Hose connection (Maintenance indicator for air filter) 4 Primer pump 5 Fuel feed line (Fuel tank - fuel feed pump) 6 Lub.-oil filling and dipstick 7 Speed control lever 8 Solenoid, engine stop 9 V-belt 10 Voltage regulator 11 Oil drain plug, governor side 12 Lub.-oil filter 13 Oil drain plug, 14 Fuel pre-filter 15 Oil pressure switch 16 Fuel feed pump (Bosch) Governor- and exhaust side Engine: H 2 L 30, H 3 L 30 1 Cooling water inlet 2 Rain protection cap 3 Air filter 4 Cylinder head cover 5 Fuel pressure pipe 6 Temperature switch 7 Cooling water outlet 8 Exhaust manifold 9 Starter motor 10 Type plate 11 Centrifugal pump 12 Belt-adjustment link 13 Alternator IMPORTANT ! The standard transport suspension enables safe transportation of the engine including supplementary equipments, and is designed for a maximum load of 500 kg (1100 lbs). It is neither suitable nor approved to lift complete units. Engine illustrations 1 L / M . . 10.98

Type plate data Complete type description e.g. Engine type Engine version 2 L 40 C Customer spec. list No. 1) Customer-specification Output in kW 2) Execution code 2) Adjustment instruction 1) Special adjustm. regarding engine speed, power output etc. Injection pump delivery lift in mm to obtain the required engine output. Governor rod travel for adjusting the correct fuel quantity in 1/100 mm Engine number Type-No. 064 10 81 031814 MOTORENFABRIK HATZ KG D-94099 RUHSTORF GMBH CO + TYP KENNZ. MOTOR / FABRIK NO. ABE /AUSF. MIN NH PV CM MADE IN GERMANY -1 3 Displacement in cm3 3000 / 60 Engine speed e.g. Nominal speed Speed increased under no-load condition max. no-load speed 1) If required 2) in special cases only; e.g. engines acc. to Federal Authority for Automobilism Engine series no.: The serial no. begins with 10 and changes continously (11,12) if any major changes are carried out. Year of production Fabrication-No. (continous) 3000 + 60 = 3060 min-1

4 Hydr. starting charge device or oil servo 5 Crankshaft 6 Main bearings 7 Hydraulic belt tensioner 8 Lubricating oil pump 9 Sump 10 Plug – on engines without oil cooler 11 Threaded rod – on engines with oil cooler 12 Oil suction strainer 13 Balancing shaft(s) 14 Lub. oil filter with bypass valve 15 Oil cooler 16 Oil pressure switch 17 Oil pressure relief valve Lubricating oil circuit 1 L / M . . 10.98 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 10 16 17 Suction line Oil pressure feed to filter on engines without oil cooler Oil pressure feed to filter on engines with oil cooler Oil circuit after oil cooler

2 3 4 Bore / stroke mm 95 / 100 Displacement cm3 1416 2124 2832 Compression ratio 18:1 Firing order, cyl.1:timing end 2-1 1-3-2 1-3-4-2 Direction of rotation anti-clockwise (looking at flywheel) Cooling air requirement at n = 3000 rpm m3/min 25 - 35 - 45 Combustion air requirement at n = 3000 rpm m3/min 2.1 3.2 4.2 Net weight approx. kg L 30 S 223 222 255 271 291 L 30 Z 228 228 262 279 306 L 30 C / K 276 - 331 - 396/386 Lubricating oil pressure at n = 800 rpm min.: 0.9 bar Lubricating oil consumption max.: 1 % of fuel consumption, at full load Starter motor 12 V, 2,7 kW or 24 V, 4,0 kW Alternator 14 V, 50 A or 28 V, 40 A* Battery 12 V, 88 / 143 Ah or 24 V, 55 / 110 Ah Max. continuous inclination with and without with without only with towards oil sump oil sump oil sump Operating side 30° 30° 25° 25° Flywheel side 30° 22° 25° 18° Air outlet/starter side 30° 30° 30° 30° Governor side 30° 25° 25° 15° * At H 2 L 30 and H 3 L 30: 14 V, 33 A or 28 V, 27 A 1 L / M . . 10.98 Technical data L 30

Type 2L31 2L40 3L31 3L40 4L31 4L40 2M31 2M40 3M31 3M40 4M31 4M40 Operating cycle 4-stroke Combustion system Direct injection Number of cylinders 2 3 4 Bore / stroke mm 102/90 102/105 102/90 102/105 102/90 102/105 Displacemen cm3 1470 1716 2205 2574 2940 3432 Compression ratio 18:1 Firing order, cyl.1: timing end 2-1 1-3-2 1-3-4-2 Direction of rotation anti-clockwise (looking at flywheel) Kühlluftbedarf bei n = 3000 min-1 m3/min 25 29 35 39 46 49 Combustion air requirement at n = 3000 rpm m3/min 2.1 2.6 3.2 3.9 4.2 5.2 Net weight approx. kg L 31 S, L 40 S, M 40 223 255 291 L 31 Z, L 40 Z, M 40 Z 228 262 306 L 31 C / K, L 40 C / K 276 331 396/386 Lubricating oil pressure at n = 800 rpm min.: 0,9 bar Lubricating oil consumption max.: 1 % of fuel consumption, at full load Starter motor 12 V, 2,7 kW or 24 V, 4,0 kW Alternator 14 V, 50 A or 28 V, 40 A Battery 12 V, 88 / 143 Ah or 24 V, 55 / 110 Ah Max. continuous inclination with and without with without only with towards oil sump oil sump oil sump Operating side 30° 30° 25° 25° Flywheel side 30° 22° 25° 18° Air outlet/starter side 30° 30° 30° 30° Governor side 30° 25° 25° 15° Technical data L 31, M 31, L 40, M 40

Type 2L41 3L41 4L41 2M41 3M41 4M41 Operating cycle 4-stroke Combustion Direct injection Number of cylinders 2 3 4 Bore / stroke mm 102/105 102/105 102/105 Displacement cm3 1716 2574 3432 Compression ratio 18,7:1 Firing order, cyl.1:timing end 2-1 1-3-2 1-3-4-2 Direction of rotation anti-clockwise (looking at flywheel) Cooling air requirement at n = 3000 rpm m3/min 29 39 49 Combustion air requirement at n = 3000 rpm m3/min 1,9 2,9 3,9 Net weight approx. kg M 41 S 223 255 291 M 41 Z 228 262 306 L 41 C / K 276 331 396/386 Lubricating oil pressure at n = 800 rpm min.: 0,9 bar Lubricating oil consumption max.: 0,2 % of fuel consumption, at full load Starter motor 12 V, 2.7 kW or 24 V, 4.0 kW Alternator 14 V, 50 A or 28 V, 40 A Battery 12 V, 88 / 143 Ah or 24 V, 55 / 110 Ah Max. continuous inclination with and without with without only with towards oil sump oil sump oil sump Operating side 30° 30° 25° 25° Flywheel side 30° 22° 25° 18° Air outlet/starter side 30° 30° 30° 30° Governor side 30° 25° 25° 15° Technical data L 41, M 41

Sealants and adhesives: Code letters in the text and drawings refer to the products stated below. The same details appear in our spare part lists. A = 502 230 01 Loctite Activator 500 ml B = 502 231 00 Loctite 573 50 ml C = 502 232 00 Loctite 601 50 ml D = 502 233 00 Loctite 221 50 ml E = 502 234 00 Loctite 648 10 ml F = 502 238 00 Technicoll 8058 750 g + 502 239 00 Technicoll 8367 750 g G = 502 565 01 Loctite IS 407 20 g H = 502 825 01 Silicon 30 ml J = 502 830 02 High-temp. paste 1000 g K = 503 426 00 High-temp. paste 100 g L = 502 566 00 Silicon 100 g 1 L / M . . 10.98

Special tools and workshop equipment Series L / M engines No. Ident-Nr. Code Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 669 350 00 612 110 00 668 383 00 626 753 91 630 094 00 629 223 01 625 739 00 612 092 00 665 418 00 665 030 91 612 087 00 634 142 00 620 926 01 624 838 91 625 383 02 612 090 01 626 383 00 624 845 01 633 178 00 631 191 00 631 203 00 632 913 00 03.1.1 03.1.2 01.1.2 03.1.1 03.1.2 03.1.2 03.2.1 03.1.2 05.2.1 05.1.1 05.1.2 03.1.2 03.1.1 03.1.2 03.1.2 03.1.2 03.1.2 03.2.2 06.2.1 06.1.2 06.1.2 05.1.1 Pressing-in drift ∅9 mm for valve guides Reamer 9 H 6 for valve guide Clamp for fuel line Impact extractor with accessories Test nozzle 400 bar Valve lifting tool Pressing-in drift for valve stem seal 6 mm intl. hex. insert with centering pin Driver sleeve for camshaft bearings Overflow device for injection pump Dial gauge – 1/100 mm Honing tool Oil pressure gauge 0 -6 6 bar with flexible tube Rev. meter for fuel pressure pipe Digital multimeter Piston ring pliers Piston ring clamping tool ∅70 - 100 mm Crimping pliers up to 6 mm2 Relay test box Puller for belt tensioner bushings Installation drift for belt tensioner bushings High-pressure pump cpl.

1 L / M . . 10.98 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Injection - pump timing set A B E C D Relais-Funktions- und Testbox 15 86 87 87a 50 – +

Series L / M engines Explanation of classification: Example: 03. 1. 2 Manufacturer: 1 . . . Only available from HATZ 2 . . . Same item (or equivalent in function) available commercialy Necessity: 1 . . . Absolutely essential 2 . . . Useful or convenient Type of repair: 01. . . Maintenance 02. . . Emergency repair 03. . . Repair in upper and external areas 05. . . Repair in area of driving gear mechanism 5Q. . . General overhaul (including all the necessary tests) 06. . . Component repairs 1 L / M . . 10.98 No. Ident-Nr. Code Item 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 624 340 01 624 346 01 624 347 00 624 348 01 624 349 00 624 350 00 606 000 00 618 140 01 618 418 00 610 390 00 620 300 00 624 393 00 621 056 00 626 211 00 604 628 00 620 307 01 620 638 01 619 746 00 630 439 00 619 852 02 619 854 02 619 855 02 624 863 02 624 864 01 629 055 00 05.1.1 05.1.1 05.1.1 05.1.1 05.1.1 05.1.1 05.1.1 03.1.1 03.1.1 03.1.1 03.1.1 05.1.1 03.1.1 03.1.1 03.1.1 01.1.2 02.1.1 05.1.1 05.2.1 5Q.1.1 5Q.1.1 5Q.1.1 03.2.1 03.2.1 02.1.2 Marking device for radial position of injection pump Gauge for measuring governor rod travel Gauge for adjusting start of fuel injection Calibrating device for tool - 25 - Locating pin for governor rod Fuel injection volume adjusting tool Wrench for starting charge adjustment (mechanical system only) Multipurpose puller in connection with tool - 31 - Forcing-off screw for tool - 30 - Forcing-off screw for centrifugal clutch Forcing-off screw for centrifugal belt pulley Assembly sleeve M 10 x 1 guide pin for conrod M 11 x 1 guide pin for conrod Test pressure gauge for fuel injection system Strap wrench Locking device for tensioning roller Holder for injection timer assembly Gauge for oil spray nozzles Air guide plate for 2 L / M Air guide plate for 3 L / M Air guide plate for 4 L / M Elevating table, mobile Adapter elements for - 45 - Disassembly tools for cable plug

1 L / M . . 10.98 23 24 25 26 27 28 29 30 31 32 / 33 34 35 / 36 37 38 39 40 44 47 42 43 44 46 45

General: – When installing the fuel delivery pump, make sure that the delivery and suction lines are connected correctly. Dismantling: – Disconnect fuel feed line with clamp - 3 -. – Separate the fuel lines from the delivery pump. – Unscrew and remove nuts with spring washers, and take off fuel delivery pump with O-ring. – Dismantle fuel delivery pump 1 in the numerical order of parts illustrated (Fig. 182). Note: Since September 1992 fuel strainer 12 has been replaced by O-ring 5. Because of this, an input-side fuel filter must always be used. This input-side filter is supplied as a spare part with the fuel delivery pump and also with the repair kit for the fuel delivery pump. Assembling: Assemble by following the instructions in the reverse order as appropriate. 2 L / M . . 09.96 182 A 01.00 Fuel A 01.40 Fuel delivery pump 2 3 4 5 6 7 8 9 10 11 1 12

and air outlet duct; see M 35.00. Detaching: – Take out hex bolts (184/1) and detach the connecting stub pipe with exhaust pipe (184/2). On more recent versions, the exhaust pipe is secured with a clip. – Take out the machine screws (184/3) and remove the connecting cover (184/4). – Unscrew and remove the hex bolts (185/1). – Remove the machine screws (186/1) and bolts (186/2). 2 L / M . . 09.96 184 185 186 A 03.00 Exhausts A 03.12 Removing and installing the silencer (muffler) enclosure(L 30, L 31, L 40, C/K) L3 / 228 1 3 4 2 L3 / 229 1 L3 / 230 1 2

(muffler); see Fig. 187. Note: In some cases a spacing plate is installed between the silencer enclosure and the air duct housing. – On the 2 - 3 L 40 from date of manufac- ture 5.85 on, 4 L 40 from 1.86 on and L 31, the connecting stub pipe (189/1), sealing washer (189/2) and plate (189/3) are deleted. Five sealing washers are installed between the silencer and the exhaust manifold. – Pull the upper and lower sections of the enclosure apart and lift out the silencer; see Fig. 188. Check the parts: – Examine the enclosure sections and the silencer for fractured welds or tapped holes which are unfit for further use. Installing: – Install by following the removal instruc- tions in the reverse order as appropriate. The silencer must be installed without trapped stresses (a two-piece holder for the silencer has been installed since March 1989). Note: Before installing the connecting stub pipe (189/1), check free movement of the seal- ing washer (189/2). Place the sealing washer in the connect- ing stub pipe and install the plate (189/3). It should be possible to move the sealing washer radially. Next, place the sealing washer on the silencer. Radial play must not exceed 0.1 mm. If necessary, renew the sealing washer. 2 L / M . . 09.96 187 188 189 L3 / 231 L3 / 232 L3 / 233 1 2 3

Standard crank handle: This handle can be replaced at any time by one with kick-back damping if this becomes necessary or is required by regulations. Attention ! There is a risk of injury if the shaft of the crank handle or its tubular handgrip are worn. Preparations: – Demontage: – Inspection / repair: – Visual inspection. – Inspect shaft 1 and tubular handgrip 2 for wear or breakage. Note: If the shaft of the crank handle is worn, always renew the complete handle. The tubular handgrip can be renewed separately if necessary. 2 L / M . . 09.96 191 A 04.00 Start mechanical A 04.10 Crank handle 2 1

Handle with kick-back damping: The version for M .. engines is marked A on its housing, and takes the place of the standard crank handle if required. Attention ! There is a risk of injury if the shaft of the crank handle or its tubular handgrip are worn. Preparations: – Demontage: – Remove parts in the order 1 ... 3 as illustrated. – Remove machine screws 4. – Take off cover 5 with great care, so that leaf spring 11 cannot escape. Risk of injury! – Remove parts in the order 6 ... 10 as illustrated. – Hold torsion spring 13 in position in order to maintain its tension. – Pull leaf spring 11 away from its locking pin and out of the hook eye on torsion spring 13. – Relieve torsion spring tension with a screwdriver blade. Caution - risk of injury! – Take off parts 12 and 13. Housing 14 remains in position with the other parts. 2 L / M . . 09.96 192 A 04.00 Start mechanical A 04.10 Crank handle 4 7 8 15 14 13 12 11 10 9 6 5 16 15 3 A

– Visual inspection: – Renew the complete starting handle if there is any damage in the area of cover 5 and/or housing 14. – If necessary, renew pivot bushings 15 and shaft sealing ring 16. – Examine tubular handgrip 7 for wear and/or other damage, particularly in the splined area. – Install end plug 8, avoiding damage to the splines. The end plug must installed to prevent dirt and water from entering. – Check condition of bushing and leaf spring at lever 9. – Check condition of leaf spring 11 and torsion spring 13. Renew in case of doubt. – Check shaft 3 for wear and/or other forms of damage. – Renew O-rings and small parts. 2 L / M . . 09.96 Assembling: – Install parts 13 and 12. Use thread sealant D. – Make sure that the torsion spring is not trapped; insert its longer end into the groove on the corresponding locating pin. – Preload torsion spring 13 against the normal spring pressure until the hook eye of the spring engages behind the eye of the through-hole. Caution - risk of injury! – Hold torsion spring 13 in position to pre- vent spring pressure from being lost. – Push leaf spring 11 into the hook eye on torsion spring 13 and place on locking pin.The rolled end of the leaf spring must face toward the center of the housing. – Attach lever 9. – Push on tubular handgrip 7/8. Check splines, lever and leaf springs for free movement. – Apply app. 50 grams of lubricant K to the inside of housing 14 and over all mechanical parts. – Place a new gasket 6 on the housing. – Carefully place cover 6 over tubular handle 7. – Insert machine screws 4 and tighten them evenly in a crosswise pattern. – Install shaft 3 in the order 3 ...1 as illustrated. – Check operation of the complete crank handle.

following positions; Fig. 93: 0 = Operating position, with engine running 1 = Permanent decompression, automatic device switched off 2 = Automatic decompressor switched on, engine compression is built up auto- matically after about 8 turns of the handle. Detaching: – Unscrew cap nut (94/4) with sealing ring (94/5). – Take off cover (94/20) with gasket (94/37). On two-cylinder engines, shafts (94/14) and (94/36) are connected together by coupling sleeve (94/27) and 2 locking collets (94/23). Camwheel (94/22) is then used at the second cylinder (flywheel side) instead of the gearwheel. Dismantling the automatic decompres- sor: – Unscrew and remove screw plug (94/1). – Take out sealing ring (94/2), spring (94/6), cap (94/7) and lifting pin with shims and pressure pin (94/8, 9, 10). – Unscrew threaded rod (94/19) and remove spring (94/18) and pressure pin (94/17). – Using a suitable split-pin driver, drive locking collet (94/16) about 3 mm into gearwheel (94/21). – Turn the gearwheel through 180° and pull the locking collet out with pliers. – Take out shaft (94/14) and gearwheel. 2 L / M . . 09.96 93 94 A 04.00 Start mechanical A 04.20 Automatic decompressor (M 31, M 40, M 41) L3 / 1 1 2 0 kompr. dekompr. dekompr.autom. L3 / 42

age caused by moving the decompres- sion lever in the wrong direction or operating the automatic decompressor when the engine is already running. – Use new sealing rings. Install by following the dismantling instruc- tions in the reverse order as appropriate. Note: – With the automatic decompressor in position „0“, note the correct position of the gearwheel (Fig. 95). – Check that the lifting pin can move freely. – When installing threaded rod (94/19), make sure that pressure pin (94/17) engaged in the locating slot on shaft (94/14). Adjusting the automatic decompressor: Adjustment is needed if: a) the decompression effect is no longer sufficient. b) the engine does not reach its full com- pression ratio (hissing noise when engine is turned over and the decom- pressor is not engaged). c) cylinder head repairs are carried out. Check dimension „B“: – Use a suitable measuring tool to check dimension „B“; Fig. 95. Note: For this check, the rocker should rest lightly on the valve stem but without open- ing the valve (turn the engine over until the tappet is resting on the base circle of the cam). 2 L / M . . 09.96 95 L3 / 43 max. 46.1 mm min. 45.5 mm B A b c

this dimension as follows: – Take off the exhaust rocket, grind down the pressure pin at the riveted side and drive it out. – Install the rocker temporarily, insert the new pressure pin (95/b) and place shims (95/c) under it to the required thickness, until the correct dimension (95/B) is reached. Note that when it is riveted into position, the pressure pin is about 0.1 mm lower. – Rivet the pressure pin into position, pressing it firmly into the bore. The pressure pin should project by at least 1 mm at the riveting point, to ensure firm seating. If it does not project sufficiently, grind the rocker away slight- ly at the appropriate point. Install the rocker finally, noting the endplay; adjust valve clearance and check dimension (95/B) again. Checking dimension „A“: – Using a depth gauge, determine dimen- sion „A“ (Fig. 95); work out the number of shim washers (94/9) needed according to the table, and secure them with the pressure pin (94/10) to the actuating pin (94/8). – Check operation of the automatic decompressor. When decompression is active, it must be possible to turn the engine over with- out compression resistance, but the exhaust valve must never strike the piston. 2 L / M . . 09.96 Dimension „A“ in mm Number of shim washers (Fig.94/9) 14,0 - 14,5 14,5 - 15,0 15,0 - 15,5 15,5 - 16,0 16,0 - 16,5 16,5 - 17,0 17,0 - 17,5 6 5 4 3 2 1 0

see A 03.00. – Remove the fan; see M 13.0 Detaching the recoil starter: (Fig. 190) – Take out machine screws 13 incl. spring washer 5 and screws 12 with bushings 8 and washers 7, and remove them with bearing bracket 11. – Detach the hydraulic shutdown device; see M 20.00. – Remove the timing case cover; see M 11.00. – Take out machine screws 6 with spring washers 5. – Take off starting sleeve 4. Checking parts: – Check the starting sleeve and bearing bracket for damage. – Check shaft sealing ring 3 for damage and renew if necessary. Assemble in reverse order as described here. 2 L / M . . 09.96 190 A 04.00 Start mechanical A 04.70 Recoil starter L3 / 44

side panel; see M 35.00. – On S/Z and M.., take off side panel and cooling air duct for lubricating oil cooler. Detaching and dismantling: – Pull off fuel lines (113/1 and 2). Take out start release device retaining screws and remove the device. – Take off spring (114/9), flexible gaiter (8) and nut (6); take off cylinder (114/2) and remove lock washer (114/5), lever (4) and washer (7).. Checking parts: – Place the cylinder (114/2) in a tank con- taining diesel oil. Apply an air pressure of max. 1.5 bar to the hose line (114/1). If air bubbles emerge from the cylinder, it must be renewed. – Check flexible gaiter for damage and renew if necessary. Re-assembling the start release device: Follow the dismantling instructions in reverse order as appropriate; refer to Fig. 114. Note: When attaching to the engine monitoring block, make sure that locking collet (114/13) is pressed into the start position by lever (114/4), or else the start release action will not take place; see also Fig. 116/1. Before tightening machine screws (114/14), move bracket (114/3) in the opposite direction (see Fig. 116/2), to ensure that locking collet (114/13) can move as far as possible back to the „Stop“ position. 2 L / M . . 09.96 113 114 115 A 04.00 Start mechanical A 04.80 Start release device (L /M 31/40/41) 1 2 1 5 4 7 6 8 3 13 2 14 9 Stop

as shown in Fig. 113. If the hoses are wrongly connected, the automatic engine protection function is no longer available, i.e. the engine is not shut down automatically if lubricating oil level drops too low. – On older engine versions, hose (113/1) is connected to the fuel delivery pump. This has no effect on the basic function of the device. Operational check with start release device installed: – Turn lever (114/4) clockwise; locking collet (114/13) must move to the „Stop“ position (Fig. 116). Release the lever; the locking collet must move back to the „Start“ position. – Prime the fuel delivery pump with the lever and at the same time check whether the piston in cylinders (114/2) moves the lever (114/4) correctly. Also check the cylinder and hose unions for leaks. When the lever is no longer actuated, spring (114/9) exters pressure on the piston, which should then move back slowly (see Fig. 116). Note: If the fuel tank is located at a higher level than the fuel delivery pump, the difference in height between the fuel level in the tank and the fuel delivery pump must not exceed 2 metres. Failing this, the automatic engine protec- tion device will be put out of action and the engine then cannot be switched-off electrically. 2 L / M . . 09.96 116 Start 1 2

electrical system: – Never interchange the positive and neg- ative terminals at the battery. – Do not disconnect the battery when the engine is running. – Avoid all risk of short-circuiting live cables (for instance, never test whether a cable is live by touching it to earth). – If the charge telltale light bulb blows, replace it immediately. – If any welding is done on the engine or the equipment to which it is fitted, attach the earth (ground) clip of the welding set as close to the weld area as possible, and disconnect the alternator from the electrical circuit at connections „B +“ and „D -“. – When cleaning the engine, avoid spraying water on the alternator or any other components of the electrical system. If this is unavoidable, first disconnect the battery; before it is reconnected, dry all components thoroughly with a compressed air jet. – If a malfunction, for instance low battery charge, charge telltale light on etc, should be detected, always check the tightness of cable connections and correct V-belt tension before making any other operational checks. – For trouble-shooting in the event of a fault, see section 4. – When recharging the battery, disconnect the negative terminal. – Avoid using electrical starting aids because of the risk of voltage peaks (these could damage electronic components). 2 L / M . . 09.96 Checking operation of the alternator with voltage regulator (checking charging current): – With the engine stopped and the starting-switch key at „0“, detach the B + line (leading to the battery) from the alternator and connect a DC ammeter with a scale reading of 0 .. 50 A between alternator terminal B + and the detached cable. Make sure that the loose cable cannot touch any metal parts of the engine. – Connect a DC voltmeter with a scale of 0 . . 30 V to the battery's positive and negative poles. – Start the engine and note the meter readings. Check the voltmeter display. With the alternator in good working order and electrical consumers in circuit, the ammeter should indicate a charging current. Its value depends on the battery's state of charge (if the battery is flat, the charging current is high, if the battery is fully charged, the charging current is low), but also on the consumpition of electrical equipment actually in use and on alternator and therefore engine running speed. If there are no consumers in circuit, a charging current should even be indicated at idle speed. If the alternator voltage is too high, renew the voltage regulator. A 05.00 Start electrical Test values System 12 V 24 V Voltmeter reading 13.0 - 14.5 V 26 - 29 V Charging current at 13.5 V or 27 V Battery voltage- – Engine speed 800 rpm (idle) – Engine speed 1500 rpm approx. 25 A 40-45 A approx. 5 A 25-30 A

cover and the impeller wheel. Unscrew and remove the enclosure side panel; see M 35.00. – Take off the Poly-V belt; see M 20.00. Non-encapsulated engines: – Unscrew and remove the V-belt guard if attached. – Take off the air guide plate. – Take off the Poly-V belt; see M 20.00. Removing: – Detach the earth (ground) lead from the battery. – Disconnect the leads from the alternator and mark them (Fig. 193). – Unscrew the hex nuts and pull the rotor with alternator out forwards. – Unscrew the hex nut holding the rotor and drive the alternator shaft through by striking it with a plastic-faced hammer; see Fig. 123. Checking parts: – Examine the fan and the belt pulley for evidence of damage. – If any grooves have broken away or are damaged, renew the fan with belt pulley. Installing: – Install the rotor and the alternator by following the above removal instructions in the reverse order as appropriate. Note: When connecting the cables to the alterna- tor, make sure they are not accidentally interchanged. 2 L / M . . 09.96 193 (*HATZ-internal cable marking) 194 A 05.00 Start electrical A 05.40 Alternator (air-cooled engines)

When series production of Series L / M engines began, alternators made by SEV- MARCHAL were used. These alternators are no longer available as spare parts, but can be replaced without difficulty by the current VALEO alternator. The MARCHAL voltage regulator is still available. In view of the modified installed position of the voltage regulator on PARIS- RHONE or VALEO alternators (removal and installation in a radial direction to reduce the risk of breaking off the carbon brushes), the fan housing was also modified in the regulator area when the PARIS-RHONE generator was introduced. A cutout in the housing and deletion of the retaining screw which previously passed through at this point ensure that the regulator switch can be renewed with- out having to remove the alternator. When replacing a MARCHAL alternator by a VALEO type, you are recommended to perform the above modification; refer to Fig. 195. The time invested in this will easily be made good by the time saved if the regulator has to be replaced later. When installing a VALEO voltage regulator, make sure that the condenser supplied with it is also installed (connec- tion diagram is enclosed). 2 L / M . . 09.96 195

the enclosure hood and side panel; see M 35.00. – On engines without enclosure, take off the cooling air duct to the oil cooler. Removing block-pattern oil cooler: – Remove the oil line to the servo (only on older version of the engine). – Take out machine screws (196/1) and detach the oil cooler. Removing gilled-tube oil cooler: – Take out machine screws (197/1) with spring washers and detach oil cooler with sealing rings (197/5). – To dismantle the oil cooler: Pull the oil guides (197/2) apart and take out both gilled tubes (197/3) with O-ring seals (197/4). Note: The gilled-tube oil cooler is only used on two-cylinder engines without enclosure and rated for engine speeds up to a certain limit. Checking parts: – Make a visual check for cracks or damage to the sealing faces. – Clean the cooling surfaces. Installing: – Install the oil cooler by following the appropriate removal instructions in the reverse order. Retrofitting engine with oil cooler: – If an engine has an oil cooler retrofitted, the missing threaded rod (198/3) must be inserted and secured with sealant D. Unless this work is performed, the oil cooler will be unable to operate. 2 L / M . . 09.96 196 197 198 A 07.00 Lubricating oil A 07.10 Oil cooler (air-cooled engines) L3 / 189 1 L3 / 10 1 2 5 3 4 2 L3 / 190 3

– Detach the coolant lines from the oil cooler. Removing:: – Take off the oil filter (199/1). – Unscrew and remove the threaded sleeve (199/2). – Take off the oil cooler (199/3) with spac- ing ring (199/4) and O-ring seal (199/5). Checking parts: – Make a visual check for cracks or damage to the sealing faces. Installing: – Install the oil cooler by following the removal instructions in the reverse order as appropriate. Note: – Install the oil cooler side with the sealing ring towards spacing ring (199/4). – Tighten threaded sleeve (199/2) to a torque of 55 Nm. 2 L / M . . 09.96 199 A 07.00 Lubricating oil A 07.11 Oil cooler (water-cooled engines) 5 1 2 3 4

starting aid housing, taking care not to turn the volume limiting eccentric. – Take out machine screws (205/1) and remove solenoid (205/2). – Pull eccentric shaft (205/3) towards the solenoid and unscrew hex nut (205/4) with a 10 mm open-ended wrench. – Pull out the eccentric shaft and remove washer (205/5), lever (205/6), washer (205/7) and spring (205/8). Inspection / repair: – Use a new O-ring seal (205/10). – Check flexible gaiter for damage and renew if necessary. Assembling: – Proceed in the opposite reverse; install end cap (205/9) with sealant C. 2 L / M . . 09.96 205 A 11.00 Automatic devices A 11.10 Engine shutdown solenoid (up to serial numbers 2 L 40.16, 3-4 L 40.15, M 40.12, L 30 and H.L 30) L3 / 199 2 1 10 3 8 7 4 6 5 9

solenoid: The solenoid does not need adjusting unless the adjusting nuts were turned or a new solenoid has been installed. – Press in the solenoid fully against the spring loading. – Insert solenoid adjusting gauge 621 471 00 (206/1) into the hole in the housing; see Fig. 206. – Turn adjusting nut (207/1) until lever (206/2) is touching the adjusting tool. Note: If the adjusting gauge is not available, the shutdown device can be adjusted to the checking distance of 39.3 ± 0.1mm between the inner face of the hole in the cover and the inner edge of the lever; Fig. 207. – After adjusting, secure the adjusting nut with locknut (207/2) and seal it with lacquer. Installing the shutdown device: – Set the speed control to the „Stop“ posi- tion. – Coat both sides of the gasket (208/1) for the housing with sealant H. Apply only a thin coat of the sealant so that the oil passage in the starting fuel supply device is not blocked. – Attach the gasket (note correct position of oil hole) and press the solenoid by hand into the operating position: angle (208/3) must engage to the left of the driver pin on governor rod (208/4). – In this position, attach the housing and reconnect the solenoid. Attention! If the angle is positioned incorrectly when installed (at the right of the driver pin), the engine will overspeed and could destroy itself unless the solenoid is put out of action immediately. When the U-pattern driver pin was introduced, incorrect positioning as described above was ruled out. 2 L / M . . 09.96 206 207 208 L3 / 200 1 2 L3 / 201 1 2 39.3 ì0.1 L3 / 202 1 2 4 3

Adjusting: – Screw in adjusting tool - 28 - and attach measuring device - 24 -. – Pull the speed control lever briefly to „Stop“ and then to the full-load position.This places governor lever 1 against full-load stop 2 of the starting fuel volume control. – Zero the dial gauge. – Screw thermo-element 4 carefully into the bracket, until the dial gauge just begins to move (the sickle-shaped lever is then against the governor rod). – Unscrew adjusting tool - 28 - at the 13 mm hexagon until a clicking sound is clearly heard, to indicate that the gover- nor lever is dropping into the increased- volume starting position. – Slowly turn thermo-element 4 back to a lower setting until the dial gauge indi- cates a movement of 0.2 mm towards increased volume from the zero position previously obtained. – In this position, secure the thermo- element with the locknut. – Detach auxiliary tools and install any engine components not yet in place. Attention: When adjusting, make sure that the thermo-element is at a temperature of at least 20°C. 2 L / M . . 09.96 170 A 11.00 Automatic devices A 11.70 Temperature-controlled starting fuel volume control 3 2 1 4

crankcase. – Attach the connecting housing, insert four M 14 x 1.5 mm hex bolts (200/2) with spring washer (200/3) and tighten to the specified torque. Note: Apply sealant D to the bolt above inspection hole (200/4), since this is a through-hole. On engines without a connecting housing, the equivalent screw plug should also be coated with sealant D before inserting. – Insert and tighten the two lower M 10 hex bolts (200/5) with spring washers (200/6). 2 L / M . . 09.96 200 A 15.00 Housing A 15.20 Connecting housing L3 / 143 1 2 4 3 5 6

– Take off the alternator. Dismantling: (Fig. 201) – Detach the coolant lines at the water pump. – Unscrew hex bolts 1 with spring washers 2 and take off the water pump. – Remove screws 3 with spring washers 4 and take off V-belt pulley 5. – Take out screws 6 with copper washers 7 and remove pump element 8 with seal 9 from housing 10. Checking parts: – Check housing for evidence of damage. Note: If the following damage is detected, renew complete pump element 8: – Damaged pump impeller. – Worn sealing ring in pump element (water leaking from the hole in the pump element). – Bearing worn. Assembling: – Assemble by following the dismantling instructions in the reverse order as appropriate.Install pump element 8 with the water drain hole facing down. 2 L / M . . 09.96 201 A 30.00 Liquid cooling A 30.20 Water pump (H.L 30) 1 2 4 3 5 6 7 8 9 10

upper edge of the radiator is higher than the thermostat). – Detach the coolant line from thermostat cover (202/3). Dismantling: – Take out retaining screws (202/1) with spring washers (2). – Lift off the thermostat cover (202/3). Remove sealing ring (4) and pull out thermostat (5). Checking operation of thermostat insert: Note: The temperatures stamped on the thermostat insert indicate the start of its opening movement and the maximum operating temperature. – Suspend the thermostat insert and a thermometer in the centre of a vessel filled with water; see Fig. 203. – Heat the water while stirring it. – Check that the thermostat insert opens at the temperature stamped on it. – Remove the thermostat insert and check that it closes correctly. – Renew thermostat insert if defective. Assembling: – Clean the sealing faces on the cylinder head, the thermostat cover and the seat of the thermostat insert. – Install the thermostat insert, using a new sealing ring (the arrow stamped on it indicates the direction of flow). – Attach the thermostat cover again and tighten its screws uniformly. 2 L / M . . 09.96 202 203 A 30.00 Liquid cooling A 30.40 Thermostat (H.L 30) 1 2 4 3 5 6

1 2 3 – Preparations: – Remove the crankshaft, see M 02.00. Dismantling: – Unscrew and remove machine screws (1/1) at driver (1/2). Note: On the 3 L, also unscrew and remove the machine screws at the divided driver. – Unscrew and remove the machine screws (2/1) at the plate (2/2) and take off the plate.(On more recent version: secured with stud bolts and nuts) – Unscrew the plug from the thrust bus- hing at the timing end of the engine and drive the shaft out towards the flywheel end; see Fig. 3. – Drive out the thrust bushing (timing end). – Take the balancing weights and driver out of the lower part of the crankcase. Inspection / repair: – Check the shaft at its bearing points for score-marks and correct dimensions; for values, see Section 4. – Check the needle roller bearings of the balancing weights for score-marks. – Check the gearwheel with balancing weight and the crankshaft-end gear- wheel for the balancing weights for signs of damage. – Renew the O-ring seals at the thrust bushings. M 01.00 Crankcase M 01.10 Removing and installing balancing weights - 2L / 3L

until flush with the housing. – Place the gearwheel with balancing weight (flywheel end) and the balancing weight (timing end) in the lower part of the crankcase, insert the driver and screw hand-tight to the balancing weights. Insert the shaft with thrust bus- hing (4/1) from the flywheel end , see Fig. 4, and drive it fully into the timing- end thrust bushing. – Tighten the machine screws for the dri- ver and use a depth gauge to measure endplay at the balancing weights; see Fig. 5. Note: The timing-end thrust bushing (5/1) forms part of the sealing face at the timing case cover, and must therefore be flush with the endface of the crankcase after driving in the shaft. Endplay can be adjusted by moving the flywheel-end thrust bushing axially until the value stated in Section 4 is obtained. – Apply sealant D to the machine screws (6/1) and attach the plate; also coat the screw plug for the timing-end thrust bus- hing with sealant D and screw it in. Turn the balancing weights to ensure free rotation. Note: When installing the oil sump and the crankcase cover, apply sealant D to two M8 hex bolts in each case at the timing and flywheel ends, where a through-hole has been drilled. 3 L / M . . 09.96 4 5 6

– Take off the oil sump. Dismantling: – Unscrew the machine screws (7/1) at the bearing journals (7/2) and pull them out.Using two machine screws, loosen the bearing journals and pull them out.Mark the installed positions of the bearing journals. – Invert the lower part of the crankcase. Note: The joint line is a sealing face, and must not be damaged. Place the crankcase on a wooden grid or frame; see Fig. 8. – Unscrew splash plate (9/1) and take out balancing weights (9/2), then remove splash plate (9/3). 3 L / M . . 09.96 7 8 9 M 01.00 Crankcase M 01.20 Removing and installing balancing weights - 4 L

(10/1) and, if necessary, drive them out with a suitable drift. First drive the end caps out of the crankcase bores (10/2). Inspection / repair: – Check the bearing journals and bus- hings for score-marks and incorrect dimensions; for values, see Section 4. – Check the balancing weight gearwheels and the crankshaft-end gearwheel for the balancing weights for damage. Assembling: – Blow through the oilways thoroughly with compressed air. Note: Before installing the bearing bushings, make sure that the oil hole is in the cor- rect position; see Fig. 11. – Coat the bearing bushings (12/1) with sealant D and drive them into the hou- sing until flush, using a suitable drift; see Fig. 12. – Coat the sealing faces of the end caps (10/2) with sealant C and insert them again. – Renew the end caps. 3 L / M . . 09.96 10 11 12

in the correct positions as shown in Fig. 13. Note: Insert the longer spacing rollers (13/1) at the oil filter flange side. – Insert splash plate as shown in Fig. 14, insert the lower machine screws (14/1) and tighten them. Screw the upper ma- chine screws (14/2) in only hand-tight. – Insert the balancing weight with circle and line markings as shown in Fig. 15, and push in the bearing journal. Note: This balancing weight is driven directly from the crankshaft. 3 L / M . . 09.96 13 14 15

mark (16/1) and push in the bearing journal. Note: When installing this balancing weight (16/1), make sure that the circle mark on it is between the two line marks on balan- ce weight (16/2). In this position, the circle mark on balan- cing weight (16/2) must face the cranks- haft. – Take out the two machine screws at holes (17/1) again. Place spacing rollers (17/2) on the splash plate. Insert splash plate (17/3) and screw in hex bolts (17/4) hand-tight. – Insert machine screws (17/1) and tigh- ten; also tighten hex bolts (17/4). – Turn the lower part of the crankcase back upright again (joint line at the top). – Insert the machine screws at the bea- ring journals and tighten them to the specified torque with a torque wrench; Fig. 18. – Rotate the balancing weights and check for free movement. Note: When attaching the oil sump, apply sea- lant D to two M8 hex bolts in each case at the timing and flywheel ends, since these are inserted in through-holes. Engines with an oil sump attached must not have a ∅40 mm end cap in the lower part of crankcase. 3 L / M . . 09.96 16 17 18

Cleaning the crankcase – Remove all screw plugs from the oil- ways and, after cleaning the crankcase by immersion in a cleaning bath or with high-pressure cleaning equipment, blow it dry with compressed air; flush out all oilways particularly thoroughly and blow through them, so that no particles of dirt or swarf remain. – After this, insert all screw plugs again and check that the aluminium or sheet- metal plugs for the oilways are firmly seated. In case of doubt, renew them; apply sealant E to all plugs before inser- ting. To ensure firm location, secure the aluminium plugs with light punch-marks at the edge of the hole in the housing. Oil spray jets – First check for firm location and accura- te spray direction; if necessary, re-align the spray jet with light hammer-blows or bend it carefully by hand until the cor- rect position is reached. Check this with the gauge - 41 -or work from the dra- wing shown here (Fig. 171). If oil spray jets have broken off or are loo- se, new ones must be inserted. Proceed as follows: – Remove pieces of the old jet from the drillway (with a suitable drift or similar tool); degrease the entire area tho- roughly; insert the new spray jet and drive it in initially app. 6 - 8 mm farther than its final position. Strike the projec- ting end lightly with a hammer to bend it slightly and ensure a firm seating in the bore (Fig. 172). 3 L / M . . 09.96 171 172 M 01.00 Crankcase M 01.30. Cleaning the crankcase, installing the oil spray jets

and move the spray jet to its final posi- tion. Do not dent the jet inlet bore; drive it in until the end of the tube is flush with the oil groove in the bearing seat (Fig. 173). – Check the position of the jet outlet again, and adjust if necessary. – Apply sealant E again where the spray jet passes through opposite the bearing seat; the capillary action of the sealant will ensure that the tube is fully coated and cannot shake loose in its seat. Note: On Series L 41 and M 41 engines, an oil spray jet is also installed for cylinder 1. 3 L / M . . 09.96 173

Preparations: – Take off enclosure parts and air guide plates; see M 35.00. – Take off cylinder heads; see M 07.00. – Detach fan and V-belt pulley from crankshaft; see M 13.00. – Remove piston, conrod and cylinder; see M 05.00 / M 06.00. – Take off flywheel and connecting hou- sing. – Detach the timing case cover; see M 11.00. – Take off the starter motor. Dismantling: – Remove machine screws and spring washers for end cover and pull off the end cover; see Fig. 19. – Unscrew the machine screws(20/1) and pull them out. – Remove machine screws from cranks- haft gearwheel, loosen the gearwheel on the crankshaft with a plastic-faced hammer and pull it off. – Pull out the locking collet (21/1). 3 L / M . . 09.96 19 20 21 M 02.00 Crankshaft

(22/1) at both sides. – The two halves of the crankcase are se- cured together with straight pins (23/1). Drive these back with a hammer and a suitable drift until they are flush with the sealing face. Lift up the upper part of the crankcase vertically: Fig. 23. Note: To simplify the loosening and lifting off of the upper part of the crankcase, insert two M 8 x 65 machine screws (retaining screws of setting-down device) at the timing end and two M 14 x 50 hex bolts (used to secure connecting housing) at the flywheel end in the holes provided. – Lift the crankshaft out of the lower part of the crankcase. – Carefully warm the balancing weight gearwheel on the 2 and 3 L ... with a welding torch and knock it off with an aluminium drift. For the 4 L ... crankshaft, unscrew and remove the flywheel-end counterweight, remove the machine screws for the gearwheel and drive out the straight pin (24/1). 3 L / M . . 09.96 22 23 24

– Check all crankshaft bearing journals for score-marks and incorrect dimen- sions; for measured values, see Section 4. Measure in two planes offset through 90 degrees. – Check the shaft sealing ring contact face for score-marks. If the contact face is worn, a „wear sleeve“ can be pushed over it. When do- ing so, use sealant E. Assembly instruc- tions are included with the spare part. – Renew the shaft sealing ring in the end cover. – Check the bearing shells for damage and visible signs of wear. Installing: – Pull the balancing-weight gearwheel on to the crankshaft.On the 2 and 3 L .. crankshafts, unscrew and remove the flywheel-end counterweight; this will ex- pose the line marking (25/1) on the crankshaft. Heat the gearwheel to app. 125° C and pull it on so that the line marking (25/1) on the crankshaft is aligned with the „O“ marking (25/2) on the gearwheel; see Fig. 25. On the 4 L ... crankshaft, unscrew and re- move the flywheel-end counterweight and manoeuvre the balancing-weight gearw- heel into position as shown in Fig. 26. – Apply sealant C to the straight pin (24/1) and drive it in. – Apply sealant D to the machine screws and tighten them to the specified tor- que. Note: From mid-1994 on, a modified gearwheel and different retaining screws were intro- duced. The new screws are not to be used with the old gearwheel (Fig. 27). On the 2 and 3 L .. engines, do not install the counterweights again until the crank- shaft has been placed back in the lower part of the crankcase. 3 L / M . . 09.96 25 26 27 5,5 6,5 alt neu

crankshaft so that the lubricating groo- ves face the thrust face on the cranks- haft. Insert the bearing half-shells (28/2) into the lower part of the crankcase, and apply oil to them. – Place the crankshaft in the lower part of the crankshaft and make sure that the gearwheels mesh together as indicated by the marks. For 2 / 3 L ... see Fig. 29. – For 4 L ... see Fig. 30. 3 L / M . . 09.96 28 29 30

main oilway into the lower part of the crankcase. Apply a thin, uniform coat of sealant B to all areas of the joint line on the lower part of the crankcase, and al- so on the intermediate webs of the crankcase; see Fig. 31. – Insert the bearing shells into the upper part of the crankcase and coat them with oil. – Position the thrust washers so that the groove (32/1) faces upwards in each case. Lift upper part of crankcase and place it very carefully. Note: When installing, make sure that the two centering pins (32/2) in the upper part of the crankcase are inserted into the grooves (32/1) of the thrust washers; see Fig. 32. – Drive in the straight pins (23/1) again to locate the two halves of the crankcase. – Insert the machine screws and tighten them to the specified torque in the order shown in Fig. 33. 3 L / M . . 09.96 31 32 33

gauge, Fig. 34, and compare it with the desired value stated in Section 4. – Drive the locking collet to secure the gearwheel (21/1) into the end of the crankshaft. – Turn the camshafts until the two marks (35/1) are aligned and the mark for the crankshaft gearwheel faces downwards. – Engage the crankshaft gearwheel, no- ting the position of the mark, and tigh- ten it to the specified torque. – Place the gasket (36/1) on the locking collets. – Insert a new shaft sealing ring and grease its sealing lip. Install the end cover, coat the machine screws with sealant D and tighten them to the speci- fied torque. 3 L / M . . 09.96 34 35 36

Preparations: – Take off the upper part of the crankca- se; see M 02.00. Dismantling: – Remove the circlip (37/1) at the cover, pull the cover (37/2) out with water- pump pliers and remove the shim washers. – Stand up the upper part of the crankca- se, take the circlip (38/1) out of the sa- fety groove and press the valve tappet (38/2) off the camshaft. – Using a ∅47 mm driving-out sleeve, drive the camshaft out towards the timing end (see Fig. 39) and pull out the valve tappets. 3 L / M . . 09.96 37 38 39 M 04.00 Camshaft M 04.10 Camshaft, valve gear

and pull off the ball bearing with a two- arm puller; see Fig. 40. – If the gearwheel or camshaft is rene- wed, use puller - 30 - with forcing-off screw - 31 - to pull the gearwheel off the camshaft; see Fig. 41. Inspection / repair: – Inspect the camshaft bearing points and the bearing bores in the crankcase for score-marks and incorrect dimensions; for values, see Section 4. – Check the camshaft gearwheel for score-marks. – Check the camshaft ball bearings for wear. – Check the tappets for score-marks. –Check the bores in the crankcase for the tappets for score-marks and incorrect dimensions; for values, see Section 4. Assembling: – Heat the camshaft gearwheel to approx. 150 - 200°C on a hotplate, and press it on. – Place the circlip (42/1) in position and pull on the ball bearing with impact sleeve - 9 -; see Fig. 42. 3 L / M . . 09.96 40 41 42

sure that there is no endplay between the ball bearing and the circlip (43/1). If necessary, insert shim washers (43/2). – Install the camshaft, noting the correct positions of the marks, and insert circlip (44/1). – Drive the camshaft towards the timing end of the engine until the ball bearing is in contact with the circlip (44/1). – Insert shim washers (43/3), push in co- ver with O-ring seal (43/4) and attach circlip (43/5). Note: – Check camshaft endplay; for values, see Section 4.If necessary, insert shim washers (43/3). – A special camshaft has been introduced to operate the valves on the following engines.It can be identified by an „H“ cast into the camshaft. 2 M 31 H from No. 841087 000008 3 M 31 H from No. 851087 000004 4 M 31 H from No. 861087 000004 2 M 40 H from No. 781487 001631 3 M 40 H from No. 791487 000952 4 M 40 H from No. 801487 000873 3 L / M . . 09.96 43 44

Preparations: – Remove the injection pump; see M 14.00. – Remove the engine speed control; see M 32.00. – Remove the starting-mixture charging device; see M 12.00. – Remove the fuel delivery pump. Dismantling: – See M 04.10. Detaching the intermediate gearwheel: Note: The intermediate gearwheel can only be pulled off after removing the injection pump camshaft. – Take off the circlip (45/1) and unscrew the splash plate (45/2) – Pull off the gearwheel with the puller - 30 - and the forcing-off screw - 31 - : see Fig. 46. Note: The two ball bearings in the intermediate gearwheel are separated by a circlip. Inspection / repair: – Check the camshaft bearing points and the bearing points in the crankcase for score-marks and incorrect dimensions; for values, see Section 4. – Check the ball bearings for the cams- haft and the intermediate gearwheel for wear. 3 L / M . . 09.96 45 46 M 04.00 Camshaft M 04.20 Camshaft for injection pump

Note: The intermediate gear wheel must be in- stalled before the camshaft for the injec- tion pump is installed. – Press the ball bearing into the interme- diate gearwheel and pull the gearwheel on using impact sleeve - 9 - , noting the positions of the markings; see Fig. 47. – Place the circlip on the shaft. Note: Before pulling on, place the intermediate gearwheel uniformly on the shaft, to pre- vent the shaft from being pushed into the crankcase. Installing the camshaft: – See „Installing camshaft for valve gear“ (M 04.10). Note: The camshaft for L 40/M 40 is marked „L 40“ next to the delivery pump drive cam. 3 L / M . . 09.96 47

Preparations: – Removing camshaft for injection pump; see M 04.20. Dismantling the governor: (up to engine serial number: 2 L 40.16, 3-4 L 40.15,.M 40.12 and .L 30 and H.L 30) – Remove circlip (48/1) and pull out governor spring (48/2). – Detach spring from governor (48/3) and push out pin (48/4) with roller sleeves (48/5). – Pull out spring sleeve (48/6) with pull rod (48/7). – Unscrew spring bridge (48/8) and take off holder for governor weights (48/9). Dismantling governor: (from engine serial number: 2 L 40.17, 3-4 L 40.16, .M 40.13, and all L 31 and M 31 engines) – Remove circlip (48a/51) and pull out spacing ring (48a/50), spring plate (48a/49) and governor spring (48a/45). – Remove the spring at the governor col- lar (48a/11) and push out pin (48a/38) with roller sleeves (48a/37). – Pull out the pull rod (48a/36), unscrew the nuts (48a/44) and take off the spring plate at the governor (48a/43), the loca- ting washer (48a/42) and needle roller race (48a/41), the shim washer (48a/40) and the thrust washer (48a/39). – Unscrew the spring bridge (48a/32) and take off the holder for the governor weights (48a/26). Inspection / repair: – Check al parts for damage and signs of wear. 3 L / M . . 09.96 48 48a M 04.00 Camshaft M 04.30 Governor and injection timer

timer: – Using puller - 30 - with pressing-off screw - 31 -, pull the injection timer off the camshaft; see Fig. 49. – Clamp the holder for injection timer as- sembly - 40 - into the vise and place the hole in the injection timer's support disc on the special tool; see Fig. 50. – Turn the gearwheel counter-clockwise by hand against the spring loading, and lift it carefully off the support disc. – Take off the centrifugal weights (51/1), retaining blocks (51/2) and pins (51/3) with coil springs (51/4). – Unscrew and remove the cam tracks (51/5). Inspection / repair: – Examine the support disc and gear- wheel in the centrifugal weight area for score-marks. – Inspect the coil springs and their retai- ning blocks for damage. – Check the centrifugal weights for score- marks. 3 L / M . . 09.96 49 50 51

– Assemble the injection timer by follo- wing the dismantling instructions in the reverse order. Note: The gearwheel and support disc were modified at the beginning of 1992. Parts from the old and new versions can- not be combined. If necessary, renew the complete injection timer. After placing the gearwheel on the sup- port disc, check that the slots in the gearwheel and support disc are aligned as shown in Fig. 52. – Turn the injection timer clockwise and allow it to move back to check its free- dom of movement; see Fig. 53. – Coat the hole in the support disc with sealant C and press the camshaft (with shaft key) into the injection timer until the gearwheel has 0.05 mm of endplay. Note: Check endplay with a feeler gauge as shown in Fig. 54. 3 L / M . . 09.96 52 53 54

– Assemble the governor by working the reverse order of dismantling; refer to Figs. 48 and 48a. Note: When assembling the governor make quite sure that all moving parts are able to move freely. On L/M 31/40 engines there must be a clearance of 0.5 mm between spring plate (48a/43) and nut (48a/44). On L/M 41 engines the spring plate (48a/43) must be held firmly when nut (48a/44) is tightened. – Install the spring for the governor (55/1) so that the endface of the tapered sec- tion points in the direction of rotation. Renewing governor spring: (without detaching the timing case cover) Preparations: – Remove the engine shutdown device; see M 20.00. – On the H.L30 take off the cover; see M 11.00. Dismantling: – Remove circlip (56/1) and spring plate (56/2). – Take out governor spring (56/3) and check it for cracks or breakage. Assembling: – Choose the correct new governor spring as stated in Section 4, according to the engine's intended use and speed range. – Install the governor spring or engine shutdown device by working in the reverse order for removal. 3 L / M . . 09.96 55 56

Preparations: – Take off the cylinder head; see M 07.00. – Remove the cylinder and piston; see M 06.00. Dismantling: – Unscrew and remove the big-end bolts (62/1) and lift out the conrod and big end cap with the aid of guide pin - 35 - or - 36 -. Inspection / repair: – Check the conrod bushing, big end bea- ring and crankpin for score-marks and incorrect dimensions; for values, see Section 4. Assembling: – Press the bushing into the conrod. Note: When pressing in the conrod bushing, make sure that the oil holes are aligned and that the bushing projects by an equal amount on each side. – Insert the big end bearing half-shells into the conrod, making sure that the locating nuts are in the grooves provi- ded; see Fig. 63. – Install the big end cap, using guide pin - 35 - or - 36 -; see Fig. 64. – Attach the upper part of the conrod, in- sert the big end bolts and tighten them to the specified torque. Note: The groove (63/1) in the big end cap must be on the side nearest to the injection pump. The groove (63/2) in the main conrod must be on the valve tappet side. 3 L / M . . 09.96 62 63 64 M 05.00 Conrod

M 06.00 Piston and cylinder M 06.10 Air-cooled engines - 12 - 16 - 17 - Preparations: – Detach the cylinder head; see M 07.00. Dismantling: – Mark the relative position of the cylinder and piston and pull off the cylinder. – Take out the piston pin circlip; see Fig. 65. – Press the piston pin out by hand and lift off the piston. Inspection / repair: – Check the cylinder wall for seizure marks or score-marks. – Check that the dimensions of the cylinder are correct; for values, see Section 4. – Check the piston for seizure marks or ring web fractures. – Check piston ring end gaps; for values, see Section 4. Checking piston ring end gaps: –Pull the piston rings off the piston. – Place each piston ring in its cylinder bore and move it to the TDC position of the piston. – Clean the piston crown and use it to po- sition the piston ring at a right-angle to the cylinder axis. – Use feeler gauges to measure the piston ring end gap (where the ends of the piston ring come together). – For limit values, see Section 4. 65 Checking cylinder wear and suitability for further use: – Repeat the piston ring measuring pro- cedure with a new piston ring. – Compare the measurements obtained in this way with the maximum wear limits; if these are exceeded, the cylinder should not be re-used but an oversize cylinder should be installed instead. – If the measured values are within the limits, the cylinder can be used again, with new piston rings. In this case, the cylinder wall must be roughened very slightly with a honing tool, since the honed finish will have been lar- gely worn after a lengthy period of opera- tion. If the cylinder were to be used again without re-honing (whether the existing piston rings or new ones were fitted), ex- cessive oil consumption would occur and would not drop to the normal level after a time, since the piston rings would not be able to match themselves to the cylinder wall.

cylinder, it must also be axially moved back and forth. Recommended speed of rotation approx. 350 rpm. – Depending on the speed, the tool should perform about 20 - 30 strokes a minute. This stroke rate will produce a cross-cut pattern at approximately 45°. – Continue honing only until this crosscut pattern can be clearly seen. It is nor- mally obtained after a honing time of approx. 20 - 45 seconds per cylinder. – After honing, clean the cylinder with warm or hot water and a cold cleanser, using a brush, then oil the cylinder wall. Attention ! Do not hone for too long period, and do not dry-hone. Use honing oil or a mixture of oil and fuel (1:1). If possible, keep below the speed stated above. Wear protective goggles! Assembling: To install the piston, follow the dismantling instructions in the reverse order. Note: The recess in the piston crown must be located towards the injection pump; see Fig. 66. – The piston ring gaps must be offset by 120° in each case; oil the piston rings in their grooves. – Attach clamping tool - 17 - and carefully install the cylinder; see Fig. 67. 3 L / M . . 09.96 66 67

Preparations: – Take off the cylinder head; see M 07.00. – Take off the alternator and water pump. Dismantling: – Carefully pull the cylinder off. – Take out the piston pin circlip; see Fig. 68. – Press the piston pin out by hand and lift off the piston. Inspection / repair: – Examine the cylinder for seizure marks or score-marks on the cylinder wall. – Check cylinder dimensions and state of wear; see Section 4. – Inspect piston for seizure marks and ring web breakage. – Check piston ring end gap; see Section 4. – Check piston ring end gap, cylinder wear and suitability for further use; see Section 4. 3 L / M . . 09.96 68 M 06.00 Piston and cylinder M 06.20 Water-cooled engines (H.L 30)

procedure in the reverse order as appro- priate. Note: The recess in the piston crown must be located towards the injection pump; see Fig. 69. – The piston ring gaps must be offset by 120° in each case; oil the rings well in their grooves. For each cylinder bore a figure is stam- ped on the crankcase and another figu- re on the cylinder. The two figures, if ad- ded together, represent the thickness of the shim plates to be inserted at the ba- se of that cylinder; see Fig. 70. Example: Figure on crankcase 15 Figure on cylinder 20 Shim plate thickness needed 35 = 0.35 mm These shim plates compensate for cylin- der and crankcase manufacturing toleran- ces; in addition the gap is reduced to within a tolerance range of 1.0 - 1.5 mm. – Attach shim plates 70/1 to the cylinder with a small amount of grease. – Oil the cylinder bore well. Note: If spare parts are obtained, the manufac- turer attaches the shim plates to the crankcase or cylinder. They are not inclu- ded in the set of gaskets. To order them separately, please quote the following part numbers: 036 330 00 0.10 mm 036 388 00 0.15 mm 036 329 00 0.20 mm 3 L / M . . 09.96 69 70

on H 3 L 30: – Set pistons „1“ and „3“ to approximately the same height and attach piston ring clamping tools - 17 -; attach piston ring clamping strap 622 469 00 to the centre piston; see Fig. 71. – With the help of a second person, care- fully place the cylinder assembly in position and insert auxiliary pins 621 646 00 into the recesses on pistons „1“ and „3“; see Fig. 72. – Lower the cylinder assembly and at the same time move the auxiliary pins back and forth until the pistons enter the cy- linders. – Take off the piston ring clamping tools and move the centre piston back and forth during the lowering movement until it enters its cylinder. – The ring clamping strap is pushed into the cylinder, and can then be pulled out of the rectangular side opening in the crankcase with the aid of a strong piece of wire. Installing the cylinder assembly on the H 2 L 30: – Set both pistons to approximately the same height and attach the piston ring clamping tools. – Further installation work is as described for the H 3 L 30, but without the work relating to the centre cylinder. 3 L / M . . 09.96 71 72

– Take off the exhaust-side enclosure and the muffler (silencer); see A 03.00. – Unscrew and remove the air outlet shaft, side panel and cross-member; see M 35.00. – Unscrew and remove the cover plate and take out the screws for the base plate; see M 35.00. – Take off the air cleaner. – Remove the injector; see M 14.00. Dismantling: – Take off the cylinder-head (rocker) cover. – Unscrew the shouldered nuts (73/1) and bolts (73/2). – Pull off the centering flanges (73/3). – Detach the support plate mounts. – Press the air guide housing and suction shaft apart. – Lift off the support plate; see Fig. 74. – Detach the exhaust manifold and air in- take pipe. Note: To simplify dismantling of the air intake pi- pe, it is best to unscrew and remove the air cleaner (74/1). – Lift off the cylinder head and remove the pushrod protective tubes. Checking the cylinder head: – Inspect for cracked webs or worn valve tapers. – Check the radius of the rocker pads for wear. 3 L / M . . 09.96 73 74 M 07.00 Cylinder head M 07.10 Air-cooled engines

head and the piston at TDC. Note: This gap should be re-measured when ever a cylinder, piston, conrod, crankshaft or crankcase is renewed. Measure at all cylinders, with cold engine. – Clamp the cylinder down with a suitable tensioning strap, and use a depth gau- ge; see Fig. 75. – Turn the engine over until the piston reaches and passes through top dead centre (TDC). – Measurement „a“ plus the thickness of gasket „b“ yields the gap dimension „S“ stated in Section 4; see Fig. 76. 3 L / M . . 09.96 75 76 a b S

thickness, coat it with a little grease on the cylinder head side, and place it in the centering collar on the cylinder head. Note: Centering on the L 30 is not by means of a centering collar but with centering slee- ves; the gasket has two centering holes; see Fig. 77. – Insert the protective tubes (78/1) with spring (78/2), thrust rings (78/3) and O-ring seals (78/4) into the bore in the crankcase. Note: Always renew the O-ring seals (78/4) du- ring cylinder or cylinder head repairs. – Insert the pushrods (78/5). – Attach the cylinder head, making sure that the protective tubes with O-ring seals enter the corresponding holes in the cylinder head correctly; see Fig. 79. – Oil the stud bolt threads (79/1) and screw on the shouldered nuts. Note: Apply sealant D or a permanently elastic sealant to the thread of stud bolt (79/2) and the shouldered nut contact face (79/3). 3 L / M . . 09.96 77 78 79

sting evenly on the cylinder, but without final tightening. – Align the cylinder head by attaching the exhaust manifold; see Fig. 80. – Install the support plate and the injector centering flanges. – Tighten the cylinder head uniformly, in a cross-wise pattern, to the specified tor- que. – Take off the exhaust manifold, attach the gaskets and install it again. – Adjust valve clearances to the specified values. – Further installation work is as described for removal, but in the reverse order. 3 L / M . . 09.96 80

Preparations: – Removing cylinder head - see M 07.10. Dismantling cylinder head: – Place the cylinder head on the cente- ring collar. Note: On the L 30, pull out the centering slee- ves (81/1). The cylinder head sealing face must not be scratched or otherwise damaged; al- ways use a soft cloth or similar underlay. – Remove circlip (81/2) and pull off rockers with shims (81/3). – Press spring plate (81/4) down with tool - 6 - and remove the valve spring collets (81/5). – Take out the valve springs with underlay washers (81/6) and lift off the rocker housing (81/7). – Lift off the intermediate plate (81/8) and take out the valve cone. Checking parts: – Check the valve guides and valve stems for score marks and correct dimensions; for values, see Section 4. – Inspect the cylinder head for cracks (in the metal webs) or an uneven sealing surface. – Renew the O-ring seals (81/9); on the L 30, seal them with silicone. – Check the valve seat rings and valve cones for wear; for valve recess into cylinder head, see Section 4. – Check correct dimensions of rocker bushing, rocker shaft and rocker pad radius; for values, see Section 4. 3 L / M . . 09.96 81 M 07.00 Cylinder head M 07.20 Overhauling cylinder head (air-cooled engines)

– If necessary, use a pressing-in tool - 1 - to force out the valve guides; see Fig. 82. – Use the pressing-in tool again to insert the new valve guides - 1 -. Note: The correct pressing-in depth must be complied with; for projection, see section 4. – Using a hand-held reamer - 2 -, ream out the valve guides to their nominal diameter; see Fig. 83. – Re-machine the valve seats with a valve seat milling cutter; see Fig. 84. Note: The valve seat must always be re-machi- ned after installing new valve guides or before installing new valves, but no more metal than absolutely necessary (no pat- ches anywhere on circumference of valve seat). 3 L / M . . 09.96 82 83 84

Lap the valve cones with grinding paste (grade: 180-250). Note: To check the lapped valve seats, clean the valves, insert them and pour a small amount of diesel oil into the inlet and ex- haust ports. No fuel should seep through the valve seats. Assembling the cylinder head: – To assemble the cylinder head, follow the dismantling instructions in reverse as appropriate. Note: – Engines built in 1979 - 1983 have one spring per valve; from 1984 onwards, two springs per valve were installed. If repair work is carried out in this area, the second valve spring should be retro- fitted. – On M 31/M 40 engines up to 2300 rpm, cylinder heads with the code letter „H“ (high swirl) are used; above 2300 rpm the cylinder head code letter is „L“ (low swirl).These code letters are stamped in the inlet port. – On engines built from mid-1986 on with a running speed below 2300 rpm the longitudinally slotted rocker and valve stem seal adjusting screws are used; these screws were installed on all engi- nes from mid-1989 onwards. Retrofit these screws if repairs are carried out. – Before pressing on the valve stem seals, insert the valves into the valve guides. Press the seals on with assembly tool - 7 -. 3 L / M . . 09.96

lant lines from the cylinder head. – Take off the exhaust system and ex- haust manifold. – Take off the air cleaner and detach the air intake flange. – Remove the injectors. Dismantling: – Take off the cylinder head cover; Fig. 85. – Slacken off the shouldered nuts by half a turn (85/4) in the reverse order shown in Fig. 86 or 87. – Unscrew and remove the nuts in the same order. Unscrew the hex nuts (85/5) with spring washers (85/6) and take off the rocker pedestals. – Lift off the cylinder head. – Take off the pushrods and protective tubes. – Take off the cylinder head gasket and sealing rings. Checking the cylinder head: – Visual inspection for cracks in webs. – Visual inspection of cylinder head sea- ling face for unevenness. – Check pad radius on rockers for wear. 3 L / M . . 09.96 85 86 87 M 07.00 Cylinder head M 07.30 Water-cooled engines (H.L 30)

head and cylinder. Clean the cylinder. – Install a new cylinder head gasket (88/1) and sealing rings (88/2). – Insert the protective tubes (88/3) with springs (88/4), thrust rings (88/5) and new sealing rings (88/6) into the bore in the crankcase. Grease the sealing rings slightly. – With the aid of a second person, place the cylinder head in position, making sure that the protective tubes with O-ring seals enter the holes in the cylinder head correctly. – Insert the pushrods. – Install the rocker pedestals. Make sure that the adjusting screws are inserted correctly into the pushrods; if necessary, unscrew them. – Coat the thread of the tierod in the oil cavity with sealant D. – Screw on the shouldered nuts and tigh- ten them by hand in the order 1 - 15 (Fig. 86 or 87) until they are firmly against the cylinder head. – Tighten nuts 1 - 15 to half the specified torque. – Tighten nuts 1 - 15 to the full specified torque. – Adjust valve clearances. Note: The valve clearance for engines with alu- minium pushrods is 0.40 mm, for engines with steel pushrods 0.20 mm. – Further installation is by following the re- moval instructions in the reverse order. 3 L / M . . 09.96 88

Preparations: – Remove the cylinder head; see M 07.30. Dismantling the cylinder head: – Remove the circlips (89/10) from the rocker pedestal and pull off the rocker (89/11) with shim washers (89/12). – Pull out the centering sleeves (89/1) and place the cylinder head on its sealing surface. Note: Do not scratch or otherwise damage the cylinder head sealing face; always place a soft cloth or similar underlay beneath it. – Press the spring plate (89/2) down with tool - 6 - and remove the valve spring collets (89/3). – Take out the valve springs (89/4) with underlay washers (89/6). Note: Engines with a running speed of less than 2300 rpm are equipped with adjusting screws with longitudinal slots for the rockers (89/13) and valve stem seals (89/5). You are recommended to retrofit these screws during subsequent repair work. Engines built up to and including 1983 (all running speeds) have single valve springs. During repairs you are recommended to install double valve springs on engines which run at more than 2300 rpm. – Place the cylinder head on the exhaust side and pull out valve cones (89/16 and 17). – Take off cover (89/7) with sealing ring (89/8) and take out thermostat (89/9). 3 L / M . . 09.96 89 M 07.00 Cylinder head M 07.40 Reconditioning the cylinder head (water-cooled engines)

for rocker (89/14), rocker shaft (89/15) and rocker pad radius. For values, see Section 4. – Check valve guides and valve stems for wear; see Section 4. – Inspect the cylinder head for cracks (in webs) and unevenness of the sealing surface. – Examine the valve seat rings and valve collets for wear. Note valve recess in head; see Fig. 90 and Section 4. Reconditioning cylinder head: – If necessary, press the valve guides out with pressing-in tool - 1 -, Fig. 91. – Press in new valve guides with the same tool - 1 -. Note: The pressing-in depth must be correct; for projection, see Fig. 92. – Ream out the valve guides to nominal diameter with hand-held reamer - 2 -, Fig. 91. – If the valve seats are leaking or have been damaged locally, or after installing new valve guides, they must be rema- chined. This is carried out with special milling cutters which are available com- mercially. – Only mill away sufficient metal to elimi- nate patches on the surface of the valve seat. – After this, lap in the valves (with grin- ding paste, grain size 180 - 250); see Fig. 91. 3 L / M . . 09.96 90 91 92

and install the valves, then pour a small quantity of diesel oil into the inlet and exhaust ports. No diesel oil should seep through past the valve seats. – Note correct valve recess measurement; see Fig. 90 and Section 4. Assembling cylinder head: The cylinder head is assembled by follo- wing the removal procedure in the reverse order. Before pressing on the valve stem seals, insert the valves into the valve guides. Press the seals on with assembly tool - 7 -. 3 L / M . . 09.96

Preparations: – Take off the timing case cover; see M 11.00. Dismantling: – Take out the machine screws (97/1) and lift off the oil pump. – If necessary, pull out needle roller bea- ring (98/1) with an internal puller. Checking / repairs: – Examine the contact face for the shaft sealing ring for score-marks. If the contact face is worn, a „wear sleeve“ can be pushed over it. Use sea- lant E for this purpose. Installation instructions are included with the spare part. Assembly: – Using a plastic-faced hammer, drive the needle roller bearing flush into the crankcase. – Insert the oil pump with bearing journal into the needle roller bearing and place it over the centering sleeves. – Insert and tighten the machine screws. Note: – Apply sealant D to the machine screw for hole (98/2). – Coat the endface of the oil pump which is in contact with the crankcase with sealant B. – Re-assemble the engine in the reverse order for dismantling. – When renewing the oil pump, make sure that the correct type is installed (2- / 3- or 4-cylinder engine). 3 L / M . . 09.96 97 98 M 10.00 Oil pump

– Unscrew the oil pressure sensing switch and connect an oil pressure gauge with flexible hose - 13 - . – Install the side panel and hood to enclosure. – Start the engine and compare the oil pressure when it is at regular operating temperature with the values in Section 4; see Fig. 99. – Before assembly, coat the thread of the oil pressure sensing switch with sealant D. 3 L / M . . 09.96 99

see A 03.00. – Take off the air guide housing; see M 35.00 (engines with enclosure only) – Take off the fan; see M 13.00. – Take off the engine shutdown device; see M 20.00. Dismantling Timing cover without hydraulic pump drive: – Pull the hose off the crankcase breather valve (100/1). Note: From 2 L 40.14, 3/4 L 40.13, M 41 and on the M 31, M 40 and M 41 the hose con- nection (101/2) for the crankcase breather has been moved to the top of the crankca- se. The valve (101/1) was bonded into the air intake pipe until early 1987. Since then it has been secured in the air intake pipe by two O-rings. – Remove the circlip (102/1) and coil spring (102/2) from the pull rod of the engine shutdown device. From early 1996 an additional cup spring and an O-ring have been installed to seal the pull rod. – Unscrew and remove the belt pulley (102/3) and the machine screws holding the timing cover. – Pull off the timing cover and remove the gasket. Checking parts: – Check the timing cover for cracks or un- evenness of the sealing surface. – Examine the shaft sealing ring for dama- ge and renew if necessary. – Press off the breather valve cap and examine the diaphragm for damage. 3 L / M . . 09.96 100 101 102 M 11.00 Timing cover

Additional work: – Take off the hydraulic lines and hydrau- lic pump. – Pull out the driver (103/1). – Remove both machine screws (103/2) including spring washer (103/3), plate (103/4) and gasket (103/5). – After removing the timing cover retai- ning screws (103/4) and taking off the timing cover (103/6) the support mount (103/9) is exposed and can be taken off after removing the two screws (103/7) with spring washer (103/8). Note: – On older L 30/L 40 / H.L 30 engines there is no support mount for the hy- draulic pump drive. – H2L30 and H3L30 engines do not have a hydraulic belt tensioner. For this rea- son the pull rod is locked out of action by a hoop. A blank cover is fitted in place of the shutdown device; see Fig. 104. Assembling: – Apply grease to the contact edge of the shaft sealing ring. – Before fitting, coat new seals on both sides with sealant H. – Install the timing cover. – On the 2 and 3 L ... insert M 8 x 12 machine screws into holes (105/1) and (105/2) with sealant D. 3 L / M . . 09.96 103 104 105

gine assembly procedures are as descri- bed for removal, but working in the re- verse order. Note: When renewing the breather valve, secure the new valve housing in the insert (105/3) with sealant E and then seal all around with sealant H. If the insert is renewed, use sealant C for bonding in. The hose spigot opening in the air intake pipe must face toward the intake port of cylinder 1. The position of the opening can be varied by inserting or removing spacing washers (only on engines with crankcase breather in timing cover). 3 L / M . . 09.96

panel; see M 35.00. – On 2-cylinder engines, detach the oil fil- ler pipe. Dismantling: – Remove the screws for the extra-fuel device and take it off; see Fig. 106. Dismantling the hydraulic extra-fuel device: – Take off the circlip (106/1), unscrew the threaded pin (106/2) and push out cylin- der (107/1). – Take off the circlip (107/2) and pull out the end cover (107/3) and the piston (107/4) with spring (107/5). – Take out circlip (107/6) with spring plate (107/7), spring (107/8) and ball (107/9). Inspection / repair: – Inspect the piston and cylinder of the extra-fuel device for score-marks or worn areas. – Check the ball seat of the pressure relief valve for wear marks. – Renew the O-ring seals. Assembling the hydraulic extra-fuel device: – Assembly is as shown in Fig. 107, working in the reverse order of dismantling. 3 L / M . . 09.96 106 107 M 12.00 Extra-fuel device M 12.10 with injection pump PFR 1K 80

– After assembly, check free movement of the extra-fuel device's piston by pul- ling it out and letting it slide back; see Fig. 108. Attaching: – The extra-fuel device is installed by fol- lowing the removal instructions in the opposite order, taking particular care that the gasket is correctly installed as shown in Fig. 109 and the scribed mark is noted. Apply sealant H to both sides of the gasket. Only a thin coat should be applied, so that the oily in the extra- fuel device is not blocked. Install the machine screws with sealant D. Adjusting the extra-fuel device: – Piston (107/4) also acts as the full-load stop for the governor lever and is eccentrically located in the cylinder (107/1). The effective stroke and, therefore, the maximum injected fuel volume are adjusted by turning this cylinder. For effective stroke requirements and ad- justing procedure, see M 14.00. If the same extra-fuel device is detached and re-attached, the effective stroke does not have to be adjusted, provided that the setting of the volume limiting eccentric was not altered. 3 L / M . . 09.96 108 109

Preparations: – see M 12.10. Dismantling: – Pull terminal 7 off the solenoid valve (only version with electric engine shut- down). – Remove the screw (111/28) with sealing rings (111/36). – Make a scribed mark on the crankcase and the monitoring block, so that the monitoring block can later be re-atta- ched in the same position as before, and the original power setting is there- fore retained. – Take out the retaining screws (111/5) and take off the engine monitoring block. Dismantling the engine monitoring block: – Unscrew and remove the cover (111/9) with sealing ring (111/10); on version with electric engine shutdown, unscrew the solenoid valve (110/21) and take it off complete with sealing ring (110/23), armature (110/24) and spring (110/25). – Remove the screw plug(111/8). – Take off the lock washer (111/26), pull up shaft (111/12) take out lever (111/15), drive out locking collet (111/14) and remove shaft (111/12) from the housing. – Remove circlip (111/22); hold eccentric (111/21), slacken off grub screw (111/17) and pull out the eccentric with springs (111/20,25) and piston (111/18). 3 L / M . . 09.96 110 111 M 12.00 Extra-fuel device M 12.20 with injection pump PFR 1K 90

wear. – Check the valve seat (111/19) for wear. – Renew the O-rings. Assembling the engine monitoring block: – Proceed in the reverse order of work for removal. Note: To install the piston, use auxiliary bushing - 34 -. Assembly: – Move the speed control lever to the „Stop“ position. – To attach, follow the instructions for de- taching the device in the reverse order. – Make sure that the gasket is correctly seated and note the scribed mark which indicates the correct position; install the machine screws with sealant D. Note: When attaching, make sure that lever (112/1) engages to the left of plate (112/2). To do this on engines with the lo- wer idle speed governed to ≥1700 rpm the shaft (111/12) must be turned coun- ter-clockwise when assembling. Check when the monitoring block is installed by turning shaft (111/12) counter-clockwise; it must then move back by itself to its initi- al position. Adjusting the engine monitoring block: – The maximum fuel injection volume is adjusted by turning the piston (111/18). For adjusting the fuel injection volume and the correct procedure see section M 14.00. If the same monitoring block is detached and re-attached, the fuel in- jection volume does not need to be ad- justed, provided that the setting of piston (111/18) was not altered. If the monitoring block is renewed or after it has been repaired, the fuel injection vo- lume (power setting) must always be adjusted. 3 L / M . . 09.96 112

Preparations: – see M 12.10. Dismantling: – Detach plug connector (164/1) from engine wiring harness (electric version only). – Take out machine screws (164/3) and detach cover (164/4) and solenoid valve (164/5) with gasket (164/6) – Make a scriber mark on the crankcase and the servo block to ensure that they are installed again in the same relative positions and the power setting there- fore remains unchanged. – Remove machine screws (164/2) and take off the servo block. Inspection / repair: – Turn lever (165/1) in the „Start“ direc- tion. Shaft (165/2) is then turned by locking pin (165/3) and the sickle-pat- tern lever (165/4) moved to the starting position. When the lever is released, all elements must return to the „Stop“ position (Fig. 166). Ensure free movement if necessary by greasing or oiling lightly. – Press piston (167/8) by hand in the „Start“ direction: The sickle-shaped lever must move to the starting position, but return to the „Stop“ position when the piston is relea- sed. 3 L / M . . 09.96 164 165 166 M 12.00 Extra-fuel device M 12.30 with PFR 1K 90 injection pump (from L / M 31.12, M 40.16, 2 L 40.19, 3-4 L 40.18 and L / M 41)

– Take off lock washer (164/7) – Hold piston (164/8), raise shaft (164/9) and take out sickle-shaped lever (164/10). – Release piston (164/8) carefully and take it out of the housing. – Drive out locking collet (164/11) and pull shaft (164/9) out of the housing. – Take out grub screw (164/12). – Remove circlip (164/13) and take out washer (164/14) and eccentric disc (164/15). Inspection / repair: – Examine piston to wear score marks. – Renew gaskets. Assembling the servo block: – Assemble in the reverse order of work for removal. When installing the piston, use bushing - 34 -. Note correct position of gasket (164/6) (oil hole). Apply sealant D to machine screws (164/3) and tighten them to a torque of 6.5 Nm. Attention: If the tightening torque is too high, the servo piston may seize (distortion). Assembling: – Set the speed control lever to „Stop“. Make sure that the gasket is installed in the correct position (oil hole) and that the scriber markings are aligned. Insert machine screws (164/2) using sealant D and noting their correct posi- tions; attach a lead seal. 3 L / M . . 09.96 167 Attention! The sickle-shaped lever must never be under or to the right of the stop. – Screw the block on tightly. – Set the speed control to the „Start“ po- sition and move piston (167/8) back and forth between the start and stop posi- tions. With the injection pump removed or the side cover taken off, the governor lever can be seen to perform the same movement.

(Fig 168) – without electric control: – Valve pin 2 is in the rest position; the connection between bores 3 and 4 is closed. – Apply the electric current to connection „7“ (yellow wire): the valve pin must extend by approx. 6 mm. F » 15 - 20 N (loading can easily be overcome with the finger), free passage between bores 3 and 4. – Apply the electric current to connection „3“ (green wire): the valve pin must extend fully. F » 30 - 50 N (very difficult to overcome loading with finger pressure), free pas- sage between bores 3 and 4. – If any repairs are made to the wiring, make sure that the plugs are wired up correctly (Fig. 169). Note: When installing the valve solenoid or cover (164/4), note the corrct installed position (this also applies to the gasket); holes 168/3 and 5 must be aligned. 3 L / M . . 09.96 168 169