Home » Duramax LLY » Duramax LLY – FRONT COVER AND TIMING CHAIN – Front Cover Installation

Duramax LLY – FRONT COVER AND TIMING CHAIN – Front Cover Installation

1. Install new camshaft thrust plate and spacer if required.

2. Clean front cover and engine block sealing surfaces with carb cleaner and wipe dry.

3. Install drive keys in camshaft and crankshaft. Be sure keys are seated.

4. Assemble and install timing chain and sprockets (Figure 2-26). Check timing mark alignment before

5. Install injection pump drive gear on camshaft (Figure 2-26). Timing mark on gear should be facing
upward (12 o’clock position). Then install drive gear attaching washer and bolt. Tighten bolt to 55-60 lb-ft (75-81 N.m) torque.

6. Install new seal in front cover with tool J Ð22102.

7. Apply sealer to front cover as follows:
– Use anerobic sealer, such as Loctite 510, on cover surfaces that contact engine block.
– Use RTV-type sealer, such as Loctite 592, on oil pan and oil pan contact surface of front cover.
– Refer to sealer application diagram (Figure 2-27).

8. Install front cover on engine block (Figure 2-28). Be sure cover is fully seated on engine block dowels, engine block, and oil pan, before installing cover bolts.

9. Install front cover attaching bolts. Then tighten bolts as follows:
– Tighten cover-to-engine block bolts to 33 lb-ft (45 N.m) torque.
– Tighten oil pan-to-front cover bolts to 4-10 lb-ft (5-14 N.m) torque.

10. Install injection pump gasket on front cover studs (Figure 2-28:).

11. Install baffle in front cover (Figure 2-29). Maintain minimum clearance of 0.040 in. (1.02 mm) between baffle and injection pump drive gear. Tighten baffle attaching bolts/nuts to 33 lb-ft (45 N.m) torque.

12. Install fuel injection pump driven gear on pump shaft as follows:
a. Align timing marks on drive and driven gears and install driven gear on pump shaft.
b. Verify timing mark alignment. Drive gear mark should be at 12 o’clock position and driven gear mark
at 6 o’clock position.
NOTE: If timing marks are not perfectly aligned, turn the pump shaft to correct alignment. Do not turn the gears.
c. Install and tighten driven gear attaching bolts to 13-20 lb-ft (18-27 N.m) torque.

13. Check alignment of timing marks on front cover and injection pump flange. Rotate pump to align if necessary.
Then install pump attaching nuts.

14. Secure fuel injection pump to front cover. Tighten pump attaching nuts to 13-20 lb-ft (18-27 N.m) torque.

15. Lubricate front cover seal lip with engine oil, or petroleum jelly. Then lubricate seal contact surface of torsional damper with engine oil. Be sure seal contact surface of damper is smooth and free of burrs, nicks, or corrosion.

16. Install damper drive key in crankshaft slot. Be sure key is fully seated.

17. Install torsional damper. Then install damper attaching washer and bolt. Tighten bolt to 140-160 lb-ft (190-217 N.m) torque.

18. Install crankshaft pulley. Tighten pulley bolts to 48 lb-ft (65 N.m) torque.

19. Install coolant crossover and oil filler neck. Tighten crossover bolts to 31 lb-ft (42 N.m) torque and filler neck attaching nut to 13-20 lb-ft (18-27 N.m) torque.

20. Apply bead of anaerobic sealer, such as Loctite 510, to water pump and adapter plate. Refer to Figure 2-36 for sealer application.

21. Install water pump and adapter plate. Apply Permatex/
Loctite pipe sealing compound, to fastener that goes in hole ÒAÓ (Figure 2-30). Tighten pump/adapter bolts to 13-20 lb-ft (18-27 N.m) torque.

22. Install fan pulley, fan, and fan clutch. Tighten attaching nuts to 15-20 lb-ft (20-27 N.m).

23. Install serpentine drive belt.

24. Connect heater and bypass hoses at water pump and crossover. Then attach radiator upper inlet hoses to inlet tube.

25. Install radiator and shroud (Figure 2-21). Then install air conditioning condenser and power steering fluid cooler.

26. Connect radiator upper and lower hoses.

27. Fill cooling system.

28. Connect battery negative cables.

29. Evacuate and recharge air conditioning system if necessary.

30. Start and run engine to verify proper operation. Purge air from cooling system (if necessary), and top off coolant level at surge tank.

31. On turbo diesel, reprogram TDC offset. Refer to procedure at end of this section.


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