Hummer H1 Service Manual page 77

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2-40 Engine
Cylinder Head (Right Side)
Installation
1. Clean gasket surface of cylinder block with scraper if nec-
essary. Scuff sand surface with 180 grit emery or paper to
provide better surface for gasket seating. Then remove
protective covering from cylinders and lifter valleys.
2. Wipe cylinder block surface clean with solvent and cloth.
3. Position new head gasket on cylinder block. Be sure
gasket is aligned on cylinder block dowels.
CAUTION: Install the new gasket dry. Do not use any type of
sealer on the gasket. Sealer can prevent proper seating and re-
sult in coolant leaks.
4. Install cylinder head with aid of helper or with hoist.
5. Install and tighten new cylinder head bolts as follows:
a. Apply light coat of sealer, such as Loctite Pipe Seal-
ant w/Teflon, to thread and under heads of new bolts.
b. Install and tighten bolts to initial torque 20 lb-ft (27
N¥m). Follow tightening sequence shown
(Figure 2-42).
c. Tighten bolts to 50 lb-ft (68 N¥m) torque evenly and
in sequence shown (Figure 2-42).
d. Final-tighten bolts an additional 90¡ (1/4-turn).
6. Install pushrods. Verify that they are in same sequence as
when removed. Also be sure heat treated end is toward
rocker arm.
7. Index crankshaft and pistons for rocker arm and shaft
installation as follows:
a. Position breaker bar and socket on crankshaft damper
bolt. Do not use starter motor to rotate crankshaft. Use
hand tools only.
b. Rotate crankshaft counterclockwise and align mark
on torsional damper with ÒOÓ (TDC) mark on front
cover timing tab (Figure 2-43).
c. Index crankshaft by rotating it counterclockwise an
additional 3-1/2 inches (89 mm). At this point, mark
on damper will be roughly aligned with first lower
water pump bolt (Figure 2-43).
8. Install rocker arm and shaft assemblies. Be sure pushrods
are properly seated in lifters and rocker arms. Do this
before tightening shaft retainer bolts. Install shaft retainers
and bolts. Tighten bolts evenly to 41 lb-ft (56 N¥m)
torque.
CAUTION: Stop tightening the shaft bolts if they become hard
to turn before they are fully seated. Check for misalignment or
unseated push rods.
9. Clean cylinder head and rocker cover sealing surfaces
thoroughly. Then finish-clean with brake or contact
cleaner and shop towels to remove residue. This is
necessary to ensure proper seal adhesion.
10. Apply sealer to rocker arm cover. Make sealer bead 3/16
inch wide by 1/16 inch thick. Use RTV-type silicone,
adhesive-sealer such as Loctite 592, or Permatex High
Temp, Ultra Copper, or Ultra Blue. Allow sealer to cure
slightly (skin over) before installing cover.
11. Align and install rocker cover. Tighten cover bolts to 16
lb-ft (22 N¥m) torque.
12. Install fuel injector lines. Tighten line fittings at pump and
injector to 19 lb-ft (26 N¥m) torque.
13. Install intake manifold and gaskets. Tighten manifold
studs/bolts to 31 lb-ft (42 N¥m) torque.
14. Install water crossover and thermostat housing. Use new
gaskets on crossover and tighten attaching bolts to 25-37
lb-ft (34-50 N¥m) torque.
15. Install or connect:
¥ Glow plugs and glow plug relay and bracket
¥ Engine harness wires, clips, and brackets
¥ Water valve bracket
16. Install and attach transmission fill tube.
17. Install heat shield and shield guard. Tighten heat shield
bolts to 25 lb-ft (34 N¥m) torque.
18. Install support bracket on rear of alternator and mounting
bracket. Then install alternator, bracket, and tensioner as
assembly. Connect alternator wires afterward.
19. Install vacuum pump.
20. Install serpentine belt.
21. Install surge tank.
22. Install air cleaner, air horn, inlet hose, and shield.
23. Assemble radiator upper hoses and tube and connect to
thermostat housing.
NOTE: Check condition of the O-rings on the A/C and oil
cooler fittings. Replace the O-rings if cut, worn, or distorted.
24. Connect radiator upper hose, heater hoses, and surge tank
hoses.
25. Refill cooling system.
26. Install passenger side splash shield. Then install battery
tray and horns (if removed).
27. Install and connect batteries.
28. Top off engine oil and transmission fluid as needed.
29. Start and run engine. Bleed injectors by loosening line
fittings just enough to purge any air. Then tighten fittings
and stop engine.
30. Top off engine coolant, oil, and transmission fluid as
required.
31. Clear codes and test drive.
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