Hummer H1 Service Manual page 74

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CYLINDER HEAD AND GASKET SERVICE
Cylinder Head (Left Side)
Removal
1. Remove hood with aid of helper as follows:
¥ Disconnect hood harness
¥ Remove harness clips at driver side frame rail bracket
¥ Remove bolts that attach prop rod bracket to driver
side frame bracket
¥ Remove hood hinge pins
¥ Lift and remove hood
2. Remove front console and engine cover.
3. Drain radiator and disconnect batteries.
4. Disconnect and cover fluid cooler lines at transmission
and power steering coolers.
5. Remove driver side splash shield.
6. Remove serpentine belt.
7. Remove air intake hose and air horn.
8. Remove A/C compressor, power steering pump, and
mounting bracket as assembly. Position A/C compressor
to side to allow access to rocker cover and cylinder head.
9. Remove oil dipstick tube, water crossover, thermostat
housing, coolant hoses, and radiator upper hose inlet tube.
10. Disconnect or remove (Figure 2-40):
¥ Heater water valve bracket
¥ Wire harness clips and brackets
¥ Ground wires/cables at rear of cylinder head
¥ Temperature sender wire
¥ Fuel pump
¥ Glow plugs
11. Remove fuel injector line clamps. Retain clamps and
attaching washers and nuts.
Figure 2-40: Ground Connections at Rear of
Cylinder Head
05745159
12. Remove intake manifold and gaskets. Note attaching stud
and bolt locations for reinstallation reference.
13. Disconnect driver side fuel injector lines at pump and
injectors and remove lines. Cover injectors with duct tape
to prevent dirt entry.
14. Remove bolts/nuts attaching crossover pipe to exhaust
manifold.
15. Remove rocker arm cover. Tap cover with rubber mallet to
loosen. Do not pry on cover to remove.
16. Remove rocker arm shaft bolts and retainers. Remove arm
and shaft assemblies individually. Note original position
for assembly reference.
17. Remove pushrods. Note position of rods for installation
reference as they must be installed in original position.
18. Remove cylinder head bolts. Discard bolts as they are not
reusable.
19. Remove cylinder head (Figure 2-41) with aid of helper, or
use chain hoist, portable hoist, or similar device to lift and
remove cylinder head.
DOWEL
Figure 2-41: Cylinder Head and Gasket
Removal/Installation
20. Remove cylinder head gasket. Discard gasket; it is not
reusable.
21. Refer to overhaul section if head, valves, valve seats,
springs, or seals require service. Check for warpage. If
head was only removed to replace blown gasket, proceed
to installation procedure.
22. Cover cylinder bores and lifter valleys with shop towels.
Engine 2-37
CYLINDER HEAD
COOLANT
TEMPERATURE
SENDER
DOWEL