Hummer H1 Service Manual page 61

_____________________________________________________________________
2-24 Engine
CROSSOVER
OIL
FILLER
NECK
Figure 2-22: Upper Radiator Hose Connections
11. Remove fan and fan clutch.
12. Remove crankshaft pulley (Figure 2-14).
13. Remove torsional damper attaching bolt and washer
(Figure 2-17).
14. Remove torsional
(Figure 2-18).
15. Remove drive keys from crankshaft. Replace keys if worn,
chipped, or distorted.
16. Remove water pump and adapter plate as assembly
(Figure 2-23).
17. Remove bolts that attach front cover to oil pan
(Figure 2-24).
18. Rotate crankshaft by hand until timing marks on sprockets
and gears are aligned and number one piston is at TDC.
ADAPTER PLATE
Figure 2-23: Water Pump and Adapter Plate Removal/Installation
Ð
damper with tool J
19. Remove injection pump driven gear (Figure 2-24).
HOSE
20. Remove baffle from front cover (Figure 2-24).
21. Remove nuts and washers attaching fuel injection pump to
studs on front cover (Figure 2-24).
NOTE: There are timing marks on the front cover and injec-
tion pump. Note position of these marks for installation refer-
ence.
22. Remove bolts that attach front cover to engine block. Then
break sealer bead with putty knife and remove cover.
23. Cover oil pan opening to prevent dirt entry.
24. Check timing chain deflection with dial indicator.
Measure deflection mid-way between crankshaft and cam
sprockets. Maximum allowable deflection is 0.810 in.
(20.5 mm). Replace chain and sprockets if deflection is
greater than specified.
25. Check camshaft end play with dial indicator. Maximum
allowable end play is 0.012 in. (0.3 mm). Replace cam
thrust plate and spacer if end play is greater than specified.
NOTE: Note position of timing marks on drive gear and crank
23523-F
and cam sprocket for installation reference.
26. Remove bolt and washer attaching injection pump drive
gear to camshaft. Then remove gear (Figure 2-25).
27. Slide timing chain and sprockets off camshaft and
crankshaft (Figure 2-25).
28. Remove drive keys from camshaft and crankshaft.
Replace keys if chipped, cracked, or distorted. Minor burrs
can be removed with a stone or fine tooth file.
29. Clean all old sealer off engine block, front cover, and
water pump/adapter plate with scraper.
WATER PUMP
¨
FRONT COVER