Hummer H1 (1992-1998). Manual - part 48

Change 1

2-155

2 - 4 1 . ENGINE ASSEMBLY FROM SUBASSEMBLIES (Cont’d)

CAUTION

Bearing caps are numbered 1 through 5 and must be installed 
in correct order, starting with number 1 at front of cylinder block.
Arrow on bearing cap must point forward or engine damage 
will result.

5.

Install bearing cap (3) on cylinder block (6) with two long capscrews (1) and short capscrews (2).
Tighten capscrews (1) and (2) finger tight.

6.

Tighten all long capscrews (1) to 110 lb-ft (149 N

•

m). Tighten all short capscrews (2) to 100 lb-ft 

(136 N

•

m).

7.

Remove two long capscrews (1), short capscrews (2), and bearing cap (3) from cylinder block (6).

8.

On edge of envelope (9) there is a scale which is graduated in thousandths of an inch. Without
removing gauging plastic, measure its thickness at the widest point with scale on envelope (9).

9.

If gauging plastic tapers toward the middle or ends, there is a difference in clearance indicating 
taper, low spot, or irregularity of bearing or crankshaft journal. If gauging plastic indicates more 
than 0.001 in. (0.025 mm) taper, measure crankshaft journal with micrometer (para. 2-17).

NOT E

If unable to obtain the proper crankshaft journal clearance, it is
acceptable to use a standard bearing with a 0.0005 in. (0.013 mm)
or 0.001 in. (0.025 mm) undersize bearing to produce clearance. 
If unable to produce proper clearance, replace crankshaft.

10.

If the measurement is within the specifications of 0.002-0.004 in. (0.051-0.102 mm), go to step 11.
If measurement is not within specifications, a 0.0005 in. (0.013 mm) or 0.001 in. (0.025 mm) under-
size bearing may produce proper bearing clearance. Replace bearings and repeat steps 4 through 10.

11.

Repeat steps 4 through 10 for remaining main bearings.

2-156

Change 2

2-41. ENGINE ASSEMBLY FROM SUBASSEMBLIES (Cont’d)

W

WA

AR

RN

NIIN

NG

G

Crankshaft must be supported during removal and installation.
Failure to support crankshaft may cause injury to personnel or
damage to equipment.

C

CA

AU

UT

TIIO

ON

N

Bearing caps are numbered one through five and must be
installed in correct order, starting with number one at front of
cylinder block. Arrow on bearing cap must point forward or engine
damage will result.

12.

After all main bearing clearances have been set, remove crankshaft (7) and gauging plastic and
apply OE/HDO to all main bearings. Install crankshaft (7), all bearing caps (1), (2), and (3), long
cap-
screws (4) and short capscrews (5). Tighten long capscrews (4) and short capscrews (5) to 12 lb-ft 
(16 N

•

m).

13.

Tap crankshaft (7) rearward, then frontward; this will align main bearing thrust surfaces (6).
Tighten long capscrews (4) and short capscrews (5) to 40 lb-ft (54 N

•

m).

14.

Tighten all long capscrews (4) to 110 lb-ft (149 N

•

m). Tighten all short capscrews (5) to 100 lb-ft

(136 N

•

m).

15.

Rotate crankshaft (7) to ensure crankshaft (7) rotates freely.

16.

Force the crankshaft (7) to the extreme front position and hold in place. Measure end play at the
front end of the number three bearing with a feeler gauge. End play should be 0.004-0.010 in.
(0.101-0.250 mm).

N

NO

OT

TE

E

• Perform steps 17 through 24 for 6.2L engines ONLY when

using a 2-piece nylon rope type rear main seal.

• Perform steps 17 and 21 through 24 when using a 2-piece

rubber rear main seal.

17.

Remove long capscrews (4), short capscrews (5), bearing caps (1), (2), and (3), and crankshaft (7)
from cylinder block (8).

18.

Apply adhesive to seal groove in rear main bearing cap (1) and cylinder block (8).

19.

Install rear main oil seal (9) into cylinder block (8) and rear main bearing cap (1) using seal installer.

20.

Cut excess oil seal (9) off flush with bearing cap (1) and cylinder block (8) mounting surface.

21.

Repeat steps 4 through 10 to ensure rear oil seal (9) did not affect rear main bearing clearance.
If bearing clearance changed, remove bearing cap (1) and inspect rear oil seal (9).

22.

Remove gauging plastic.

23.

Install number three bearing cap (3), two long capscrews (4), and short capscrews (5). Tighten
capscrews (4) and (5) to 12 lb-ft (16 N

•

m).

24.

Tap crankshaft (7) rearward, then frontward; this will align main bearing thrust surfaces (6).
Tighten capscrews (4) and (5) on number three bearing cap (3) to 40 lb-ft (54 N

•

m).

N

NO

OT

TE

E

Immediately install rear main bearing cap after application of
sealant.

25.

Apply thin film of sealer to rear main bearing cap (1) mating surface. Keep sealer off bearing and
oil seal (9) (installed on 6.2L engines).

26.

Install rear main bearing cap (1) on cylinder block (8) with long capscrews (4), and short cap-
screws (5). Tighten capscrews (4) and (5) to 40 lb-ft (54 N

•

m).

2-41. ENGINE ASSEMBLY FROM SUBASSEMBLIES (Cont’d)

27.

28.
29.

30.

31.
32.

Install remaining bearing caps (2) on cylinder block (8) with long capscrews (4) and short
capscrews (5). Tighten capscrews (4) and (5) to 40 lb-ft (54 N•m).
Evenly tighten all long capscrews (4) to 110 lb-ft (149 N•m).

Evenly tighten all short capscrews (5) to 100 lb-ft (136 N•m).

NOTE

Perform steps 30 through 32 for 6.5L engines.

Coat rear crankshaft (7) surface with engine oil, and lightly coat lip of rear main oil seal (9) with
engine oil.
Insttall rear main oil seal (9), with spring Cavity towards cylinder block (8), on crankshaft (7).
Using seal installer, drive rear main oil seal (9) in until tool bottoms against cylinder block (8) and

2-157

2-41. ENGINE ASSEMBLY FROM SUBASSEMBLIES (Cont’d)

1. Install flywheel (3) on crankshaft (4) so that converter mounting surface (2) faces outward.

2. Secure flywheel (3) to crankshaft (4) with six capscrews (1). Tighten capscrews (1) to 65 lb-ft

(88 N•m).

2-158