Hummer H1 (2002+). Manual - part 20

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Engine 2-41

05745159

VALVE LIFTER REPLACEMENT

The 6.5L diesel engines are equipped with roller-type hydrau-
lic lifters. The lifters are not repairable. A failed lifter must be
replaced as an assembly.

Service access to the lifters requires removal of one or both
cylinder heads. Once the head is removed, the lifters can be re-
moved with tool J

29834.

Removal

Remove one or both cylinder heads as needed. Refer to
procedures in this section.

Remove bolt attaching guide plate clamp to block and
remove clamp (Figure 2-15).

Figure 2-46: Valve Lifter Removal

Remove lifter guide plate. Use magnet and long hand held
gripper tool to unseat and remove plate.

NOTE: If more than one lifter will be removed, keep the lift-
ers in sequence of removal. It is important that original lifters
be re-installed in the same bore. This ensures that the lifter and
cam lobe wear-in patterns will match.

Figure 2-47: Lifter Inspection Points

Remove necessary lifters with tool J

29834. Insert tool in

lifter and push tool plunger downward to expand tool lugs
and grip lifter. Then remove lifter with a pull and turn
motion.

Cleaning and Inspection

Clean each lifter with a standard parts cleaning solvent. Dry
the lifter with low pressure compressed air after cleaning.

Check the lifter body for scoring and wear. Then turn the lifter
over and check condition of the roller (Figure 2-47). Replace
the lifter if the body is worn or scored, or the roller is scuffed,
chipped, loose, or the roller bearings are worn.

Press the lifter plunger down with a push rod and note if the
plunger is collapsed. Replace collapsed lifters; they are not sal-
vageable.

Installation

WARNING: The following procedural step requires the
use of kerosene or diesel fuel for lifter priming. Since
both liquids are flammable, do not prime the lifter near
sparks, or an open flame. This is essential to ensure
personal safety and injury avoidance.

Prime lifters as follows:

Place lifter in container deep enough to submerge
lifter. Pad container bottom to avoid damaging roller.

Fill container with clean fresh kerosene or diesel fuel.

LIFTER TOOL

29834

GUIDE PLATE

CLAMP

AND BOLT

LIFTER

GUIDE

PLATE

CYLINDER BLOCK

VALVE
LIFTER

6-SO2-069

BODY

ROLLER

PLUNGER

2-42

Engine

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Stroke lifter plunger with pushrod to pump fluid
through lifter.

Remove lifter from container and wipe it dry with lint
free cloth or paper.

Re-prime lifter with clean engine oil.

Apply cam lube to lifter roller and bearings.

Install lifters as follows:

Insert lifter in bore with tool J

29834.

Align lifter and install guide plate on lifters. Be sure
lifters and plates are aligned.

Install guide plate clamp and bolt. Tighten bolt to 19
lb-ft (26 N¥m) torque.

Install cylinder head(s) as described in this section.

CRANKSHAFT BEARING

Replacement In-Vehicle

The crankshaft main and rod bearings can be replaced without
having to remove and completely disassemble the engine.

The rod bearings only require that the piston be at or near bot-
tom dead center for access. The main bearings are rotated out
of the bearing saddles with a 1/8 in. cotter pin or with equiva-
lent. Procedure is as follows:

Disconnect battery cables at batteries.

Remove skid plate/underbody protector, if equipped.

Drain engine oil from oil pan.

Remove oil pan.

Remove oil pump.

Replace rod bearings as follows:

Rotate crankshaft in counterclockwise direction until
connecting rod cap attaching nuts are accessible.

Remove rod cap nuts. Note position of rod cap for
installation reference.

Remove rod cap and lower half of bearing. Then push
piston upward slightly and remove upper half of
bearing.

NOTE: Connecting rod bearings are select fit parts. Record
the color code markings on each bearing half for parts ordering
and installation reference. Also note if cap was marked with
ÒOSÓ code which indicates oversize bearings are required.

Clean connecting rod and crankshaft bearing surfaces
and dry with lint free shop towels.

Install bearing halves in rod cap and in rod. Be sure
bearing locating tangs are seated in cap and rod
notches.

Check bearing clearance with plastigauge. Clearance
should be 0.0017-0.0039 in. (0.045-0.100 mm). Then
remove rod cap, clean plastigauge off surfaces, lubri-
cate crankshaft and bearing surfaces with engine oil

and reinstall rod cap. Tighten new cap nuts to 44-52
lb-ft (60-71 N¥m) torque.

Replace main bearings as follows:

Loosen bearing cap bolts at adjacent bearings.

Remove bearing cap bolts at first bearing to be
replaced, and remove cap and bearing lower half
(mark cap for reference before removal).

Insert tool J

8080 into oil hole in crankshaft bearing

journal. Position ÒTÓ-end of tool against bearing
upper half. Rotate crankshaft counterclockwise until
tool pushes upper half of main bearing out of bearing
saddle in block (Figure 2-48).

Clean main cap, crankshaft journal, and bearing
saddle in block with solvent. Refer to overhaul section
for bearing specifications and select fitting.

Start plain end of new upper bearing half into place by
hand. Then push bearing into position with tool
J8080. Be sure bearing tang is seated in notch in
bearing saddle of block (Figure 2-48).

Check bearing clearance with plastigauge. Clearance
should be 0.0017-0.003 in. (0.045-0.083 mm) for
bearings one through four and 0.002-0.0036 in.
(0.055-0.093 mm). Remove main cap, clean plasti-
gauge off surfaces, lubricate bearing halves and crank
journal with engine oil. Tighten new main bearing cap
bolts as follows:

inner bolts to 111 lb-ft (150 N¥m)

outer bolts to 100 lb-ft (136 N¥m)

Install oil pump.

Apply RTV-type sealer to oil pan sealing surfaces and
install pan. Tighten all but two rear pan bolts to 89 lb-in.
(10 N¥m) torque. Tighten two rear pan bolts to 17 lb-ft (23
N¥m) torque.

10. Install new oil filter and refill with engine oil. Use SAE

10W-30 for temperatures under 40¡F and 15W-40 for
temperatures above that figure.

11. Connect battery cable and reinstall skidplate.

12. Test run. Test for leaks.

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Engine 2-43

05745159

Figure 2-48: Removing/Installing Main Bearing

Upper Half with Cotter Pin or Equivalent

INTAKE MANIFOLD

Service

A three-piece intake manifold is used on turbocharged diesel
engines (Figure 2-49). It consists of left and right manifold
halves and a center manifold. The center manifold joins the
other manifold halves to the turbocharger.

Gaskets and an O-ring seal are required at the manifold-to-cyl-
inder head and manifold joints. A single O-ring is used to seal
the center manifold-to-turbocharger flange joint.

Removal

Remove turbocharger. Refer to procedure in this section
under Turbocharger Service and Diagnosis.

Remove center manifold bolts. Remove manifold from
intake manifold halves and turbocharger. Discard
manifold gaskets and O-ring seal.

Remove brackets/clamps securing wire harnesses to
rocker covers and intake manifold halves.

Remove bolts/nuts/studs attaching intake manifold halves
to cylinder heads. Tap manifolds with rawhide mallet to
loosen and remove. Discard gaskets after removal.

Installation

Clean manifold and cylinder head gasket surfaces. Apply
light coat of Permatex High Tack, or #2 sealer to gaskets
and position gaskets on heads.

Install left and right manifold halves. Tighten attaching
bolts and studs to 25-37 lb-ft (34-50 N•m) torque.

Install turbocharger and center manifold as described in
this section.

Figure 2-49: Intake Manifold Attachment

MAIN BEARING UPPER

HALF (IN BLOCK)

BEARING TANG

TOOL J–8080

INSERTED IN

OIL HOLE

CRANKSHAFT

MAIN

BEARING

JOURNAL

GASKET

CENTER MANIFOLD

O-RING

GASKET

LEFT/RIGHT

RIGHT SIDE MANIFOLD

(LEFT SIDE SIMILAR)

GASKET

MANIFOLDS

Section 2 Engine

2-44

Engine

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EXHAUST MANIFOLDS

Removal

Remove consoles and engine cover for access to turbo-
charger inlet pipes. For information regarding inlet pipes,
refer to Section 3.

Loosen flange clamps that secure left inlet pipe to exhaust
manifold and turbocharger. On right side, loosen flange
clamp and remove nuts that attach inlet pipe to exhaust
manifold. Then disconnect pipe and move aside for
working clearance.

Remove heat shield attaching nuts/bolts and remove
shield, if equipped.

Disconnect glow plug wires.

Remove manifold attaching bolts and remove manifold
(Figure 2-50).

Remove and discard manifold gasket.

Clean old gasket material off cylinder head and manifold
with scraper and wire brush.

Installation

Place new gasket on manifold, position manifold on cylin-
der head, and install 1-2 bolts to hold manifold in place.

Install heat shield and remaining manifold bolts. Tighten
bolts to 18-25 lb-ft (24-34 N•m) torque.

Connect glow plug wires.

Install flange clamps and turbocharger inlet pipes. If
installing right side manifold, tighten inlet pipe-to-
manifold attaching nuts to 37 lb-ft (50 N•m) torque.
Tighten exhaust flange clamps to 71 lb-in (8 N•m) torque.

Install turbocharger heat shields.

Install engine cover and consoles.

Figure 2-50: Exhaust Manifold Attachment

DIESEL VACUUM PUMP SERVICE

A vacuum pump is used on all diesel models.

The pump is located on the passenger side of the engine just
below the alternator (Figure 2-51).

This supplies vacuum for wastegate actuator operation on
turbo models and for A/C and heater operation on diesel mod-
els. The pump is belt driven and has a removable pulley.

The pump is tested with a standard vacuum gauge. Output
should be a minimum of 20-21 inches vacuum.

Pump removal only requires loosening the serpentine belt, dis-
connecting the vacuum output hose, and removing the pump
attaching bolts.

Figure 2-51: Vacuum Pump Location

PASSENGER

SIDE

MANIFOLD

DRIVER

SIDE

MANIFOLD

PUMP

PULLEY

VACUUM

PUMP

ALTERNATOR

SERPENTINE

BELT

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