Hummer H1 (2002+). Manual - part 10

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2-1

05745159

Section 2 Engine

INTRODUCTION

This section contains general information, diesel engine diagno-
sis, turbocharger service, and diesel engine repair and overhaul.

A table of contents is provided that lists the various repair
items and the section page number where repair information is

located. Use the contents tables to avoid random searches for
needed information.

Specifications for diesel engines are located at the end of this
section for quick reference. Service tool information can be
found at the end of the Engine section.

TABLE OF CONTENTS

A/C Compressor Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-50
Boost Pressure Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-16
Camshaft

Bearing Replacement  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-64
Installation  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-85
Removal  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-59
Timing Chain, Sprocket and Drive Gears  . . . . . . . . . . . . .2-71

Crankshaft

Cylinder Block

Cylinder Bore and Piston Measurement . . . . . . . . . . . . . .2-62
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-60

Cylinder Head

Cylinder Head And Gasket Service  . . . . . . . . . . . . . . . . . .2-37
Installation  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-89
Overhaul . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-72
Removal  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-55

Damper and Flywheel Service . . . . . . . . . . . . . . . . . . . . . . . . . .2-76
Engine

Engine Assembly and Adjustment

Crankshaft and Main Bearing Installation. . . . . . . . . . . . . 2-80
Crankshaft Main Bearing Selection . . . . . . . . . . . . . . . . . . 2-80

Exhaust Manifold

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-92
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-51
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-35

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-92
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-53

Fuel Injection Pump

Fuel Supply and Return Line Removal . . . . . . . . . . . . . . . 2-53
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-87
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-56

Glow Plug

Glow Plug Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-54
Glow Plug Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Glow Plug and Injection Nozzle . . . . . . . . . . . . . . . . . . . . . 2-90
Operation and Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6

Intake and Exhaust Manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . 2-79
Intake Manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-43

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-52

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
In-Vehicle Service, Diesel Engine . . . . . . . . . . . . . . . . . . . . . . . 2-19
Lifter, Pushrod, Rocker Arm Service . . . . . . . . . . . . . . . . . . . 2-76
Lubricants/Sealants/Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Oil Filter

Adapter Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-78
Filter, Adapter, Fittings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-87

Oil Filter/Adapter/Oil Pressure Sending Unit . . . . . . . . . . . . . . 2-57
Oil Pan Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-58

2-2

Engine

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Oil Pump

Oil Pump and Drive Removal . . . . . . . . . . . . . . . . . . . . . . .2-58
Oil Pump and Pump Drive Service. . . . . . . . . . . . . . . . . . .2-77
Oil Pump Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-22
Oil Pump Pressure. . . . . . . . . . . . . . . . . . . . . . . . . . . . Test 2-7
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-28

Oil Pump, Oil Pan, Flywheel Installation . . . . . . . . . . . . . . . . . .2-84
Piston/Connecting Rod

Installation and Bearing Fit. . . . . . . . . . . . . . . . . . . . . . . . .2-83
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-59

Piston/Connecting Rod Overhaul . . . . . . . . . . . . . . . . . . . . . . .2-67

Piston and Connecting Rod Assembly . . . . . . . . . . . . . . .2-69
Piston Ring Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-70
Piston Selection and Fit . . . . . . . . . . . . . . . . . . . . . . . . . . .2-68

Power Steering Pump and Bracket . . . . . . . . . . . . . . . . . . . . . .2-50
Pushrod, Rocker Arm and Shaft Installation . . . . . . . . . . . . . .2-90
Rear Main Oil Seal Replacement . . . . . . . . . . . . . . . . . . . . . . . .2-29
Rear Main Seal Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-82
Road Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
Rocker Arm

Cover Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-54
Cover Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-30
Shaft and Pushrod Removal. . . . . . . . . . . . . . . . . . . . . . . .2-54
Shaft and Pushrod Service . . . . . . . . . . . . . . . . . . . . . . . . .2-33

Rocker Cover Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-91

Serpentine Belt Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-49
Timing Chain/Drive Sprockets/Drive Gear . . . . . . . . . . . . . . . . 2-57
Timing Chain-Sprocket-Gear Installation . . . . . . . . . . . . . . . . . 2-85
Torsional Damper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21
Torsional Damper/Crankshaft Pulley . . . . . . . . . . . . . . . . . . . . 2-93
Turbocharger

Turbocharger and Center Manifold Removal . . . . . . . . . . . . . . 2-52
Turbocharger and Intake Manifold . . . . . . . . . . . . . . . . . . . . . . 2-93
Vacuum Pump Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-44
Valve Lifter

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-88
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-55
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-41

Water Crossover

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-92
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-52

Water Pump and Adapter Plate Installation . . . . . . . . . . . . . . . 2-87
Water Pump and Adapter Plate Removal . . . . . . . . . . . . . . . . . 2-56

ENGINE DESCRIPTION

A turbocharged diesel engine is used in Hummer vehicles. It is
a liquid cooled, four-stroke, 90¡ Ð V8 engine with a displace-
ment of 6.5L (395 cu. in.) (Figure 2-1). The engine is manufac-
tured by General Motors Corporation.

Figure 2-1: 6.5L Turbo Diesel Engine

Engine Components

The engine block and cylinder heads are cast iron. Turbo en-
gines are equipped with a three-piece aluminum intake mani-
fold and cast iron exhaust manifolds.

The oil cooling system for turbo diesel pistons provides for oil
spray onto the underside of the piston crown. This is accom-
plished by additional oil feed orifice tubes and galleries in the
block. Oil spray occurs when the piston is approaching bottom

dead center on the intake and power strokes. The extra oil pres-
sure and volume needed for piston cooling is provided by a
high output oil pump. The pump has a working pressure of 80
psi (552 kPa). Oil feed for piston spray is through galleries and
oil tubes located in the main bearing saddles and webs.

The crankshaft is supported by five insert style main bearings.
Thrust is taken by the number 3 main. The camshaft is also
supported by five bearings; plain type bearings are used.

The engine is equipped with three ring aluminum pistons. Con-
necting rods are forged steel. The pistons are attached to the
rods with hardened steel piston pins. Each piston pin is re-
tained by two snap rings; one at each end of the pin. The pin is
a floating fit in the rod and piston.

A single chain driven camshaft operates the overhead valve
train. Roller lifters and tubular push rods actuate the rocker arms.
The arms are mounted on shafts bolted to each cylinder head.

The cylinder heads are equipped with glow plugs for each cyl-
inder and a prechamber for each combustion chamber. One
plug and one prechamber are used in each combustion cham-
ber. The glow plugs heat air entering the prechambers. This
aids the combustion process and improves cold weather start-
ing and operation. The glow plugs are activated only when am-
bient temperatures fall below a pre-set value. On the turbo
diesel engine the glow plug relay is mounted on the intake
manifold and is controlled by the PCM.

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Engine 2-3

05745159

The turbocharged diesel engine is equipped with a Warner
Gear turbocharger. A wastegate, in the turbine housing, con-
trols boost. The wastegate is operated by an externally
mounted vacuum actuator. The actuator opens the gate to de-
crease boost, or closes it to increase boost. Waste gate position
is controlled by the PCM.

The turbocharger increases the amount of air entering the com-
bustion chambers. This allows a proportionate increase in fuel
injected into the cylinders. The result is a much denser cylinder
charge and greater power output.

The turbocharger turbine and compressor impellers are the
mechanisms that pump additional air into the combustion
chambers. The impeller wheels are operated by the high speed
gas flow through the engine exhaust system.

Engine lubrication is through a conventional mechanical pump
located at the rear of the crankcase. The pump is shaft driven
by the oil pump drive unit which in turn, is driven off the cam-
shaft. A belt driven vacuum pump is used on both engines.
Both versions of the 6.5L diesel are equipped with a high pres-
sure fuel injection system. The system consists of an electric
fuel supply pump, an injection pump, a separate injector nozzle
for each cylinder, and the necessary injector feed lines.

The rotary type injection pump pressurizes, meters, and distrib-
utes fuel to the individual injectors. System working pressure
is 1750 psi (120 bar) for turbocharged engines. The pump is
gear driven through matching gears on the pump and camshaft.

ENGINE IDENTIFICATION

The diesel engine I.D. decal is located on the forward face of
the passenger side cylinder head (Figure 2-2).

The decal provides the engine assembly/serial number and a
bar code. Similar decals are placed on the driver side cylinder
head and passenger side of the oil pan.

Figure 2-2: Diesel Engine I.D. Tag Location

Service Tools

The special service tools described in this section are available
through the dealer tool program.

Specifications

Engine specifications for overhaul, adjustment, inspection and
torque requirements are provided at the end of this section.

LUBRICANTS/SEALANTS/COOLANT

Engine Oil

Recommended engine oil for the GM built, diesel engines used
in Hummer vehicles, is API classification CF-4 (Figure 2-3).
Base stock or synthetic oils are equally acceptable.

Oil viscosity recommendations are:

Use 15W-40 at ambient temperatures from 0¡F
(-188¡C) to above 100¡F (401¡C).

Use 30W at ambient temperatures above 32¡F (0¡C).

Use 10W-30 at ambient temperatures below 60¡F
(165¡C).

Do not use 10W-40, or any other oil that is not specifically rec-
ommended. Use recommended oils only for lubrication pur-
poses during repair and overhaul.

AM General suggests using Quaker State FCI-Universal HDX
Engine Oil 15W-40 grade or equivalent.

Figure 2-3: Oil Viscosity Chart

ENGINE SERIAL NUMBER

BAR CODE DECAL

HOT

COLD

SAE 10W-30

SAE 15W-40

SAE 30W

WEATHER

°F

°C

+100

+36

+60

+16

+32

-18

-20

-29

PREFERRED

API CG-4, SJ/CD QUALITY PREFERRED
DO NOT USE SAE 10W-40 GRADE OIL,

OR ANY OTHER GRADE NOT RECOMMENDED

2-4

Engine

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Sealants

Anerobic, RTV, and standard sealants are all used for various
repairs.

RTV (room temperature vulcanizing) sealers are used when a
non-rigid part is attached to a rigid part (e.g. oil pan to engine
block).

Typical RTV sealers would be Permatex High Temp, Ultra
Copper, Ultra Black, or Loctite 599.

Anerobic (gasket eliminator) sealants are used where two rigid
parts are being assembled. This type of sealant cures in the ab-
sence of air. Typical anerobic sealers are Loctite 510 and 518.

Standard type sealers are used primarily as gasket dressing or
thread sealants. Typical examples would be Permatex #2, or
Perfect Seal spray sealer.

Thread locking sealants are frequently recommended for fas-
teners subject to heat and vibration. Recommended products
are:

¥ Loctite 242 for all purpose use

¥ Loctite ÒStud and Bearing MountÓ for semi-permanent

attachment

Coolant

Recommended engine coolant is an ethylene glycol base, all
weather coolant with corrosion and anti-foaming inhibitors.
All of the major brands are acceptable (i.e. Prestone, Peak,
Zerex, etc.). Do not use coolants other than ethylene glycol
based. Recycle coolant according to EPA regulations.

Do not use pure coolant in the cooling system, especially in
cold-climate regions. Recommended mix is 50% antifreeze,
50% water.

CLEANING MATERIALS

Normal parts cleaning solvents can be used for most purposes.

Use brake or contact cleaner, to clean surfaces where anaerobic
or RTV sealants will be applied. This type of solvent does not
leave a residue that interferes with sealer cure or adhesion.

Carbon deposits can be emulsified by some spray type gasket
removers. Permatex and 3M both have effective products.

Avoid using diesel fuel, gasoline, paint and lacquer thinners or
kerosene for parts cleaning purposes. These products can leave
an undesirable residue.

Cylinder and lifter bores should be cleaned with a liquid deter-
gent and warm water mixture after honing or polishing. A bris-
tle brush or cotton towel can be used to wash the bores until
clean and free of oil, dirt, and abrasive grit.

COMPRESSION TEST

Disconnect fuel solenoid wire at injection pump.

Disconnect and remove all glow plugs.

Thread adapter J

26999-30 into glow plug hole of first

cylinder to be tested. Then attach compression gauge J

26999

to adapter.

Have helper crank engine through six cycles (to generate
six compression strokes). Note and record gauge pressure.
Repeat procedure at remaining cylinders.

Minimum acceptable cylinder pressure is 380 psi (2626
kPa). In addition, lowest cylinder should be at least 80%
of highest; this is maximum allowable cylinder variance.

CAUTION:

Never inject oil into the diesel engine cylinders for

any reason. This could result in piston and rod damage be-
cause of the minimal clearances in a high compression diesel
combustion chamber.

Figure 2-4: Compression Test Tools

FUEL FILTER WARNING LAMP

All Hummer models are equipped with a fuel filter warning
lamp. The lamp is in circuit with a sensor mounted in the filter.
The purpose of the lamp is to alert the driver when water, ice,
or wax buildup occurs in the filter.

Lamp illumination can be intermittent or continuous depending
on the severity of water or wax buildup.

In most cases, continuous illumination of the lamp simply
means it is time to drain the filter. However, a continuous lamp
plus engine stall or restart problems may indicate a plugged fil-
ter or fuel lines.

Intermittent illumination of the lamp indicates that water is ac-
cumulating in the filter. In this instance, it is only necessary to
drain off the water at the wheel house draincock.

COMPRESSION

GAUGE

26999

ADAPTER

26999-30

Content .. 8 9 10 11 ..