Hummer H1 Service Manual page 47

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2-10 Engine
PROBLEM
Engine Will Not 5. Starter or solenoid problem.
Crank -
(Continued)
6. Hydrostatic lock. Combustion chambers
Þlled with fuel, or coolant due to faulty injec-
tors, or blown head gasket. (Remove glow
plugs, crank engine and note ßuid coming
out of plug holes).
7. Flywheel ring gear teeth or starter Bendix
damaged.
Engine Stalling 1. Air leaks in fuel lines.
2. Fuel Þlter partially plugged by wax forma-
tion, dirt/sludge, or partially water Þlled.
3. Misfueled, wrong fuel, or low quality fuel.
4. Restricted air intake due to plugged Þlter ele-
ment, air cleaner, intake duct. Generally
caused by extended off -road operation in
dusty areas.
5. Fuel supply pump problem or restriction in
fuel lines, injector pump, or injectors.
6. Fuel drain back or return lines restricted/
damaged.
Engine Diagnosis
POTENTIAL CAUSE CORRECTION
5. Check for bad or loose connections at starter and
solenoid. If OK, note if starter surges when current
is applied. Problem may be with Bendix or arma-
ture.
6. Test and replace injectors that are stuck open.
Replace blown head gasket or replace head if
cracked.
7. Remove transmission access cover and inspect ring
gear and bendix. Replace ßywheel or starter Ben-
dix as necessary.
1. Check lines from fuel pump to injectors. Replace
lines that leak or have damaged Þttings. Tighten
loose injectors. Bleed injectors afterward.
2. Drain off Þlter contents at draincock. Clean out
fuel tank and lines if Þlter contained sludge. Clean
out Þlter if full of wax or dirt.
3. Drain and reÞll tank. Drain fuel Þlter and bleed
injectors.
4. Replace Þlter if necessary. Remove and clean out
air cleaner body, intake duct, cap, hoses, and dust
unloader.
5. Check fuel ßow at pump and injectors. Supply
pump minimum pressure is 5 1/2 psi. Replace
worn, damaged, or failed parts.
6. Inspect and repair or replace lines, clamps as
needed.
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