Service manual
ENGINE
TROUBLESHOOTING
The following troubleshooting chart describes certain
problems relating
to
engine service,
the
probable causes
of
these problems, and the recommendations
to
overcome
these problems.This chart
may
be
of
assistance
in
determining the need for
an
engine overhaul.
PROBLEM
PROBABLE
CAUSE
HARD
STARTING
LOW
CRANKING
SPEED
1.
Engine
oil
viscosity
too
high.
2.
Run-down
battery.
3.
Worn
battery.
4.
Battery
terminals
loosely
connected.
5.
Defective
starter.
DEFECTIVE
INJECTION
SYSTEM
1.
Air
trapped
in
fuel
passage.
2.
Clogged
fuel
filter.
3.
Low
injection
pressure.
4.
Inadequate
spray.
5.
Injection
pump
delivering
insufficient
fuel.
6.
Injection
too
early.
MAIN
ENGINE
TROUBLES
1.
Low
compression.
a.
Incorrect
valve
clearance.
b.
Inadequate
contact
of
valve
seat.
c.
Valve
stem
seized.
d.
Broken
valve
spring.
NOTE:
The
engine's electrical system is protected by a
20-
ampere manual reset circuit
breaker.
The
preheat solenoid
is
mounted on
the
same
bracket.
VERIFICATION/REMEDY
1.
Replace
engine
oil
with
less
viscous
oil.
2.
Recharge
battery.
3.
Replace
battery.
4.
Clean
terminals
and
correct
cables.
5.
Repair
or
replace
starter.
1.
Bleed
air
from
fuel
system.
2.
Clean
or
replace
filter.
3.
Adjust injection
pressure.
4.
Clean
or
replace
nozzle.
5.
Repair
or
replace
injection
pump.
6.
Adjust injection
timing.
a.
Adjust
valve
clearance.
b.
Lap
valve.
c.
Replace
valve
and
valve
guide.
d.
Replace
valve
spring.
e.
Compression
leaks
through
cylinder
head
gasket.
e.
Replace
gasket.
/.
Piston
ring
seized.
/.
Replace
piston
and
piston
ring.
g.
Worn
piston
ring
and
cylinder.
g.
Overhaul
engine.
2.
Burnt
glow
plug.
2.
Replace
glow
plug.
3.
Faulty
glow
plug
operation.
3.
Correct
lead
wire
connection,
check
preheat
solenoid.
4.
Incorrect
governor
lever
position.
4.
Set
lever
to
starting
position.
LOW
OUTPUT
LOW
COMPRESSION
See
HARD
STARTING
INJECTION
SYSTEM
OUT
OF
ADJUSTMENT
1.
Incorrect
injection
timing.
1.
Adjust injection
timing.
2.
Insufficient
injection.
2.
Repair
or
replace
injection
pump.
3.
Low
injection
pressure.
3.
Check
injection
nozzle
and
adjust
pressure.
INSUFFICIENT
FUEL
1.
Air
trapped
in
fuel
system.
1.
Check
and
retighten
connector.
2.
Clogged
filter.
2.
Clean
or
replace
filter.
3.
Contaminated
fuel
tank.
3.
Clean
tank.
INSUFFICIENT
INTAKE
AIR
1.
Clogged
air
intake
silencer.
1.
Clean
or
replace
air
cleaner.
(continued)
Engines
&
Generators
3