Troubleshooting

50 RENR2696-01
Troubleshooting Section
•
Seizure
•
Broken components
•
Bent component
s
i01798127
Excessive B lack Smoke
Probable Causes
•
Air intake sys
tem or exhaust system
•
Individual malfunctioning cylinder
•
Valve lash
•
Low compressi
on (cylinder pressure)
•
Fuel injection nozzles
•
Turbocharger (if equipped)
•
Broken 5 volt
supply wire to the pressure sensor in
theintakemanifold
•
ECM software
Recommended
Actions
Air Intake System or Exhaust System
1. Check the air filter restriction indicator, if equipped.
2. Ensure that t
he air filter is clean and serviceable.
3. Check the air intake and the exhaust system for
the followin
gdefects:
•
Blockages
•
Restrictions
•
Damage to the
air intake and exhaust lines and
hoses
4. Make all nec
essary repairs to the engine.
5. If the problem has not been eliminated, proceed
to “Individ
ual Malfunctioning Cylinder”.
Individual Malfunctioning Cylinder
1. With the engine speed at a fast idle, loosen the
high pressure fuel line to the fuel injection nozzle
of number 1 cyl
inder. Note if there is any reduction
in engine speed. Tighten the high pressure fuel
line to the fuel injection nozzle.
2. Individually repeat this procedure for each fuel
injectionnozzle.Ifthereisnoreductioninthe
engine speed
proceed to “Checking the Fuel
Injection Nozzles”.
3. If there is a r
eduction in engine speed proceed to
“Valve Lash”.
Valve Lash
Ensure that the valve lash is correct. Reset the valve
lash if it is n
ot correct. Refer to Testing and Adjusting,
“Engine Valve Lash - Inspect/Adjust”.
If the repai
r does not eliminate the fault proceed to
“Low Compression (cylinder pressure)”.
Low Compres
sion ( cylinder pressure)
Examples of low compression are shown in the
following l
ist:
•
Mechanical problem
•
Faulty piston rings
•
Worn cylind
er bores
•
Worn valves
•
Faulty cylinder head gasket
•
Damaged cyl
inder head
1. Remove the fuel injection nozzles and perform a
compressi
on test. Refer to Systems Operation,
Testing and Adjusting, “Compression - Test ”data.
2. Make all ne
cessary repairs to the engine.
3. Ensure that the repairs have eliminated the faults.
4. If the repair does not eliminate the fault proceed to
“Checking the Fuel Injection Nozzles”.
Checking the Fuel Injection Nozzles
1. Remove the
fuel injection nozzles from the cylinder
head. Refer to Disassembly and Assembly, “Fuel
Injection Nozzle - Remove”.