SECTION 5
TROUBLESHOOTING
TROUBLE ANALYSIS FOR DETROIT DIESEL FUEL SYSTEM (CONT.).
TABLE 5-2
CORRECTIVE ACTION
PROBABLE CAUSE
TROUBLE
Replace the needle valve and tip
W orn or eroded needle valve or
L o w Needle Valve
assembly.
valve seat in tip.
Injector Opening
Pressure
Replace the needle valve and tip
W orn or damaged needle valve
assembly.
grill.
Replace the spring seat.
W orn or damaged needle valve
spring seat.
Replace the valve spring.
W orn or broken valve spring.
Disassemble the injector and
Dirt or foreign matter in injector.
clean the parts.
Remove carbon with tip reamer.
Carbon or foreign material on
High Needle Valve
spray tip.
injector Opening
Pressure
Clean orifice with the proper size
Carbon in tip orifice.
wire cleaner.
TABLE 5-3. TROUBLE ANALYSIS FOR ELECTRICAL SYSTEM.
CORRECTIVE ACTION
PROBABLE CAUSE
TROUBLE
STARTING
CIRCUIT
NOTE: For units not equipped with running lights, a sealed beam light can be made up for test
purposes. Attach one side of the filament to the battery terminal on the alternator and
ground the other side of the filament on the unit s chassis.
Recharge or replace battery.
Battery dead.
No Cranking, No
Lights
Clean and tighten connections.
O p e n circuit.
Replace wiring,
Clean battery terminals and cable
Poor connection, probably at the
No Cranking, Lights
ends.
battery terminals.
Go Out When Cranking
Is Attempted
Replace defective cables.
Defective cables.
Clean or replace defective parts.
Pinion not engaging with the
No Cranking, Lights
flywheel ring gear.
Dim Slightly When
Cranking Is Attempted
Clean commutator. Replace
Excessive resistonce or open in
brushes. Check and repair solenoid
cranking motor.
contacts. Repair poor connections.
5-42.
