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Mechanical Diagnosis
160
Engine does not develop full
power
Air intake system clogged
Clean air intake system
Fuel tank vent clogged
Unclog vent
Clogged fuel tank or fuel lines
Clean fuel tank and fuel lines
Insufficient fuel volume leaving filter
Check for dirty filter or air in system
Air cleaner clogged
Replace air filter
Delivery of electric fuel pump
insufficient
Repair pump
Injection pump timing off
Adjusting timing
Injection nozzles defective
Repair or replace nozzles
Worn injection pump plungers,
delivery valve defective, injection
rate too low, gum formations
Repair or replace pump
Compression low or unbalanced
Overhaul engine
Engine speed too high
Misadjusted high speed solenoid
Adjust high speed solenoid linkage
and check high speed stop screw
Defective injection pump
Repair injection pump
Engine fails to stop when unit is
OFF
Fuel solenoid defective
Replace
Injection pump defective
Replace pump
Engine knocks heavily
Air in system
Bleed fuel system
Wrong fuel
Change fuel
Injection pump not timed
Retime injection pump
Injection nozzles fouled or opening
pressure too low
Clean, repair or replace injection
nozzles
Delivery valve spring broken
Replace spring or repair injection
pump
Compression too low
Overhaul engine
Valve out of adjustment
Adjust valves
Fuel return line plugged
Remove return line restriction
Rod or main bearing worn
Replace rod or main bearings
Engine runs hot
Dirty radiator
Wash radiator
Coolant level is low
Add coolant
Cooling system heavily scaled
Cleaning cooling system
Cylinder head gasket leaks
Replace cylinder head gasket. Use
correct gasket
Faulty thermostat
Check or replace thermostat
Loose or worn water pump belt
Replace belt
Condition
Possible Cause
Remedy