Possible Cause

Possible Remedy

Improper fuel (gasoline) in tank

Drain tank, flush system, fill with proper fuel

Tank empty or tank vent blocked

Fill tank/bleed system, check tank vent

Fuel filter blocked

Replace fuel filter

Injection lines blocked or restricted

Drill to nominal I.D. or replace

Fuel-supply lines blocked-resticted

Test all fuel supply lines - flush or replace

Loose connections, injection lines leak or broken

Tighten the connection, eliminate the leak

Pump-to-engine timing incorrect

Readjust timing

Injection nozzle defective

Replace or repair

Engine air filter blocked

Replace air filter element

Injection sequence does not correspond to firing order

Install fuel injection lines in the correct order

Maximum speed misadjusted

Readjust maximum speed screw

Overflow fitting interchanged with inlet fitting

Install fittings in their proper positions

Low or uneven engine compression

Repair as necessary

Fuel injection pump defective or cannot be adjusted

Remove pump and service