Engine Driven Fuel Pump - Field Test procedure
Bulletin 84-6C-3Date Dec. '83
Ref. No. 84-039-6C
SUBJECT: FIELD TEST PROCEDURE ENGINE DRIVEN FUEL PUMP
MODELS AFFECTED: ALL WITH ENGINE DRIVEN LARGE DIAMETER FUEL PUMPS
Models with fuel return lines;
A. Engine at normal operating temperatures
B. Disconnect fuel hose from fuel tank to pump at the pump.
C. Connect known good vacuum gauge to fuel pump suction pipe.
D. Crank engine for 10 seconds, vacuum gauge should read 15" vacuum and hold there for at least 15 seconds.
If pump does not pass this test, replace pump.
Models without fuel return lines;
A. Engine at operating temperatures.
B. Disconnect fuel hose from fuel tank to pump at the pump.
C. Connect known good vacuum gauge to fuel pump suction pipe.
D. Crank engine for 10 seconds, vacuum gauge should read 12" vacuum but due to design will not hold this reading.
If this 12" reading is not obtained during cranking for 10 seconds replace pump.