Fuel Pressure: Testing and Inspection

Fuel Pump Diagnosis

Fuel Pump Pressure Test

1. Disconnect fuel line at carburetor and connect a suitable pressure gage (such as Pressure-Leakdown Tester J-22109 or equivalent).

2. Start the engine and run at slow idle speed.

3. If pump pressure is below 31 kPa (4-1/2 P.S.I.), the pump should be replaced.


Fuel Pump Flow Test

1. Disconnect fuel line from carburetor. Run fuel line into a suitable measuring container.

2. While observing the sweep second hand of a clock or watch, run the engine at idle until there is one pint of fuel in the container. One pint should be pumped in 30 seconds or less.