ELECTRIC FUEL PUMP FAULTS
INSUFFICIENT FUEL
- Air leak at intake side of pump
- Air leak at diaphragm flange
- Leaking valves
- Perforated or faulty diaphragm
- Vapor lock in fuel line
- Faulty electrical feed
- Bad ground
- Contact points burnt
- Corroded throw-over mechanism
- Incorrectly adjusted throw-over mechanism
- Excessive diaphragm tension
- Blocked filter
PUMP BEATS RAPIDLY
- Carburetor flooding
- Air leak in suction line
- Fuel leak
- Vapor lock in fuel line
EXCESSIVE DELIVERY PRESSURE
- Incorrect pump fitted
DOES NOT OPERATE
- No electrical supply
- Bad ground
- Faulty coil winding
- Faulty internal pump connection
- Dirty contact points
- Corroded or incorrectly adjusted throw-over mechanism
- Diaphragm pressure excessive
MECHANICAL FUEL PUMP FAULTS
INSUFFICIENT FUEL
- Air leak at filter bowl or suction side of pump
- Air leak at diaphragm flange
- Leaking valves
- Blocked vent in gas tank
- Perforated or hardened diaphragm
- Worn or broken pump linkage
- Blocked filter
- Vapor lock in fuel line
EXCESSIVE DELIVERY PRESSURE
- Carburetor needle valve seating improperly
- Incorrect needle valve
- Diaphragm faulty
- Incorrect diaphragm spring
- Pump mounting gasket too thin