Main Fuel Pump Testing

1. Ensure that there is free flow through fuel filter and associated lines.
2. Ensure that voltage supply is normal.
3. Remove fuel pump relay from position 2 on fuse/relay panel, then install remote control jumper US 4480/3 in its place. Ensure that remote control switch is OFF.
4. Remove fuel filler cap, then detach fuel return line at connection and place open end into a suitable measuring container. Use an extension hose if necessary and ensure that measuring container has a capacity of at least one liter.
5. Activate remote control for 30 seconds and measure amount of fuel delivered.
With the engine OFF, pump ON, the amount of fuel delivered should be:
760 ml @ 12 volts
600 ml @ 11 volts
460 ml @ 10 volts
330 ml @ 9 volts
6. If fuel delivery rate is not as specified, first check fuel filter for blockage and replace as necessary.
7. If delivery rate is still insufficient, check for pinched or clogged fuel lines.
8. If fuel filter checks out as unrestricted, replace fuel pump and recheck delivery rate.