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Reference Section--Electric Pump Troubleshooting

Troubleshooting Guide

PROBLEM
Insufficient fuel delivery.
CAUSE
Clogged pump filter screen or clogged strainer in tank.
Break or restriction in fuel line (pinched or kinked line.)
Incorrect float lever, malfunctioning inlet needle or clogged inlet screen in carburetor.
Return line.
Vapor trapped in fuel.
Loose fitting or air leak on inlet side of fuel pump, or broken fuel line.
Wrong pump for application.
Plugged gas-cap or fuel-tank vent.
Low gas level in gas tank.
REMEDY
Clean or replace filter.
Repair fuel line or remove restriction.
Repair or replace as needed.
Reduce orifice in return line, or plug.
See vapor lock remedy.
Tighten and clean all connections at the pump.
Check fuel line and replace bad line.
May need larger output pump.
Clean gas cap or tank vent.
Add gas to tank.
PROBLEM
Pump not operating.
CAUSE
Damaged or improper wiring.
Loss of ground.
Blown fuse.
REMEDY
Inspect mounting and all wiring as outlined in instruction sheet.
Clean frame or metal surface to which pump is mounted.
Tighten mounting bolts.
Replace fuse (5 amp).
PROBLEM
Carburetor flooding.
CAUSE
Worn needle and seat assembly in carburetor.
Too much pressure due to wrong model fuel pump:
1) Standard pressure;
2) Low pressure.
Air leak on inlet side of pump due to hole in fuel line or loose fitting.
Increased pressure due to fuel vapor.
REMEDY
Replace worn needle and seat assembly in carburetor.
Check with auto dealer on pressure that carburetor will hold.
Tighten all fuel-line connections at pump and other connections which were opened during pump installation.
See vapor lock remedy.
PROBLEM
Fuel pump leaks.
CAUSE
Fuel-line fitting loose at pump.
Fuel line to fitting loose.
REMEDY
Tighten all fuel line connections at pump and all other connections which were opened during pump installation.
PROBLEM
Pump has loud, fast pounding noise; does not shut off.
CAUSE
Pump is pumping air due to air leak on inlet side of pump:
1) Broken fuel line;
2) Loose fitting on inlet side;
3) Loose hose to fitting on inlet side.
REMEDY
Check for hoses or cracks in fuel lines; check and tighten all fuel-line connections between tank and pump.
PROBLEM
Vapor lock.
CAUSE
Pump "sees" vapor.
Pump mounted on high-heat area.
Plugged or partly plugged inlet fuel line causing fuel to be placed under high vacuum.
Pump location and fuel-line routing.
Plugged gas-tank or gas-cap vent.
Poor fuel.
REMEDY
See vapor lock remedy.
Remount pump in cooler area.
Clean filter before pump; check for clogged fuel line, pinched or kinked lines.
Mount pump with outlet above horizontal.
Clean vent hole.
Try different type of gasoline.

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