How to Test, Remove and Install a Corvair Fuel Pump
HOW TO CHECK YOUR FUEL PUMP
Although I have never had any problems with a fuel pump going out, others have. There are no real symptoms except if you press on the accelerator while moving and experience no acceleration, sputtering of sorts. Sometimes they give no warning and just stop leaving you high and drive or leak.
Assuming your car has gas in the tank and clear fuel lines, you can check for its operation:
1. Disconnect the fuel lines at the carburetors.
2. Disconnect the primary coil wire from the coil so engine does not start but turns over.
3. Place containers at end of fuel lines.
4. Turn ignition key on. Do not use a remote starter.
5.A good pump will produce 1 pint of fuel in 40 seconds. Using a fuel pressure gauge, attach it to the end of the fuel line disconnected from the carb. Run engine and idle speed, Pressure should read 4-5 lbs. If too high or low or fluctuates, pump is going bad. Replace.
REMOVING THE FUEL PUMP
1. Engine OFF Preferably Cool
2. Using TWO Tubing Wrenches if possible, remove fuel lines at 3 places on pump (the inlet, two outlet lines at the T connector. Leave the T connector and pipe in pump/
3. Below and to the rear of pump, loosen 9/16" locknut on 1/2" headed jamb bolt.
4. With finger, loosen bolt until fuel pump will pop / pull UP and out. Carefully remove the push rod from engine.
The DIMPLE or indentation on lower portion of pump stem\shaft must have a rubber O-Ring.
5. Remove 1/8" brass pipe from pump.
6. Remove 3/8" Female Flare Fitting
INSTALLING A FUEL PUMP
Note: No sealer /tape is needed with brass fittings.
LOOKING FROM TOP OF PUMP
1. Insert and tighten 1/8" brass pipe in RIGHT side hole.
2. Insert Brass Flare fitting in LEFT side hole.
3. Make sure O-ring is installed on new pump/ grease lightly.
4. Set Pump in hole with brass Pipe pointing straight towards the front of the car
[forward]. With fingers, turn 1/2" Bolt IN, while wiggling pump to find DIMPLE!
Only tighten Finger TIGHT! But Snug!
5. Using a wrench, hold Bolt head rigid!, make it a snug nut fit. Pump should still wiggle slightly in hole.
6. Insert and USING FINGERS ONLY, thread and tighten Flare nuts on 3 fuel lines taken off.
Using Tubing wrenches if possible, tighten [ SNUG ONLY] three fuel lines.
7. Using a screwdriver, tighten screws on top of pump by SNUGGING each one as you move in a circle, as many times as it takes to not find any of the screws loosened, since you last tightened them.
8. Start Engine and check for leaks.
CHECKING YOUR FUEL PUMP REPLACEMENT
Because of poor quality control in manufacturing, one should check certain things before installation.
1. Take a photo or note how the fuel pump is assembled, as once it is apart, you may have confusion when putting it back together.
2. Disassemble the fuel pump by removing the five screws. Always pay attention of how things are as you take it apart.
3. Remove the spring.
4. Make sure there is an anti-backflow dam. This is usually on the shaft and above the base of the pump. It prevents gas getting into the oil.
5. Holding the stem\diaphragm in one hand, see if you can rotate the top one against the lower one. If you can, return it. They should NOT rotate against one another. Make sure all diaphragms are reinforced fiber as the lower one is usually the one that fails.
6. Carefully reassemble the pump and do not over tighten the top 5 screws to where the