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Fuel Pump Stuttering and Dying

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Old 08-20-17, 03:19 PM
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Fuel Pump Stuttering and Dying

Hey guys,

About 700km ago, I installed a holley red fuel pump to go with my rebuilt 12a and holley carb (from racingbeat). At this time I also changed the fuel filter and installed a fuel pressure gauge. The pump is electric and super loud, so I can tell when it's working! I've had no issues until now.

Three days ago I was on a freeway going about 90kph when I heard the pump sputter and quit. I pulled over as the car died and spent about a half hr on the side of the road. Eventually I turned off the cabin fan and the pump came back on, and I managed to get home. The fuel pump sounded like it was struggling, and my fuel pressure was bouncing in sharp spikes between 3 and 6 psi.

Then two days ago I was running errands and came back to the car after about an hour, and the pump was totally dead. I had to get it towed home.

What I've tried:
- checked the plugin for the pump and it registers a steady 12.4V
-checked fuel lines for leaks/kinks/damage and found nothing
- re-soldered the stock plug to the fuel pump, thinking it was a faulty connection. The pump starts now but my fuel pressure is still all over the place and sounds like it's really fighting to move.

Before I buy a new fuel pump, could it be something other than a faulty pump?

Thanks

Roland

Last edited by UnregisteredSA22C; 08-20-17 at 03:44 PM. Reason: Forgot to add something
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Old 08-20-17, 07:23 PM
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Was the pump new,what did the old fuel filter look like,what does the one in the car now look like?Was/is filter in of front of pump or after pump. If after pump is it possible junk/trash from gas tank has gotten into pump? Connect voltmeter into pump circuit and run/drive car while its acting up and observe voltage. Should be steady/not erratic,about 13.5 volts with car running.
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Old 08-20-17, 07:51 PM
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Are you running your fuel dead headed or do you have a return line hooked up?

How long did you have the car running prior to the Holley swap? So can we rule out bad fuel tank gunk.



EDIT: test your pump before you buy a new one. Just plug it into a 12VDC source and run some water through it. (don't run it dry)
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Old 08-20-17, 10:49 PM
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Thanks for the answers! I'll try testing the pump using a different power source, and have a look at the voltage as I drive.

I bought the pump new, and the filter is installed before the pump. I don't have a return line. Prior to the Holley install it wasn't running at all (sat for about 15 years). When I fixed it up I didn't remove the tank but I did pump out as much of the old gas as I could.

Roland
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Old 09-17-17, 12:10 AM
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Thanks for the help everyone. I got a carter fuel pump and installed it and everything's been running great! The carter is a lot quieter than the holley too.
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