electric fuel pump problem? Thats a maybe.

rubicon · Sep 28, 2024

Indycars said:
Check the voltage at the pump. Flow volume drops drastically with a reduced voltage.

Are you using a relay with a switch or a switch only to provide voltage to the pump?

Thanks good info. Will check it tomorrow.

LongJohn · Sep 29, 2024

I think you have found his problem Rick.

fletcherson · Oct 14, 2024

I have two of those Holley pumps. A red one on the rear tank on my dually, and a blue marine version on my cuddly cabin. I’ve had trouble with both of them. The one in my truck acts similar to what yours is doing. I haven’t diagnosed it yet, I’ll likely just ditch it. The one in my boat was brand new and locked up after sitting over the winter. When I disassembled it, it looked like it had been in a lake for years. All corroded up. The ethanol destroys them, they do not stand up to it well. I do think parts are available to service them. When the one on my truck acts up, I can tap on it and it will usually run. I suspect it has internal corrosion like the marine one did.

Indycars · Oct 15, 2024

fletcherson said:
I do think parts are available to service them.

I had a electric fuel pump failure in August 2021 and I couldn't find any replacement parts then. Quickfuel sells an end bell that looks like it should work but will not. For more info check out my thread on this situation.

Electric Fuel Pump Failure

I had a fuel pump failure yesterday. I was on my way to Advanced Auto where I did work to recycle some oil when it failed. First I tested by connecting power directly to the pump, all I got was sparks when I made the connection. Pump did not turn over. I pulled it apart to see what went wrong...

tbucketeer.com

.

rbsWELDER · Oct 15, 2024

I have had several Holley fuel pump failures. I moved to a K&N from Advanced Auto, with a lifetime warranty and have not had a problem!

Indycars · Oct 15, 2024

rbsWELDER said:
I have had several Holley fuel pump failures. I moved to a K&N from Advanced Auto, with a lifetime warranty and have not had a problem!

Not trying to talk down or criticize your choice rbsWelder. Just didn't want others to think that would work for everyone.

Using the pump below as an example

That would not flow enough for any engines over a couple hundred horsepower. The pump flow rate 38 gph and that's free flow, it's not pumping against any pressure.

Edelbrock Universal Micro Electric Fuel Pump - 38 GPH / 144 LPH (Gasoline/E85)

Advance Auto Parts - Down for Maintenance

shop.advanceautoparts.com

Fuel flow at a pressure of 5 psi will cut the free flow rate more than 1/2. The Holley pump below is rated at 97 GPH, but at 5 psi its only flowing 44 gph. Therefore the flow rate of the Advance Auto pump would be 17 GPH.

Below is the Holley pump and it's flow at different pressures.