Thread: Loud Holly fuel pump!??

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I was wondering if anyone else has a problem with the "blue" electric holly fuel pump making a lot of noise? Its mounted thru a rubber pad on a rear cross member of my 37,but still transmits a LOT of the pumping noise.

I wanted to change to the holly mechanical unit, but the frame is pretty close. Does anyone make a high volume electric pump that doesnt make so much noise? OR , any way to mount this one so its quieter? Thanks!

I KNOW !!! My red one on my truck sounds like an air compressor, and I never noticed the one on my '27, probably because the exhaust is so loud.

I mounted both on rubber, but still loud. Someone on here posted a while back that you cut up the rubber straps that come on muffler hangers and use them as isolators, and I am going to try that. But I'm not sure if it is vibrations or just internal noise, because my truck is getting louder all the time.

But the upside is, at traffic lights it makes the guy next to you think twice.

Don

Do you have hard piping to the fuel pump? If so, a short length of braided rubber line on both sides of the pump will isolate the vibration and noise from the fuel line.

Henry R,
The cars got 1/2" hard line to a regulator on the firewall. But the pump already has short lengths of rubber fuel line on both sides to isolate it from the lines. I even thought about just "hanging" the pump loose temporarily,just to see if that helps.... BTW the pump does have a Fram canister filter hard plumbed to the inlet side. But the filter has a pc of rubber fuel line seperating it from the tank line.

Don, my pump has rubber from an exhaust hanger under it right now. I think part of the problem stems from the bolts holding it in place..

Right now I could probably get by with a smaller pump...this motors a pussy cat, but next year Im planning on a couple of things , starting with a set of aluminum,(maybe Vortex heads)? I want to get the car back into low 13/high 12s. soooo...... not sure where to go from here?

Don, my pump has rubber from an exhaust hanger under it right now. I think part of the problem stems from the bolts holding it in place..

Mine also has only neoprene fuel hose, which leads me to believe these pumps are just noisy in of themselves. I have a new one in the box that I'm saving for the '39, and have been tempted to try it on my daily driver truck, to see if it is any quieter, but I don't want to get gas in it yet.

Like I said, mine is getting louder all the time, and whenever someone rides in my truck, the first question is always "what is that noise?" I usually drive alone, so I just turn up the stereo.

You could be on the right track with the bolts transmitting the sound to the frame. Maybe a double insulated arrangement where the pump bolts first go to a rubber mounted bracket?

I don't know what the fix is, but loud pipes do help.


Don

I have the same problem, Im going to buy that new holley (black one) when i tear my car down for paint. Its suppose to be a lot quiter.

Originally Posted by Uptown83

holley (black one) . Its suppose to be a lot quiter.

it is i have one! very quiet compared to the blue that i had on

have used the blues there are not loud over the 4inch ex if you run with a flex hose on the inlet and outlet .used some rubber mounts . this type with a stud on one side and a threads for a bolt on the other side. i think they use them on harley oil tanks this is how i mount them and they are still a bit loud

I've found that the majority of street cars work just fine with a high performance, like Carter or Edelbrock, mechanical pump....

Originally Posted by Dave Severson

I've found that the majority of street cars work just fine with a high performance, like Carter or Edelbrock, mechanical pump....

yes this is ok if you have the pump rod.

yup.... Don't suppose that Donovan block even comes with one, huh??? I also like the belt driven pumps... anything is better then them rattling electric things!!! The only belong on cars with open headers so ya can't hear the flipping pump clattering away!!!!!

Originally Posted by Dave Severson

yup.... Don't suppose that Donovan block even comes with one, huh??? I also like the belt driven pumps... anything is better then them rattling electric things!!! The only belong on cars with open headers so ya can't hear the flipping pump clattering away!!!!!

oh yes it has a spot for one but alot of the new blocks do not

Originally Posted by Dave Severson

I've found that the majority of street cars work just fine with a high performance, like Carter or Edelbrock, mechanical pump....

Dave ,
I actually bought a new Holly mechanical pump, (#327...110gph )but it almost hits the frame rail without even starting the car. Im worried that with engine torque, it could hit... also need to see if I can "re-clock" the fuel inlet and outlet, they will hit for sure...

As for exhaust, the car has a nice throaty sound , but the fuel pump still dominates that noise competition.... might be worth a call to holley to see what they say?

they will not say much they are noisy. every car that i put them on were noisy. that is the way there are