Thread: Electric Fuel Pump

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We just got our 32 coupe running and have been doing shake down runs. I put a fuel cell in the trunk and a Summit electric fuel pump with pressure regulator, relay and circuit breaker. I have at least 3 inches of plywood, foam, sound deading, and insulation between the trunk and the cab.

It sounds like I am making home made ice cream and after running the fuel pump is almost too hot to hold you hand on.

Is this normal?????????????

Did you insulate the fuel pump from the frame with some rubber pads? If not, it will sound like a food processor. They do run pretty hot. Which Summit pump do you have, and what pressure are you trying to run?

I think Summit pumps are Holley clones. Holley pumps sound like they are grinding walnuts . . . or pea gravel. My brand new Holley red pump didn't make it past the first week. It got hot and went out on thermal overload. It left me stranded twice. I threw it in the trash and got an Edelbrock. It's much quieter.

If you can hear your fuel pump, maybe your mufflers are too quiet.

I have Stewart Warner fuel pumps in both of my cars and both are relatively quiet when run and I don't notice any abnormal heat. The one in the 57, makea a clicking sound when it is pushing gas to the carbs, but once the carbs/lines are loaded it's whisper quiet. The one in the 34 doesn't click when loading, but it is a little noiser, probably due to location. The 57's is located between the gas tank and the rear bumper and the 34's is located on the frame near the rear wheel (a lot closer).

Could be the Smithy's don't let the fuel pump's sound get noticed.

I have a new spare unit and would like to find a couple more, since I don't see them advertised anymore for 12 volt systems. I have seen them for 6 volt systems.

Originally Posted by Henry Rifle

Did you insulate the fuel pump from the frame with some rubber pads? If not, it will sound like a food processor. They do run pretty hot. Which Summit pump do you have, and what pressure are you trying to run?

I think Summit pumps are Holley clones. Holley pumps sound like they are grinding walnuts . . . or pea gravel. My brand new Holley red pump didn't make it past the first week. It got hot and went out on thermal overload. It left me stranded twice. I threw it in the trash and got an Edelbrock. It's much quieter.

If you can hear your fuel pump, maybe your mufflers are too quiet.

The pump is not rubber mounted I may try that. The summit pump looks just like a Holley and who knows may be made by Holley. If I can't get it quietend down I may change to Eldebrock. The only thing I have this in the trunk with all stainless lines and I sure would hate to have to do over that.

Originally Posted by mopar34

I have a new spare unit and would like to find a couple more, since I don't see them advertised anymore for 12 volt systems. I have seen them for 6 volt systems.

Mopar

Here's a link to the SW website. Summit lists the pumps.

http://www.sw-performance.com/products/ACCFuelPump

http://store.summitracing.com/egnsea...alse&N=700+115

Sorry for the hijack.

Mike

I was able to mount the Edelbrock directly to my existing lines. If I remember correctly, it bolted right up. All I had to do was drill some extra holes in the frame. The mounting bracket was a little different.

For some reason, some Holley or Summit pumps will be noisier than others. I had one in my Jeep that sounded like you describe..........people riding with me would ask " what is that compressor running?" At redlights I would see other drivers looking to see where the noise was coming from. Yet I have the same model in my '27 and in my current T, and they are much quieter. In fact, I have to listen carefully to make sure my electric pump is running before I fire up the engine in my '23. My Son has a Summit pump in his T and it is also quiet. Don't know why some are worse than others, but it happens.

Rubber mounting does help, but the one in my Jeep had two thicknesses of rubber pads under it and the thing still rattled away.

Don

I've always used some sort of exhaust pipe rubber hanger to mount electric pumps. It isolates the noise from the car pretty well. I did a search for a pic, but couldn't come up with the ones I used to buy (Pep Boys). Here's an example of what I'm talking about.....
http://www.automedia.com/Exhaust_Han...es20020401eh/1
These are not exactly the ones I've used, but should be better than solid mounting or rubber pads between the pump and mount point.

The other thing is, it sounds like you have the lines routed deadhead. The pump may run cooler and quieter if you run a return line with a regulator to set pressure at the carb inlet to around 5 1/2 lbs.

Here's a cute little exhaust insulator I found at Jegs that might work well and look sanitary also......
http://www.jegs.com/webapp/wcs/store...-1&showValue=1

Thanks Mike.

I am using a GM pump part number 25115899 that pumps 72 gallons per hour at 6-8 psi outlet pressure. It comes with a rubber insulated mount and is still loud.

If you do not run a return line to the tank, a Holley pump will run hot and puke out on you. Mine lasted one year and left me stranded 30 miles from home. I replaced it with a Mallory unit which has no outlet for a return line, and it has served me well for over a year. It has a different internal design than the Holley units.

The Mallory pumps are Gerotor type. The Holley blue, red, and blacks series are rotary vane type pumps. Gerotor pumps are much more rugged than RV pumps and also have superior suction qualities over RV pumps in general. And, surprise surprise, the Gerotor pumps are more expensive. Holley also makes Gerotor pumps and they are slightly less expensive than Mallory pumps according to what I've seen on Summit.

My suggestion for purchasing electric pumps;

1) Buy a Gerotor style pump
2) Use an oil pressure cut off switch with it if possible
3) Don't use too much pump. For gasoline, natural aspiration you need 8-9 GPH per 100 hp.
4) For max perfromance and cool factor buy a pump with 12-14 psi and use a bypass style regulator with return line. This will make it very hard for you to overheat the pump or experience vapor lock.
5) Use 15-30 mic screen before pump and 10 mic filter after pump.
6) Use minimum 3/8 line suction and supply/return. Avoid 90 degree elbows close to carb, curved tubing or hose better
7) Mount pump using 3/16 rubber pad to frame
8) Use a relay switch with the pump. You may also want to use a hidden toggle for added theft prevention

I think that gets most of it ...................

Kitz

You nailed it, Kitz!

What is the voltage at the pump terminals?

Most times electric fuel pumps end up at the end of a long line and low voltage makes them run hot and burn up pretty fast.

It's not uncommon to see a 2 volt difference between voltage at the battery and at the pump.

Use a continuous duty relay, feed the relay with 10 gage wire and control the relay with the long run of wire from the ignition switch or wherever your source wire terminates.
14 gage is a good size for this wire.

If the relay is close to the pump, you'll have voltage within a few hundredths of battery voltage.

I've got a Carter electric pump feeding a carb and its quiet.