I have an overheating fuel pump in the front trunk. I think it overheats because of the heat coming off the radiator and screws up the pump enough to so I loose fuel pressure down to 1psi.

The pump is a new holley red w/a holley regulator. The pump gets so hot you cannot keep you hand on it. I iced it down a bit and my pressure immediately comes back up. I considered the heat could be from the pump, but the wiper motors also get too hot to touch.

So where do you mount your pump (if not in the front trunk)?
Or what kind of pump do you have (if in the front trunk)?
..or maybe I have to cut more openings..?

I had mine under the fuel tank, and they go bad there too. Now, mine is in the front trunk, with some insulation over it. I mainly moved it so that it is easier to swap out when it goes bad.
For a while I had one in the engine compartment, but electric pumps are pushers, not pullers, so I was having some fuel starvation issues.

Mark

it will run cooler if you run it as a return system.

Sorry, what does that mean?

As original. One hose fuel-pump to motor. Return line fuel-pump to tank.

That makes sense.
You can add a tee fitting and add a restrictor on the return side so that fuel is conatantly flowing through

Mark

it takes a bypass regulator, fuel to the pump to the reg. then reg pressure to carb/fuel rail, then bypass port to return line to tank.

So I could put the T anywhere after the pump. (I would rather "T" in the front of the car than after to run a 2nd line from the engine to the tank.)
The restrictor is a separate in-line. There isn't one built into the return line fitting and on the bottom of the gas tank, right. And that will flow might be enough to cool the pump.

I think you need to address the excessive heat issue. I've had my pump under the tank for 20 years and the radiator's never created that much heat, especially to effect the wiper motors. Do you have a good hood seal? How do you exit the air?
Bruce
old V8 guy

My mistake, I meant to write the HEADLIGHT motors. The HEADLIGHT motors get hot, but they still work OK.

Just the fuel pump, which is mounted in the trunk (not under the tank) gets hot also, and loses pressure.

If the problem is the location, then the return line is not going to help. If the lack of return line is the problem, moving it is not going to help. So I'm seeking comments. Thanks.

My engine temp is stable at 180-190; I assume most V8 experience a lot of heat in the front trunk?
I exit the air thru the common fender openings.

My fuel pump is in the front, and I did have a recirculation line with restrictor, which I since abandoned. All seems to run cool under the hood, fuel pump, lights etc. I would address the air flow issue, make sure you are exiting 2x as much air out than is entering, this will help create a "low pressure" area and keep the air moving while driving. When in traffic make sure you have plenty of fans.
The only other issue which may cause a component to run hot is low voltage, as the voltage drops, the amps / watts goes up more heat is generated in the windings of the motor. Make sure the voltage is 14Vdc - 16vdc. Hope this helps here is a pict of my set up.

Also make sure the pump is mounted properly, my Carter is oil filled and needs to be motor end down. I think Holley is motor end up.

Click to view attachment

tony is most likely on to the issue with low voltage, then the pump gets hotter and draws more amps. run big wire to the pump 'bout 8 ga.

Thanks for the pix, Tony.

My pump is not located much different than yours. Your's doen't get really hot to touch??

Headlight motor and even, battery get hot.
My fender holes are not as large as yours. Maybe I'll open them up some more.

The car is NOT overheating, so I stopped cutting.

When I installed this holley, my pump felt very hot after running for a short time. Since my car is a 75 the wiring for the fuel pump was already there, so I used the stock wiring. I never tried installing a heavier gauge, which now I'm very curious if that was the root cause. The pump was so noisy I decided to pull it and replaced it with another pump that I had that worked great and was quiet.
Let us know what you find out.

Can one of you guys tell me why you don't use a SBC pump that is mounted on the block?? I thought it was due to the pump not fitting due to the engine mount and bar, but I find it hard to believe that is the case...

Am I wrong ???

I think Tony is right on with the wiring. As much air flow as there should be going thru your trunk it should not get to hot to touch. Especially if your car isn't overheating. Sounds like your air flow is fine Everything in your front trunk being so hot does seem weird too. So maybe there isn't the air flow needed? I'm stumped

Computer4kids - My pump is similar design to your's, except a holley red.
I measured voltage at the pump is 11.4v (Is that too low?) but off the alternator and at the battery is 12.1v. I may have to wire a direct circuit + relay to power the pump.

I will try a sheet metal box around the pump and insulation to protect it from the radiant heat. If it still get hot, maybe it's back to the pump? I thought about using a carter, like I have on my other car, or a mechanical pump (datkotaewing).

One last thing before you go too far. The 11.VDC is low but should be OK. 10% is a rule of thumb on any electric device, so 12-1.2 is 10.8v min. even then you have charging problems or regulator issues. Most regulators are designed for 14VDC.

So the Holley Pump has a plate on the pump end, I think I took one a part once to check the vanes or wipers. You should be able to disassemble it and check for unusual wear and play in the motor bushings. Worn bushings causes binding and the armature can get misaligned in the stator, again causing it to work harder and overheat. If it was AC you could use a AMP Probe to measure the current. being DC you will have to use an amp meter in line with the pump motor and verify the amp draw, unless you have a DC amp probe, If you don't know the rated Current, measure the resistance of the winding between + and - , then E ( Volts) / R (resistance) will give you the rated amps. then compare that to the actual measured amps. The measured Amps should be well below the rated amps, again the 10% rule but below the rated amps.

Try a spare pump it's easier and faster.

Tony

Thom
If your using a electric water pump you can use the stock SBC block mounted mechinacal fuel pump. Otherwise either the waterpump or alternator are in the way.

Bob

Here's the specs on your red holley. My holley was brand new out of the box and it got hot...I don't think it has anything to do with air flow. My guess would be now the wiring. PS If you wanted to have a return line for fuel, holley makes a nice pressure regulator with that extra port. Mount it in the engine bay and run a return line (unless you still have your stock line still there). I didn't think about meauring voltage when I had it apart. When I put on a smaller pump it ran perfectly cool...my bet is with the wiring. Need to measure amperage draw. Since it only is suppose to draw 2 amps (fused at 7), you should be able to put a meter in line like Tony said.
Tumble Polished Billet Look
New Lower Housing Casting for Enhanced Fuel Flow and Quieter Operation
Maximum Pressure Is 7 PSI
Motor Draws 2 Amps Current
7 1/2 Amp fuse recommended
Constant Fuel Flow with No Pulsation
Improved design for street/strip applications
Distinctive “RED” logo
Flows 97 GPH (free flow)
Flows 71 GPH at 4 PSI
Regulator is not required
Has externally accessible pressure relief valve (max 7 PSI)
Rotor/Vane pump design is more tolerant of contaminated fuels
Weighs only 2.88 lbs
Includes mounting bracket
Repair kits are readily available
Can be serviced from either pump end or brush cap end
NOT compatible with alcohol or methanol fuels
Use of safety shut-off switch, P/N 12-810, strongly recommended
Not designed or recommended for use with fuel injection systems

Thanks tony and computors4kids - I'll check the draw and see what where it's at. So if it's at 2amps, should be fine thru the wire I have (i think 16-18).

Yeah, the pump gets so hot, it's hard to believe they were designed to normally operate at that temp.

How about the fuel filter ? My pump and filter is in the engine bay, and gets hot as well. the fuel filter was rite up against the engine sheet metal, once moved , the problem was less frequent, but as of yesterday, it messed with me again, the car doesn't overheat , neither. I was told maybe I need bigger fuel lines ? It sounds like the fuel pump is starving, I have a Mallory 60.

Thanks Bob !!!

I have a Holley red on my SBC car. Mounted in the front for about 10 miles. Its was way too loud mounted there. I moved it to the rear and mounted it in rubber where the stock fuel filter was. You can not hear it run now. Been working great for over 15k miles.


Bob

For my 2c, I would agree that you shoud FIRST check out the pump to be sure there is not a problem with shorted windings that could create the heat.

Then, look at mounting the pump back in the engine bay as I did: I ran my fuel line down the right-side chassis box section and mounted the pump low on the right side. It has been working faithfully for 6 years.

While I throwing out cheap advice: take the header tank and catch bottle out of the trunk, plumb directly to the engine bay and mount the header tank as high as you can (above the engine) in the rear. I have a small header tank back on the right side of the engine, some 4-5 inches above the water outlet, but still fitting UNDER the engine cover. I filled the car with water and coolant, let the air AUTOMATICALLY extract the air from the system, filled to 1/2 full tank level and have not touched the water in several years! THIS is the right way to use a header tank as there is a 3/8" tube run from the thermostat housing to the top part of the header tank and this is how the AIR separates from the water. It is so easy!!

Best of luck,
Terry