Fuel Pump Recommendations, Please

[Chris Kouba]

I have an issue with my pumps whereby I've ended up burning them up. I have two bladders in the sponsons which feed a swirl pot (currently) via a pair of Carter low pressure (3-5psi) pumps. There are returns to each sponson from the swirl pot.

The EFI system (Edelbrock Pro-Flow) runs fine with the supplied pump when the swirl pot is full. Pump runs 90psi to the rails and has a return line to the swirl pot.

The entire system has worked faultlessly while the car has been stationary.

My issue- there are no baffles in the bladders, only foam, allowing fuel to slosh forward under braking when the levels start getting low. On a normal car, I would shut off the pump of the empty-ish tank and start using the other but the heavenly noise out the exhaust drowns out anything the dying little pump could hope to emit. I haven't been sensitive enough to detect when the damage starts but once the swirl tank starts to get low enough, I'll get a stutter when I give it the boot after hard cornering/braking.

To rectify in the future, I could make sure the sponson tanks never get below a certain level. This seems a little over-reactive to me but something I will definitely be sensitive to in the future. Specifically this time, I took a shot at figuring out my mileage and ran one tank (8 gal) down to what I thought was empty, and that's when I burned it up.

What I would really like though is to be able to run a pump which has a bit of tolerance to being run without fuel to cool it. Can anyone recommend something? I certainly can't be the only person who has had to deal with this. I have yet to hear of an electric pump which fits the bill though.

The Carter pumps currently on the car are solenoid pumps. I have read on the internet that vane pumps may be more sensitive to dry running and that gerotor pumps might be "better". Does anyone have any empirical data one way or the other?

Any constructive suggestions are appreciated. Thanks in advance.

Chris

 

[Cliff Beer]

Chris, it sounds a bit silly but one of the smartest low-tech ideas I've seen for this problem (fuel starvation under g-loads) consisted of a rock....a rock stuck to the end of a flexible pick up tube in the tank. As the car accelerates/decellerates/turns, the rock moves in the direction of the accumulated fuel and helps to maintain flow. It actually works well.

Just a thought which may be worth considering.

 

[Chris Kouba]

Interesting, but won't work for me for two reasons: 1 - foam in the bladder already which won't the the rock roll & 2 - fuel pick up is a hard pipe rigidly attached to a bulkhead fitting which bolts into a fixture embedded in the bladder.

Just need a pump which can tolerate a little more air than normal.

 

[Robert May Eng.]

Interesting, but won't work for me for two reasons: 1 - foam in the bladder already which won't the the rock roll & 2 - fuel pick up is a hard pipe rigidly attached to a bulkhead fitting which bolts into a fixture embedded in the bladder.

Just need a pump which can tolerate a little more air than normal.

The facet red top is a favorite with the rally cars. No seals or gears, just a plunger. I dont know if you get them your side of the pond . They prime well between gulps of air.

AN -8 (JIC -8) Facet Works Red Top Fuel Pump Ideal for Swirl Pot Lift Pump on eBay!

Bob

 

[David]

I should think you do get them over there.

Big label on the box saying "Engineered and Manufactured in the USA" (I got through one this morning so it's sat on my desk!)

 

[Bill Musarra]

Chris,
The only way you are going to solve your problem is to add a sump of some sort to the tanks. You need to get the fuel to pool around the pickup. If you don't have access to the interior of the bladders then you will have to use a low pressure pump for carbs. to 1. get fuel to a sump or to a swirl pot, or 2. to survive the periods of air to the pump. Only the low pressure pumps can tolerate the periods of air. If this is not an alternative then you will have to seriously think about ditching the bladders and going to a hard tank with a built in sump and baffles. If you do that then you will have to have the returns to the sump to maintain fuel around the pickup when it starts sloshing to the front. A simple flapper valve baffle that traps fuel around the pickup will do the job. Like an oil pickup baffle. The only other alternative I see is to add pickups to the front of the tanks. Even then some of the pickups will be drawing air. Maybe some sort of toilet bowl action that would shut off the pickup line when the fuel is low forcing the fuel to be pulled from the other end of the tank???? Does "that" make any sense??

Bill

 

[Ian Anderson]

I agree with Bob - I use a Red Top Facit as my Low Pressure pump.

But then again I am running a Rover / Morgan lump that runs 250 - 260 hp and the ret top will cope

Depending on how thirsty your motor is a red top may mot be able to keep up with demand.

I know that from half tank level down I can cavitate the pump when slowing for roundabouts - my pick up is at the rear of the tanks and tanks have Explosafe in them (Wire wool stuff not foam). When the Facit sucks air you can hear it is it really hammers away!

Ian

 

[Chris Kouba]

I know that from half tank level down I can cavitate the pump when slowing for roundabouts - my pick up is at the rear of the tanks and tanks have Explosafe in them (Wire wool stuff not foam). When the Facit sucks air you can hear it is it really hammers away!

As long as it keeps on pumping without burning up, that's all I care about. It sounds like your tank situation is quite like mine.

Would this be the one:

https://www.pegasusautoracing.com/productdetails.asp?RecID=8462

I have a relatively mild mill compared to others on the forum, only ~350h/350tq at the flywheel. I usually only run one pump but if I seem to draw it down, I can flip both switches and feed the swirl pot from both sponsons at the same time.

CK

 

[Chris Kouba]

If you don't have access to the interior of the bladders then you will have to use a low pressure pump for carbs. to 1. get fuel to a sump or to a swirl pot, or 2. to survive the periods of air to the pump.... Does "that" make any sense??

Yep, and that's actually what my system already is. Two LP pumps (carb pressures), independently switched, which feed the swirl pot. The EFI pulls a loop from the swirl pot with a HP pump (~90psi if memory serves me) and returns to the pot. There is a single return line from the swirl pot which T's to feed both tanks (in theory, but usually just the left one due to the shorter length of return). I manage the tank levels via running each pump individually or concurrently. I thought I'd try this configuration as it saved me from having to figure out the Pollak valve thing.

I like the safety aspect of the bag tanks so I am disinclined to ditch them, I was hoping to find a pump which can deal with the circumstances and still provide the needed volume. Hopefully the red top will fit the bill as the type I have currently clearly does not.

Chris

 

[Ian Anderson]

As long as it keeps on pumping without burning up, that's all I care about. It sounds like your tank situation is quite like mine.

Would this be the one:

https://www.pegasusautoracing.com/productdetails.asp?RecID=8462

I have a relatively mild mill compared to others on the forum, only ~350h/350tq at the flywheel. I usually only run one pump but if I seem to draw it down, I can flip both switches and feed the swirl pot from both sponsons at the same time.

CK

Hi Chris

Yes that's the one

Ian

 

[Mike Pass]

Holley 150s will do the job. I would suggest overspecifying the pump capacity because if the pumps are only just up to the job when you get a bit of a blockage in the filters the engine could run lean. Having recently seen the melted pistons that result and the mess and the cost of rebuilding the engine make sure that you get the flow you need. The facet pumps weren't up to supplying a 347ci driven flat out.
Cheers
Mike

 

[DaveM]

Holley 150s will do the job. I would suggest overspecifying the pump capacity because if the pumps are only just up to the job when you get a bit of a blockage in the filters the engine could run lean. Having recently seen the melted pistons that result and the mess and the cost of rebuilding the engine make sure that you get the flow you need. The facet pumps weren't up to supplying a 347ci driven flat out.
Cheers
Mike

I would not recommend Holley fuel pumps period. I had 2 gerotor ones and 1 red pump fail on two different vehicles in the last 2 years. Holley used to make quality parts 25 years ago. Now it's Chinese junk.

 

[Chris Kouba]

In the end, I ordered up a pair of the 480532E Facet red tops from a marine supply shop at a decent savings compared to Pegasus:


Facet Cylindrical Solid State Electric Fuel Pump - 480532E - Discount Yacht Supplies, Vetus Nautical Accessories, Scandvik Parts, Garmin Marine Electronics

I did get one installed and it looks like it's working properly. The swirl tank fills and has flow returning to the sponson with the motor running. The pump was a little loud when first powered up, but the noise was thoroughly drown out once the motor fired up.

Next up is a little bit of a shakedown run, but still dealing with a few other sorting issues. I think I will be pretty happy with them if they continue to function.

Chris