Eating fuel pumps

Pontiac Pete · #1 (**permalink**) 07-29-2010, 09:01 PM

Can anyone tell me why I keep killing fuel pumps? Lost the pump that came with the kit on power tour, About 2400 miles on pump. The people at the comp cams tent were no help. John @ tech support got me a part # to order one from O'reilly. They crossed it to another # It made it 200 miles and died. Bought aeromotive #11106 and it made it 350 miles. Regulator is at 43psi, 5/16 return line is open and free flowing. Ez-EFI ran flawlessly on tour and runs flawlessly still just eats pumps. Any thoughts?

FAST Tech Maxwell · #2 (**permalink**) 07-30-2010, 02:10 PM

Well we can definitely say it is not a fuel pump problem!

I don't think your pressure side and return line are really the problem.

EFI pumps can be damaged by running them dry. I would look at inlet restrictions or possibly a hole or broken place in the pickup tube/line in the tank that's letting the pump suck air. Also, make sure the pickup is actually drawing from the bottom of the tank.

Heat can hurt the pumps, too. Make sure it is not close to an exhaust pipe or maybe even the rearend housing.

Pontiac Pete · #3 (**permalink**) 07-30-2010, 09:54 PM

Gonna drop the tank tomorrow. Inlet is solid piece of 3/8 tube welded in to tank. Most likely not the pickup. Never been run dry as it's a 13 gallon tank and at refueling stops on the tour I never put more than 7 gallons in. Pump is mounted to center of fuel tank in front of differential. At least 18" from exhaust. Will make sure pick up is on bottom. Thanks for the input Max as any help is good.

turbodon · #4 (**permalink**) 08-01-2010, 03:11 PM

Pontiac Pete

I am afraid that your problem is pump run dry. (Run dry = momentary loss of fuel to pickup)

We went trough 4 Aeromotive $400 dollar pumps on a road race car ( $400 x 4 0. We a have a dual fuel tank setup.

On a n EFI race car, you need to run a surge pot (surge tank, and other names).

1) You use a carb pump in free flow from the fuel tank pickup to fill the surge pot ).
2) You return from the very top of the surge pot back to the Fuel tank.
3) You pickup from the bottom of the surge tank for the EFI High pressure pump.
4) You return fuel rail back to surge pot (about 3/4 way up from bottom).

This keeps the fuel High pressure pump from running dry.

The Aeromotive pump uses stainless steel pucks between billet aluminum for the rotor of pump.

As you loose fuel to pump ( corner , breaking, accel ) and fuel back on pump, the pump cavitates briefly. This cavitation causes the stainless steel pucks to wobble. This wobble eats the aluminum and pumps dies. This only takes seconds.

Pull one of the pumps apart and look at the rotor assembly.

Pontiac Pete · #5 (**permalink**) 08-09-2010, 07:52 PM

Took the tank out, pickup on the bottom. Disassembled pump, aluminum wow wowed as told by Turbodon. Well thanks for the help as I am ordering a new tank with pump inside where it belongs! Happy motoring, Pontiac Pete

David_H · #6 (**permalink**) 08-22-2010, 09:35 PM

My pump just locked up today

if they don't work outside the tank maybe they should put that in the directions....Hope they warranty the pump....

TurboNova · #7 (**permalink**) 08-23-2010, 02:56 PM

You have to remember all pumps have a "pump head" value. This is the vertical lift the pump will be able to pull fuel out of the tank. So if you are trying to use a stock pickup in an old carb tank and mount the pump on the tank or level with the bottom you are asking the pump to pull fuel up then down to the pump and back up.

I have a 66 Nova wagon with the stock carb pickup in the tank, I use the same pump as the easy EFI, if I let the fuel level go below 1/4 tank the pump will suck air in corners. I don't let the tank get that low and have had the same pump for over a year in my daily driver.

Having the pickup in the bottom, baffels, a swirl pot are all good things to do and some even required but in the end where you mount the pump is also critical.

David_H · #8 (**permalink**) 08-23-2010, 08:30 PM

I agree Brian with what your saying but I'm well within the limits of what the MFG suggests to mount the pump... I'm not even going to play games with it I want this thing to be a car I can trust and drive thats why I put the FI on it in the first place. again I don't want problems this happened with just under half a tank of fuel I got in the car after it sat for a hour or two....
what do you think of this as a fix.... http://www.tanksinc.com/index.cfm/pa...prod/prd84.htm

Pontiac Pete · #9 (**permalink**) 08-23-2010, 10:15 PM

Hey David, Call Scott at Rock Valley 815-645-2271. He can hook you up with a pump in the tank or a pump to put in your tank. He's not cheap but neither was this EFI. You want what I want. A smooth running machine for road trips. So don't get depressed by Brian's genius rhetoric about fuel pumps! Were not all idiots, Mr. Turbo! My pump inlet was 1/2" below the bottom of the tank. ALL ELECTRIC PUMPS SHOULD BE GRAVITY FED, as they have very little "pump head value." Scott is working on a tank for me now. Will gladly keep you updated. Soon to be happy motoring again! Pontiac Pete

David_H · #10 (**permalink**) 08-24-2010, 12:07 AM

Originally Posted by Pontiac Pete

Hey David, Call Scott at Rock Valley 815-645-2271. He can hook you up with a pump in the tank or a pump to put in your tank. He's not cheap but neither was this EFI. You want what I want. A smooth running machine for road trips. So don't get depressed by Brian's genius rhetoric about fuel pumps! Were not all idiots, Mr. Turbo! My pump inlet was 1/2" below the bottom of the tank. ALL ELECTRIC PUMPS SHOULD BE GRAVITY FED, as they have very little "pump head value." Scott is working on a tank for me now. Will gladly keep you updated. Soon to be happy motoring again! Pontiac Pete

I talked to Rock valley this morning 3-4 weeks to make a tank.

I think I'm going to buy that insert I posted and a new stock tank to install it in....