To All,

I have seen some posts here on running electrical fuel pumps as a "booster" for your mechanical pump, so I thought I might add my little recent experience...

The car is my 1971 Charger R/T 440 Magnum. I was having a little fuel delivery problem (when cold or high RPM WOT), and had an idea.

Basically, I mounted a small Carter cylindrical electric fuel pump (P74029)where the steel line from the tank ends in the right front fenderwell area.

Being a "Wiley E. Coyote" type , a mounted an inline fuel filter right before the pump, and wired the power feed off the ignition wire. The wire went through a JEG's low oil pressure (5PSI) switch, and a Snow Performance vacuum switch which energizes at 5 inches or less of vacuum. This means the engine has to be running and near WOT for the pump to come on.

Finally, I ran a green LED light to the instrument panel, along with a toggle switch. The light comes on when the pump comes on, and you can use the toggle to fill the carb bowl on cold starts, or when the car hasn't been driven much.

Immensely proud of myself , and enjoying plenty of gas at WOT, I decided to take the Charger on a 200 mile trip yesterday. When the wife and I arrived at our destination, I noted that the mechanical fuel pump was leaking quite a bit. The pump is ten years old, so those things happen. I simply bypassed the mechanical pump, and kept the electrical pump on full time.

The thing did not last the day, and gave out on us during the trip home. Due to the risk of fire from the leaky mechanical , I had one brought out from my stash at home and replaced it road side. Made for a long night; luckily my wife is a real hand and was very helpful during the ordeal. Guess that is why we are celebrating our 25th next March.

Now, has anyone heard of electrical pumps going out so fast? I know I had it mounted in a less than perfect position, but I know of guys who have run pumps in this manner for years day in and day out. The pump was mounted at least six inches from the headers, so I don't think excessive heat is the case.

Are Carters of this type having issues, or did I just get a bad one? Also, does anyone have other recommendations?

May God bless America,

Paladin

electric pumps are designed top pump fuel, not suck it, and they should be close to the tank....but I think you just got a bum pump.

Next time mount the electric pump as close to the fuel tank as possible. Like said, electric pumps are designed to push fuel not pull it. My engine builders Road Runner has the same fuel system set up as you (his electric pump runs constantly, though) but mounted the electric pump near the fuel tank and has had no issues.

Oh darn, JohnRR treed me.

check the oil for gas,if the mech pump was leaking it could have dumped fuel into the oil pan

saw a couple BB bite the dust over a bad fuel pump



no elect pumps under the hood,allways at the tank

you do have a good idea on the power,vac switch,led light,toggle switch

some might say its over kill,but sounds like a good way to run one,just need the pump at the tank,IMHO

nice pic of the cars too

Are you sure you were getting a full 12v feed to the pump?

ez-er to suck a short distance and pump it long distance than the other way round

depending on the pump IMO

i used a MALLORY vane pump for yrs and had it many different places and it still worked fine..i suspect yours was just cheap junk...also change your oil in case.. dan

You young whippersnappers obviously never siphoned gas out of a car. You use the shortest hose possible, imagine trying to suck gas through a 6 foot hose. Same principle applies here. Get the pump as close to the tank and as low as you can. It keeps the pump cooler cause it don"t have to work as hard. That being said on a stock Mopar theres no place to mount one low, mine is on the frame rail.

There is also a good possibility that the electrical pump caused the mechanical pump to fail ( leak ). They are not ment to be run with pressure on the suction side, especially if it is a stock style mechanical pump. My suggestion; dump both pumps ( that carter you bought is a real woosy of a pump ) and buy a real electrical pump ( gear rotor ) and mount it by the tank. What you did was to cover up an impending problem. While you are installing a decent electrical pump, up grade your fuel lines from 5/16" to 3/8".

...If it's an original 440 R/T would it not already have a 3/8" line and a 1/4" vapor return line, or did Chrysler change that after 70.

Yeah it's my understanding a mechanical pump is not designed to be pressure fed. I wonder if that electric pump popped the diaphram? I'm putting one of the new holley pumps on my GTX. (Billet roller cam so I can't run a mechanical.) The holley is big and heavy and there's just no good way or place to mount it in the back. I mocked up a bracket in cardboard yesterday to mount it to the floor just ahead and to the right of the diff.

I didn't read the whole thread, but filters go after the pump, not in front. Doesn't surprise me the pumps quit working, the whole thing sounds like a bad idea to me.

...Fwiw, ...there are bronze tipped fuel pump push rods for Chrysler's. Haven't used one yet but headed that way.