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I just received my rebuilt fuel pump and it looks awesome. In talking to the rebuilder, he was telling me that I should use a electric pump and filter some where before the mechanical, I asked why the pump ????? He said it helps the fuel pump if the car has been sitting for awhile.......but wouldn't i run the risk of over pressirizing the needle seat running 2 pumps?????? And I'm not sure if you all run filters???? If so where??? I was thinking about putting a filter down where the rubber hose hooks to the pump and the supply line?????

Electric fuel pumps are used by many of us here to argument the mechanical ones on the engines. Electric pumps are good for priming the fuel system after the car has been unused for a period of time. These pumps are also helpful to avoid vapor locking. We don't use them full time but only for brief sessions to prime and overcome vapor lock. The pumps need to have a filter in-line mounted before the electric pumps to avoid contamination of the pumps. Some come as a kit including the pump and filter assembled.

Many of us run an electric fuel pump mounted near the tank that can be switched on and off as needed. When the car has sat for awhile, a few seconds running the electric does help in replacing fuel that has evaporated or percolated in getting thru the pump and into the carb without a lot of cranking time. A secondary benefit is turning it on during vapor lock situations will place the suction line under a small amount of pressure which can help that issue. Modern gas is quite volatile and it has been suggested that vapor lock actually occurs in the suction side of the pump where the reduced pressure will allow the volatile bubbles to more easily escape and form a large air lock which the mechanical pump finds difficult to pull thru.

There are two type pumps. For the most part rotary pumps are quiet but mechanical pumps sometimes find it difficult to pull fuel thru them. Usually a check valve and bypass plumbing around the rotary pump is needed so the stock pump can pull fuel. Carter makes a 6v unit that some have used. A solenoid type pump has valves similar to what is already in the mechanical pump and when that style is turned off the mechanical pumps can pull fuel thru with only a minimal amount more effort. As long as the electric pump has pressure output suitable for the situation there is not much danger in overpowering the carb float valve. If you are really concerned then a pressure regulator could be added but many of the inexpensive regulators do not really do much good at such low pressures.

Airtex makes a couple of solenoid style pumps suitable for our use. Both are 6v, can be wired for positive or negative ground and sized for 5/16 line. They do have a small filter attached and both will install with minimal effort. Because the small pump filter is attached many add a larger capacity filter which has a removable element that can be serviced in the line before the pump so it traps debris from the tank before the one that comes with the pump.

The E8011 has an output of 5-8 psi and when mounted near the tank the line length and fuel being pushed thru the mechanical pump and any optional filters is usually enough to lower the pressure at the carb to an amount almost equal to what the mechanical pump would normally output. The E8902 has a lower output at 2.5 - 4.5 psi and could also be used if you wanted one that more closely matches the mechanical pump. It would be the better choice if the the mechanical pump was removed or if the standard screen mesh in the pump is the only filter and there are no fine pore filters such as the ceramic option Packard offered. Amazon sells the Airtex brand as does many parts stores.

Hey Pat,
Not sure where you got your rebuilt from, but those fresh re-mans sure look nice, don't they?!? All your questions answered already, but one thing I have been wondering and thought I'd throw in here as an additional query - if the electric pump is back at the tank and it is engaged, can it put pressure on the diaphragm of the mechanical pump, possibly damaging it and allowing gas to be able to be pumped into the engine?? I have my electric pump mounted at the tank and have a toggle switch under the dash. I normally only use it in short bursts, as suggested to prime the carb when the car hasn't been started in a while, but I have had a 'senior moment' and forgot to turn it off. I wondered afterward if I could have hurt the mechanical pump?? I've even thought I should change the toggle to a 'spring-on-only' version so that can't happen. Am I worrying about nothing here?!?!? Chris.

Hey Chris, I had Arthur Gould rebuild the pump, it looks cherry and they said it passed the bench test just fine. That's a great question, and now I wonder if you/someone else has ever had any problems with the mechanical pump pulling through the electrical pump???

I only ever had an electric pump in one Packard and only because it came with it (a 1953 Clipper Deluxe) and it was easier to leave it in. Some pumps have adjustable pressure so shut off when not needed while others just keep pumping. Mine was the diaphragm type which will still pass fuel through from the mechanical pump even when shut off but other types need to run all the time or they'll block the flow.

Bottom line is I can see no reason to install an electric pump and they may just be patches to cover another problem that needs addressing first. If the mechanical pump is in good condition, its valves should minimize fuel running back to the tank when sitting for periods of time.

I would, however, use a filter at all times and prefer the factory type if for nothing other than appearance. The modern in-line filters look odd to me in an old car.

I have used electric pumps on our '37 Super-Eights for 30 years. Down here in the Houston area, when it is 95 degrees and I stop at a long light, I am guaranteed that when the light turns green and I accelerate....500 feet up the road, the engine will start faltering. Turn on the electric...and away I would go.
I use the spring loaded switches ever since I left a switch on and a week later I had a dead battery.
ALSO....I not only have a visible filter in front of the electric pump (why let junk mess up your pump?) and an inline cutoff switch to make it easier to change the filter.

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Hey Don thanks for the info, I am thinking I will give just the mechanical fuel pump a shot, crossing my fingers that the lobe on the cam is still good!!!!

But you mentioned that you would use the "factory type" i was under the impression that they didn't use one ??? ......do you have a picture of what one would look like???

The "factory type" was referring to the regular glass bowl filter that attaches to the inlet of the carburetor and the line from the pump connects to it. They were a common accessory that is still available but with a modern replaceable element rather than the washable ceramic element of the original. I have several new one at my Oregon shop if you can't find one more quickly.

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PackardDon wrote:
The "factory type" was referring to the regular glass bowl filter that attaches to the inlet of the carburetor and the line from the pump connects to it. They were a common accessory that is still available but with a modern replaceable element rather than the washable ceramic element of the original. I have several new one at my Oregon shop if you can't find one more quickly.[/quo

Not in a hurray at all, do you have a picture of one i may have one< sounds like one i had for my 56 Belair