Airtex fuel pumps
 

Went to buy an Airtex 6 volt low pressure (2.5 to 4psi) fuel pump, model E8902 based on a lot of positive comments I've read on this forum. As part of the online (Ebay site) information on the pump I came across these statements in red "This pump can be used for either positive or negative ground. FOR POSITIVE GROUND The pump itself must first be wrapped and electrically isolated from the mounting bracket you may or may not have to reverse the wires." What gives? Has anyone done this or had to do this on their installation?

Re: Airtex fuel pumps
 

Yes I have done this. When I first installed my E8902 I tested it and found that even though it was running no fuel was coming out at the fuel line into the engine. I knew for sure that the lines were good as everything was new. I pondered for awhile until i realizes the Ford was positive ground. I had wired it + and - per the connections on the pump. I reversed them and the pump runs fine. I don't recall my instructions mentioning wrapping the bracket. I didn't by the way.

Re: Airtex fuel pumps
 

The manufacturer must recognize some possibility of the negative windings contacting the case of the pump. For the sake of safety and the possibility of a failure at some future point, I would isolate the pump from whatever it is mounted to. This would also require rubber hose connections instead of steel tubing connections.

Re: Airtex fuel pumps
 

I didn't wrap mine and works fine with pos. ground.

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Re: Airtex fuel pumps
 

I bought one a couple years ago that would not work,the E8902. I called the seller and he got me hooked up with an Airtex tech. The tech insisted that the pump would work on either positive ground or negative ground but added just make sure the black wire is connected to your your ground,---what??? I sent it back but after I keep seeing others have used these successfully I have purchased another one to try again.Would really like for this to work as a backup, couple years ago I had a mechanical pump fail on a very busy two lane within a mile from home. I still believe this low pressure pump is actually a 12 volt pump that will or supposedly work on 6 volts at half the 12 volt pressure hence the 2-4. Airtex acts like they were made "specifically for your antique,what was it"?

Re: Airtex fuel pumps
 

Like Vic indicated...just reverse the wires on the pump. Should work fine. I have installed 3 or 4 of them with no issues. Good luck. Pat

Re: Airtex fuel pumps
 

I mounted mine using a hole that was already in the frame to bolt the bracket to, hard plumbed to the metal tubing rather than using the short rubber hoses and spring clamps that come with the pump, no insulation of the pump body from the bracket or frame. Just reverse the wire to ground the positive and run the negative through the dashboard switch. (Have an inertia kill switch to shut down in a collision.)

http://i1059.photobucket.com/albums/...mpelectric.jpg

P.S. Unless you are just going to turn the pump on momentarily to prime the mechanical pump when vapor locked you'll need a pressure regulator as the pump will put out the maximum 4 psi which is too much for the carb float valve. I put the Holley pressure regulator between the electric and the mechanical pump. Even so, I had to adjust the regulator clear out to get the pressure low enough to not overwhelm my carb float valve.

http://i1059.photobucket.com/albums/...ps64f449f8.jpg

Re: Airtex fuel pumps
 

I have one installed on my 41. Bought it at Advanced Auto. Are they really any cheaper on e-bay? Cannot remember for sure but about $45?

Re: Airtex fuel pumps
 

When I bought mine (12v version) in '05, they were $25 at AutoZone. Now you're lucky to find one for $45, eBay or Summit. Same with the Holley regulator, it was $15, now it's $30. They must think us old birds are made of money...

Re: Airtex fuel pumps
 

hey, Ross....you forgot to turn off your blinker....could run down your battery....:D....Mike

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Re: Airtex fuel pumps
 

Sad to admit but that left blinker is NOT only a Utah trait. It is alive and well in Georgia.

Re: Airtex fuel pumps
 

Got my airtex pumps from Amazon

Re: Airtex fuel pumps
 

Re: Airtex fuel pumps
 

Cheapest price I found is at Amazon.com ($39.30) + free shipping. Airtex E8902 More and more I check prices on Amazon.com and find them cheapest.

I also installed an inertia switch as Old Henry suggested.

Re: Airtex fuel pumps
 

Holley sells an oil pressure switch that you can run power thru, the idea being that if there's a leak in the line out of the pump, the engine will die and it will shut off the pump to prevent a fire. On modern cars they use the computer to detect whether ignition pulses are present or not, and EFI engines will stop almost immediately on loss of fuel pressure. On our cars, the oil pressure switch is for some kind of crash where the line gets ruptured and the driver is unable to shut off the ignition. In normal operation, by the time the carb has run out of fuel, and the engine stopped, you've pumped a lot of gas all over the place, can smell it, or see the flames.

Obviously if you use the switch, you've got to provide power to the pump until you've got oil pressure (probably before cranking to fill the carb). Older Chrysler products had a timing relay that energized the pump for 5 seconds after the ignition was energized, or when the starter was activated. That would be perfect but I can't find one.

http://www.holley.com/12-810.asp

Re: Airtex fuel pumps
 

I used Airtex pumps for several years but the two most recent ones I had both failed in a short time. A friend suggested the Carter 4070 pump and they both have held up very well. The Airtex's seemed to vapor lock, I was told due to ethanhol but have no proof of that.

Re: Airtex fuel pumps
 

I've been skeptical of claims of damage by gasohol, but I've passed thru Tulsa and other towns in OK a total of 4 times in the last year. I keep real close track of gas mileage, and it always drops significantly (20% or more) on tankfuls purchased in OK. I suspect they are adding more than 10% ethanol around there. That will indeed start to damage lots of components.

Still, I drove thru there 2x in my truck, which has an Airtex pump, no problems.

Re: Airtex fuel pumps
 

I dont know about more than 10% ethanol in Oklahoma gas but 100% gasoline is readily available statewide. About 4 to 6 years ago it was all 10% etoh but slowly they started to offer 100% gas, now you can get it at most all stations. you have to pay a little more for it though.

Re: Airtex fuel pumps
 

Obviously if you use the switch, you've got to provide power to the pump until you've got oil pressure (probably before cranking to fill the carb). Older Chrysler products had a timing relay that energized the pump for 5 seconds after the ignition was energized, or when the starter was activated. That would be perfect but I can't find one.

http://www.holley.com/12-810.asp[/QUOTE]

Thanks Ross....but I've got a '40 Coupe and was just wondering where people prefer to pull the power for the switch, or pump? From the coil side of the ignition switch? Should a relay be used if not using the Holley switch?
Joe

Re: Airtex fuel pumps
 

The pump does not pull enough current to need a relay for that reason. If you're not going to use an inertia kill switch you can pull the power from the coil or accessories terminal of the ignition switch.

Re: Airtex fuel pumps
 

I installed a NZ made one and it is the best thing I ever did. Only use it for priming and is activated by a spring loaded momentary switch so it cant be left on in error.

GB

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I'm on my 3rd Airtex pump in 3 years. They seem to fail right after the warrantee is up.

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The Airtex pumps are not any better for late model cars with pumps in tank.

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I agree with Prof. Taking the power from the coil side of the switch means the pump switch can't be operated with out the ignition lever flicked up into the on position.

GB

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Thank you for the information. I was working yesterday on the fuel system of my '46 Ford, and just removed a Walbro PEG electric fuel pump dated "1-67", so I will be buying an Airtex unit and a regulator.

Re: Airtex fuel pumps
 

Got mine from Amazon too, great price, per Planojc's post. I had a Carter that I rigged for bypass with a one way valve previously. Why I didn't go with the Airtex before I will never know, With the Carter you had to have it on all the time even with the bypass. Since I have installed the Airtex, it runs on the mechanical pump all the time and the Airtex serves to prime when I let it set for a couple of days or more. This is the first time in 4 years it has run on the mechanical pump by its self and it was great.

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Roger:

My mechanical pump did the same thing. It will be interesting to see if it still keeps doing it now that I will be useing just the mechanical pump 99% of the time. Possible the electric pump was a but strong for the mechanical pump seals.

Re: Airtex fuel pumps
 

Hey guys, cant remember the exact cost but I do know it was much cheaper at www.rockauto.com I bought mine a few years back and no regrets to date. BTW I wired a switch off ignition acc on my 40.

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When you install an electric pump why do you leave the manual pump, is it just for look"s ?. Can you use the carter brand 2-4 psi sold by mac"s like the airtex ? Will it pump thru the manual pump if it stops ?. An if the electric pump stops well the manual pull thru the electric ?. Lot of questions i know but i am new to the v/8 flat head.

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No gas should leak around fuel pump diaphragm if all is well with the pump. If fuel is leaking with electric pump running then it will be sucking air when the mechanical is in use.

Re: Airtex fuel pumps
 

The carter pump will not let the mechanical pump pull through it when the electric pump is off.

Two pumps is the principle of redundancy. The mechanical pump is used until vapor lock or fails when the electric pump is ready for back up. If only the electric pump and it fails you're dead in the water.

Re: Airtex fuel pumps
 

There is no electric pump that will self limit to the 3.5 psi limit of the carb floats. So, any electric pump used more than just momentarily/intermittently requires a pressure regulator.

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Another question. A lot of people go to 12 volt. My car is still 6-v is the airtex e8902 for 6-v. I won"t to order one an won"t to be sure.

Re: Airtex fuel pumps
 

Yes. The Airtex E8902 is 6 volt. You can get it at AutoZone: http://www.autozone.com/autozone/acc...ntifier=963381

Or Amazon (That's where I got mine): http://www.amazon.com/Airtex-E8902-E...productDetails

Re: Airtex fuel pumps
 

[QUOTE=Old Henry;855648]The carter pump will not let the mechanical pump pull through it when the electric pump is off.

On my 8BA F1 the mechanical pump did pull fuel through the Carter pump (turned off), but only up to a speed of about 35 mph. After that the restriction inherent in the the Carter pump would not allow enough fuel to be supplied. This is why I had to install a bi-pass valve. I only use the electric pump to prime the carburettor - required if my pickup has not run for more than 3 days.