put in an electric fuel pump?

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Vinnie

Project manager "Project AmsterFoose"
7173 Mustang Supporter Member
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Location
Amsterdam, The Netherlands
My Car
1973 Mustang Grande 351C 2V, built on the very last production day (July 6, 1973) for Grande's.
Hi folks,

For my 73 I'm thinking of putting in en electric fuel pump. This is because I don't drive it much and everytime I do I have to crank 4-5 times before I get fuel to the carb again. I think so because after 2-3 weeks my see-through fuel filter has hardly any fuel in it.

Also recently I had my Holley carb replaced with an Edelbrock. Last week I had to drive slow for a longer time and at some point it sounded like it was low on fuel briefly. I'm thinking maybe it's sucking in more fuel than the pump can deliver at low speeds?

I googled a bit and learned there are pumps that you put inside your tank and ones that are outside your tank. Does one have big advantages over the other?

I'm curious to hear your thoughts, opinions and recommendations!

Thanks,

Vincent.

 
Edelbrock (and Carter) carbs are notorious for going dry after a couple weeks (sometimes even just hours) of sitting. They also heat-soak a lot easier than a Holley and should have a 1/4" thick insulator gasket.

I would simply replace you current mechanical pump with a new one, or maybe the Carter M6882 musclecar pump, and see if it solves your fuel issues. I never recommend an electric pump for stock applications, too much that can go wrong. Mechanical pumps are dead simple and work.

 
Nah - go for an electric pump. I had originally gone with a Holley Black (rollervane) fuel pump, but it was loud as Hell. I recently swapped it out for a Holley Mighty Mite (gerotor-style) and it makes hardly any noise at all.

My car has sat since April or May, and when I hopped in last weekend, I turned the ignition switch to "On," waited for the fuel pump to prime, tapped the gas pedal once, turned the ignition switch to "Start" and the car fired right up.

http://www.summitracing.com/parts/hly-12-427

Here's the fuel pump installed on the rear frame rail inside of the driver side rear wheel well.

newfuelpump1.jpg

And here's a splash/rock shield I made for it (just in case). Someone had left a lower splash shield from a Volkswagen Jetta or something at the Auto Hobby Shop, so I repurposed some of it for this project.

newfuelpump2.jpg

 
Both Hemikiller and Mister 4x4 have valid points. You'll need to weigh the pluses and minuses to decide which way to go. I've run electric pumps with few problems, just make sure you match the pump to the engine and load.

To answer your other question about in-tank pumps. They are high-pressure pumps for fuel injection systems.

 
Thanks for the advice folks! I'm going to look for a mechanical pump and hope that it will pump better than the current pump (which I think might be broken). Also I'm not looking forward to the extra wiring and fuel lines that are required for an electrical pump. It's not expensive so if it doesn't work I can always go electrical after all :)

 
Or you could run both. It's not hard to set up a priming pump that you turn on for a few seconds to fill the carb, then shut it off and run on your mechanical. I agree with the gerotor type and it is a pusher, not a puller, so it needs to be down low and protected.

Mechanical pumps are relatively cheap and easy to replace, when in doubt, replace it. Better now than on the road...because it will be dark and rainy. Electrics are easier to swap in an emergency and I prefer to have a known good spare.

Almost forgot, if you run an electric it is extremely wise to install an oil pressure shutoff switch and an inertia switch. They will shutoff fuel flow in the event of an accident.

 
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Problem with trying to run both would be the mechanical pump would have a hard time pushing fuel through the electrical pump if its mounted after the mechanical. or if its mounted before the mechanical it would have a hard time pulling fuel through it.

When I swapped a 302 into my 1989 Bronco II I tried to leave the in tank pump in place and pull fuel through it and it would not work.

 
I'll say it again, "My car has sat since April or May, and when I hopped in last weekend, I turned the ignition switch to "On," waited for the fuel pump to prime, tapped the gas pedal once, turned the ignition switch to "Start" and the car fired right up."

The "wait" [for the fuel pump to prime] period was about 2 seconds.

Just sayin'.

I don't buy into the whole "the electric fuel pump need to be lower than the tank" thinking, because my electric pump is pretty much even with the tank, having the standard pick-up/sending unit as the mechanical pump. The mechanical pump is higher than the tank and a helluva lot further away, but it still somehow works. "Pumping fuel" is "pumping fuel," regardless of whether you use an electric or mechanical pump to do so.

Maybe I'm wrong, but I don't think so, because it's just as I said above: the car fired right up after having sat for months.

I will be replacing the mechanical pump on my 1980 Jeep CJ-7 with the same exact set-up, because it sits for months on-end as well... and I also have to crank... and crank... and crank before it'll start.

One (1) fused wire from an Ignition On source, about 8" of fuel line, some clamps, and a $45 Holley Mighty Mite fuel pump (or even the $38 Mr. Gasket version of the same pump), a Mr. Gasket Block-Off Plate (for the mechanical pump) and you're done. You may have to split a hard fuel line and use a flare tool for make "bubble flares," or just find a place in a location with a soft hose fuel line to work the pump into the line. $70 is a feasible cost for this.

 
I think the difference is that the mechanical uses a diaphragm which creates vacuum. Virtually none of the electrics (that I know of) create much vacuum and don't really pull fuel very well. They seem to work much better with the fuel already inside the pump and just move the liquid. I've used electric pumps on my Opel for over 10 years and noticed a significant difference when I switched from an engine bay mounted electric (the square block type) to a gerotor type mounted low and ahead of the gas tank. Although, I must say, the square block type didn't work well in the back either.

As for running two pumps, they would have to be parallel, not in line with each other, or two separate fuel lines entirely. Depends on how important this is. I think in this instance, the issue is the carb going dry, so an engine bay mounted electric with 'y's before and after the mech pump may suffice to prime the carb but not actually run the car.

 
I have an in-line pump mounted on a front frame rail on my other Mustang for 6 years that I can speak for, without any issues.

I had to install a fuel regulator to bring the pressure down to about 7psi from 13.

Sent from my SPH-L900 using Tapatalk

 
Well, I'm gonna get me a Carter mechanical pump and see if that solves anything. It's cheap and fun and not too hard to do myself I reckon. I also do not look forward to running extra cables etc for an electrical pump close to the tank.

I'm wondering about one thing though, maybe you guys know the answer... The new Carter pump will give 5.5-6.5 psi at the carb. Howmuch pressure does the original pump from Ford (the 42 year old one I mean) deliver?

Cheers!

 
When I had the 351C in it had an Edelbrock hi-perf mechanical pump. Even with an insulated spacer under the Holley, after leaving it for a week or two I would have to crank it for ages. If I left it for months due to working on the car, I often had to charge the battery to have a chance of starting before it went flat.

When I put the 429 in I installed a new high flow Carter electric pump I'd had in stock since 1990. It's a bit noisy but I stuffed the rear fender dropoff where it's fitted and the pillar above with sound deadening & it's not audible when the motor is running.

I absolutely love the way that even after a few weeks I can turn the key to run, count to ten, turn to start, blip the throttle & she roars into life like an injected motor. Safety switch to be installed soon! Must save a lot of wear on the starter too.

 
One other bit, if you do not have a brand new tank you know to be clean...actually, it doesn't matter what condition the tank is in if you don't drive it enough, gas breaks down into crud...install a good quality fuel filter between the tank and pump. Mech pumps are a bit more forgiving, but electrics will get chewed up by crud from the tank.

 
Both the Holley and Mr. Gasket pumps I mentioned, each come with inlet filters. :cool:

 
My car will sit for a month or so. I had the same problem as you. I solved it with a bottle of starting fluid. I spray some into the air cleaner and it fires right up. The higher RPMs gets the mechanical pumping enough to get the fuel flowing again.

 
My car will sit for a month or so. I had the same problem as you. I solved it with a bottle of starting fluid. I spray some into the air cleaner and it fires right up. The higher RPMs gets the mechanical pumping enough to get the fuel flowing again.
If you are going through the trouble of opening the hood, just fill the primary float bowl with gas via the vent.

It will idle for a while like that....plenty enough time to prime the pump and have it take over.

 
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