Mechanical vs Electric Pump

[Jaybot]

Had an electric pump previously on my 63 R1 Avanti, but when I changed over to electronic ignition my mechanic said I would be better off to use the Studebaker mechanical pump instead of electric. Good news is that it always starts but does not start as easily as it did when I had my electric pump. I really expected a lot better results especially since I changed over to the electronic ignition as well. Should I go back to the electric pump?

[Gunslinger]

The problem isn't the pumps but the gasoline that's available today. Today's gasoline is blended for fuel injection (as well as low emissions), and evaporates much quicker than older blends did. Whats happening is the gasoline in the fuel bowl is evaporating and it takes time for the mechanical pump to to get enough volume into the carburetor and have it atomize before it gets into the combustion chambers. The whole process is faster with an electric fuel pump.

An electric pump is more efficient at pushing a liquid than a mechanical pump is at pulling the same liquid. It will also eliminate vapor lock where a mechanical pump won't.

Whether you keep or change the mechanical pump to the electric is your call. Whether the ignition is breaker-type or electrical is really immaterial to the type of fuel delivery.

[PackardV8]

when I changed over to electronic ignition my mechanic said I would be better off to use the Studebaker mechanical pump instead of electric.

Things than make you go "Hmmmmm? That's the strangest recommendation I've heard lately. Use the electric - hope you've still got it.

jack vines

[Jaybot]

Thanks for the input. I'll go back to the electric. This particular mechanic specializes in old cars and did some decent work in other areas so I figured he knew what he was talking about. But fact is it definitely performed better before the change. Hope he wasn't just trying to pump some money out of me? I found a new guy to work with since then anyway.

[bams50]

Some use both- mechanical with electric as a backup. To the knowledgeable, is this the best way to go?

I am always a bit underconfident in aftermarket electric pumps... I like the concept of stock, with the electric for priming and vapor lock, and the added benefit of backup. I know modern cars use electric pumps that go hundreds of thousands of miles trouble-free, but they're in-tank and engineered specifically for the application. Listening to an aftermarket pump rattle is hardly confidence-inspiring.....

[Chucks Stude]

The concept of an electric pump is especially intriguing considering the fuel that we have today. My concern is what happens in a roll over, or accident? The pump keeps running. There is some talk about tying the pump to oil pressure, but how do you get the system to work on startup with no oil pressure?

[53k]

The concept of an electric pump is especially intriguing considering the fuel that we have today. My concern is what happens in a roll over, or accident? The pump keeps running. There is some talk about tying the pump to oil pressure, but how do you get the system to work on startup with no oil pressure?

Use an over-ride push button switch you can hold until oil pressure builds enough to switch on the pump.

[PackardV8]

The concept of an electric pump is especially intriguing considering the fuel that we have today. My concern is what happens in a roll over, or accident? The pump keeps running. There is some talk about tying the pump to oil pressure, but how do you get the system to work on startup with no oil pressure?

Fords with EFI used an impact/rollover switch which was located in the trunk. I've installed them where there was concern about the safety aspects of electric pumps.

jack vines

[Johnnywiffer]

When I bought the car, it had a Walbro electric pump mounted in the hump in front of the gas tank in my 12v '54 LC. I used it only for starting because the car sometimes sat for many moons between starts. I have a little toggle switch mounted under the dash by the emergency brake. I'd flick it on until the bumping sound stopped, start the car, then turn it off.

This wonderful pump gave out after probably 10 years of service. I priced pumps of that type for replacement and found them in the $100 range. However, in the Corvair section of Ebay, there was a pump for around $50. (They are now around $60.) Different kind of pump but was highly recommended by guys on the Corvair Forum. Ordered one and put it on. Not only is it quieter than previously, it seems to fill the carb much more quickly. I still turn it off after priming the carb.

Is it as good and will it last as long as the previous one? Ask me in 10 years.

John

[PlainBrownR2]

mmm, Walbro, that name is a staple for the DIY fuel injection guys as well. LOL, they are even sold from the same DIYAutotune.com site that I picked up my Megasquirt box from so you know it has to be good! I have a variation of the Walbro on the '55, mainly because the pressure requirements are not available with the Holley pumps that are usually used with the carbed cars.

Yeah, our 95 Crown Vic has that inertia switch. In the event of a rollover or being bumped violently from the rear, the switch turns the pump off. It's mounted to the side of the trunk with a reset switch on top, so if it switches off you can pop the trunk and turn it back on. We only had one pretty rare and unlikely instance where it did that though, and that was due to an unusual circumstance where the grooves that were cut into a shoulder on a freeway onramp set off a rythymic vibration that triggered the switch to shut off.

[1954khardtop]

The inertia switch and oil pressure switch are both great ideas. Also the momentary switch you hold 'til the pressure builds. Years ago I filled the crankcase of my Stude with gas. I had an electric pump with toggle switch hooked to the bat. post of ing. switch, and forgot to shut it off. After that I wired it to the ign. post thinking that would be safe. I never considered what could happen if the engine stalled and I was unable to shut off the switch. Gotta go out to the garage, got some wiring to do!

[Clem64]

I have a NAPA oil pressure switch on Clem's electric pump setup. Priming is not needed on startup as the switch pressurizes almost instantly. I plan to add the Ford impact switch also. The pump is a Facet 4psi. and it is very quiet to me. I completely removed the mechanical pump and used a Chevy blockoff plate to cover. I will convert the Hawk next as it will presently only run with the expensive non-alcohol premium.

[curt]

The local 'junk dealer' charged me ten bucks for a used impact switch, off a Ford Tarus,

[Relark]

About a month ago, I installed a Holley "Red" pump as the stock mech pump would not keep up under accelleration. After about 10 minutes of driving, the engine died, checked fuel pressure, zero, coasted to the middle lane on a very busy 5 lane 45mph city street. Checked the pump, it was very hot. The local sheriff pulled up behind with his overheads on. Stayed with me 'til the tow truck came. Called Jegs tech line, talked with the rep, and he agreed there was nothing wrong with the install, wiring, relay, grounds, etc.. He told me the return rate on the Holleys are 15%! They say "Made in USA" on the bracket, but he told me the pump is made in China. Bought an Edelbrock made by Essex Industries, suppliers of pumps for F16 fighters, etc.. Actually made in USA.
This has been my experience with part failures, China made Proform dist. , Jegs knock-off Fram type fuel filter, now Holley. Ordered MSD dist., told it was made in USA, big letters on the box "China". Sent it back for full refund. Talked to Mallory, got in a Uni-lite, 100% made in USA.
My money doesn't come easy, try to always buy a name brand. I guess you can't assume anything.

Art Rigsby

[N8N]

The concept of an electric pump is especially intriguing considering the fuel that we have today. My concern is what happens in a roll over, or accident? The pump keeps running. There is some talk about tying the pump to oil pressure, but how do you get the system to work on startup with no oil pressure?

The neatest solution to me is to use a Volkswagen fuel pump relay, which relies on sensing ignition pulses. When the pulses stop, the pump stops. It does have a several second "prime" function that lets the pump run when you first turn the key on; if it doesn't detect ignition pulses after several seconds, it shuts the pump off. A nice "transparent" solution to an electric fuel pump. I've posted about this here before...

http://forum.studebakerdriversclub.com/showthread.php?19060

Unfortunately, the job of getting the FP actually installed and wired up keeps getting bumped due to other things happening, so I can't give the concept a complete thumbs up yet.

The one downside to this otherwise elegant solution is that the VW relays are known to fail somewhat more often than one would desire - so having a spare in the glovebox (or at least some scraps of wire) would not be a bad idea.

nate