FYI-Fuel pump-6v electric

[Lou Earle]

Car quest has 6v fuel pumps - my store got them overnight from warehouse about60 bucks- the ebay ones are about the same when u factor in shipping- actually I get a discount 15 percent so a littl echeaper

the # is E 8011

Lou

[Reg Evans]

Will I create any problems by installing an elec. pump between the mechanical one and the tank and just switching it on to fill the carb for starting and then switching it off once the engine starts?

[Lou Earle]

I have installed them both ways before and after- makes no difference I think along the frame between tank and other fuel pump is perhaps the best but i have 3 that are installed on fender wells after fuel pump and they do great for pumping up also

[Ed Griffin]

I've never really had to mess with an electric fuel pump in the past and know little about the output psi if there is such a thing etc. On my truck the mechanical pump has been blocked with a plate and a electric fuel pump has been added some time back.

When I get the truck up to around 60 mph it begins to buck or surge. It will also do this if I am going up a long grade and have to really giver her gas, same as the other only not as badly because I let off some and it stops.

I've been curious if this could be because the fuel pump is not pushing enough fuel through when needed or a couple of other things that I have not checked out yet. Do you need a certain pump that push's the fuel at a certain psi or flow amount or do they all basically do the same thing at the same rate? Thanks, Ed

[Lou Earle]

all 6 v pumps I have found have a 5 to 8 # flow. Some 12 v have a 4 to 6 or 7# or psi flow. either is ok All my 5 to8 6 v work very

well.

I would check ignition first- be sure the points have the strong spring steel or a re enforcement spring- many leave this off and it can cause flutter at high=er rpm.

Lou

[Ed Griffin]

Thanks Lou! Even though I would possibly go that route with my 6 volt Dodge my problem lies with the 12 volt 283 in my 50 chev truck. It has a 57 283 with electronic ignition. What psi would you recommend for the small block? I need to go over the elec. ign. as well anyhow but not knowing the age of the fuel pump on it now or the psi so far I'd like to be prepared with the type needed if I do replace it. Thanks again, Ed

all 6 v pumps I have found have a 5 to 8 # flow. Some 12 v have a 4 to 6 or 7# or psi flow. either is ok All my 5 to8 6 v work very

well.

I would check ignition first- be sure the points have the strong spring steel or a re enforcement spring- many leave this off and it can cause flutter at high=er rpm.

Lou

[Plymouthy Adams]

On checking the pumps that Lou has...the pump has a output check valve in the outlet end to prevent backflow....you can actually siphon this valve open with a mechanical pump and fuel DOES flow through the electric pump...having one of these inline to fill the reservoir for quick start and switching it off is a working situation.

[Don Coatney]

all 6 v pumps I have found have a 5 to 8 # flow. Some 12 v have a 4 to 6 or 7# or psi flow. either is ok All my 5 to8 6 v work very

well.

I would check ignition first- be sure the points have the strong spring steel or a re enforcement spring- many leave this off and it can cause flutter at high=er rpm.

Lou

Lou;

What does an electric fuel pump have to do with ignition points? I do not think the two are connected

[Lou Earle]

Don

u r right not connected- but I had the same symptoms in my 46 and thought it was fuel and it turned out to be the omission of that second steel spring on the movable point- as soon as I put new points in the flutter/skip at high rpm went away.

Also A friend told me to use 4 to7 pound fuel pump on a 350 Chevy engine- he said more could overcome the small Chevy float resistance and overfill and overflow carburetor- he works with them every day I do not

Lou

[grey beard]

Everything you'alluns have said on this thread is fine by me. Having said this, please know that fuel pumps are traditionally tested for not one but two issues - pressure and volume.

Pressure, of course, can be tested with any gauge that reads in psi. Testing for volume is really difficult - with a warm and operational engine, disconnect your gas supply line at the carburetor and connect a rubber hose to it so it won't leak on your hot manifold, an stick th end into an empty can. Now start the engine on the fuel remaining in the carb float bowl, and let it idle for about thirty seconds. You should see a mimimum of one pint of fuel in the can in a thirty second idle run.

If you don't, check out your fuel lines, pick-up inside the tank, filters, etc., anything that can restrict flow. When you are driving on a hard pull under WOT - wide open throttle conditions - the engine will need almost this much fuel every thirty seconds - hard to imagine, but true. And the noise you didn't hear was four dollars a gallon leaving your wallet . . . . . .

[Normspeed]

I have a 6v under the frame rail near the back. On mine the one-way valve is at the inlet end. Same function. A mechanical pump can pull gas through the electric unit like it was a piece of fuel line. It closes to keep fuel from backflowing to the tank with the motor off.

My mechanical pump is just there for looks mostly, the cam arm is removed and there is a thin plate with gaskets between pump and block.

I like the electrics for a number of reasons including they can be used as an anti theft device if you are tricky about how they get power. Thieves just hate it when they steal your car and it quits in traffic within a block or so.

Lou, I notice the same number on mine, it came from autozone, for around $50.

[Lou Earle]

yep that is the same set up I have on the 47 4 door green I also have a working-I think- mechanical. I really know it works I do not run electric all the time.

Lou

[Normspeed]

One thing to watch if running the electric all the time is, if you have a very old mechanical pump still in the line, and the rubber diaphragm starts leaking, an electric pump can put lots of gas in your crankcase in a short time. One reason I just blocked off my mechanical where it bolts up.

[bob_amos]

I've got the exact same unit in my 53. As I recall it pumps at 7PSI. Sure makes starting after a long time sitting easy. Also, the added pressure to the line will help prevent vapor lock as it will increase the boiling point of the fuel. Mine comes on with the key and is on whenever the car is running. I just prefer that I don't have to mess around with any switches when I start the car and drive it. (Actually, call it too lazy to be bothered with a switch). I've thought of Norm's thing about the diaphram ruptuting and might just work something out on one of my old units where I can leave the pump in place and bypass the innards. I'll need to seal up the pump after removing the rubber diaphram but that should be real easy. A metal sealed disk in place of the diaphram and shaft will do nicely. Not sure if I will bother though. But I do like the unit and have installed it on a few customers cars too. Great little pump for the price.

[oldmopar]

I do not use a electric pump on my cars but do use a electric pump and a gas can to move around project cars.

When I purchased the pump there was something in the instructions about having a safety shut off with the pumps. Just curious if it is necessary and if anyone uses a shutoff.

Ed

[bob_amos]

Never heard of that on a vehicle mounted pump. But then my safety shut off is the Ign. key.

[claybill]

there are 2 kinds of electric fuel pumps....diaphragm type..and the electronic type..

please understand that most or all of the previous threads ARE REFERRING TO THE ELECTRONIC type, not the bellows or diaphragm type..

i have gone thru 2 bellows types, and towing costs, resulting from diaphragm failure......be careful.

comments?

claybill

[Normspeed]

The safety shutoffs I've seen involve routing the power lead through a switch activated by oil pressure. There was a writeup in auto restorer about that. I don't have a safety shutoff on mine.

[Don Coatney]

The safety shutoffs I've seen involve routing the power lead through a switch activated by oil pressure. There was a writeup in auto restorer about that. I don't have a safety shutoff on mine.

Norm;

If the switch is activated by oil pressure how does the engine get fuel at start up time? I was led to believe one benefit of an electric fuel pump is instant priming of the carburetor after the engine has been sitting for a period of time. And the engine has no oil pressure if it is not running.

[oldmopar]

I do not have the original instructions that came with the pump but as i recall it said something about routing through the oil pressure switch that normspeed described. I did not pay a lot of attention because as I said I do not use one but the information gave the impression that in a accident the pump would just keep pumping and cause a possible fire hazard.

It did seem strange as all new cars have a electric fuel pump maybe it was put there by lawyers to protect the company.

Ed

[Don Coatney]

I do not have the original instructions that came with the pump but as i recall it said something about routing through the oil pressure switch that normspeed described. I did not pay a lot of attention because as I said I do not use one but the information gave the impression that in a accident the pump would just keep pumping and cause a possible fire hazard.

It did seem strange as all new cars have a electric fuel pump maybe it was put there by lawyers to protect the company.

Ed

New cars have a crash (or a really big bump) activated fuel pump cut off switch.

[Normspeed]

Norm;

If the switch is activated by oil pressure how does the engine get fuel at start up time? I was led to believe one benefit of an electric fuel pump is instant priming of the carburetor after the engine has been sitting for a period of time. And the engine has no oil pressure if it is not running.

Seems like the article I read included a pushbutton that got the pump running for priming the motor, then when the oil pressure came up the pump continued to run. Seemed like a lot of trouble to me though.

[Don Coatney]

Ed' date='

As mentioned I didn't have the same type of pump Normspeed posted. Mine was the Bellows type. The instructions for that cutoff switch was as I mentioned.

That said, regardless of which pump used, I don't see how it's possible to hook up an electric switch to our cars. We don't have electric oil pressure gauges, they are mechanical. So, it seems one would also have to convert their gauges to electric gauges to hook up a fuel pump electric gauge to make the switch work.[/quote']

Norm;

Think about it for a moment. How does the stock brake light switch work on a P-15?

[Normspeed]

The switch I saw involved a tee fitting where the oil pressure line meets the block. They installed a pressure activated switch there (probably something like a hydraulic brake light switch) and routed the power to the pump through that, or possibly used a relay activated by that switch. So if the oil pressure drops, the power to the pump cuts off. This was not on a Mopar engine but I suppose it would work.

[Normspeed]

While we're on the subject, anyone know the details on fuel pressure gauges? I have one on my car. I noticed when I got it that inside the little hole on the back, where it screws to the fuel line fitting, the hole is threaded and there is a tiny slotted setscrew in there. On mine, the screw is loose enough that it doesn't necessarily stay at the same setting. I thought it might be a calibration setting for the gauge, but I've run it all the way in both directions with no change in the pressure reading. I've asked a number of folks including Chico, the guy that owns Mooneyes, (they sell a similar gauge) and no one seems to know why that little setscrew is there.