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GrumpyOne
06-05-2015, 09:48 PM
I need a simple source to power an electric fuel pump used as an auxiliary. (pump is located on rear frame forward of the gas tank)

Any and all suggestions greatly appreciated.

TIA

JT

Corvanti
06-05-2015, 11:01 PM
i can't think of any reason not to run it from the battery or a power source in the fuse block. is it going into a 12V neg ground Studebaker? are you going to use this in addition to the mechanical fuel pump or on its own?

when i get a-round-tuit, i'm going to add one on the '51 - 6V pos. ground.

i would also suggest a switch to turn on-off under the dash and a gravity switch near the pump just in case there's a bad crash - flipover - etc. to turn it off and not pump gas into a bad situation...

Edit: i'm quite tired and sick - didn't see it's a '56, so nevermind some of the above questions...

GrumpyOne
06-05-2015, 11:20 PM
I think that I posted to the wrong thread and really should be in the Tech area. I'm going to repost there.

Thanks,

JT

GrumpyOne
06-05-2015, 11:24 PM
I would like to supply 12 volts to a frame mounted electric fuel pump and was wondering if any of the terminals on the voltage regulator become live when the key is in the "IGN" position?

Any info or suggestions greatly appreciated..

TIA

JT

showbizkid
06-06-2015, 12:26 AM
What year is your car? I can only speak to Larks :) Having said that...

If your car does not have Overdrive, there is a red lead in the wiring pigtail to the distributor that terminates in a female bayonet connector to nowhere. This is part of the the OD solenoid energizing circuit, and it will be live as soon as you turn on the ignition :)

showbizkid
06-06-2015, 12:35 AM
Merged both threads to one :)

Anyone who posts to the wrong area, please let your friendly Mod Squad know and we will gladly move it for you!

garrilla
06-06-2015, 07:02 AM
You should consider using a relay with the #30 pole fused from the battery. Then a wire from an ignition source run to #86 pole to activate the pump. #85 pole can be tied into an oil pressure switch to kill the pump if the engine is off. Go to http://www.madelectrical.com/index.shtml is an excellent source for wiring information.

Michael J Hawk
06-06-2015, 07:18 AM
I've been wondering what that red wire was for. Came in handy for the electric choke.

wlfrench
06-06-2015, 10:44 AM
Why do you want an electric fuel pump?

showbizkid
06-06-2015, 11:25 AM
I've been wondering what that red wire was for. Came in handy for the electric choke.

Yeah, I used it for that for a while too!

DEEPNHOCK
06-06-2015, 09:11 PM
Fuel pumps should always be run with a relay...to improve switch life (whether it be a pressure switch, or a toggle switch).
A good idea is to incorporate an oil pressure switch, so the fuel pump will not run if the engine quits (ie: accident).
In the old days, a Vega switch worked well. Betcha there are a few good choices at Speedway, or Summit.
A manual override push button switch would be good to 'prime' the engine at start up, or when the first sign of vapor lock rears its head.
I'll let the experts chime in here....

Michael J Hawk
06-06-2015, 10:35 PM
An oil pressure switch is always recommended in the installation.

TWChamp
06-07-2015, 06:21 AM
I use an aligator clip and just clip my pump wire to the coil power feed, which would be the negative post on my 50 Champion.

garrilla
06-07-2015, 08:11 PM
The recommended oil pressure switch is AC Delco G1809 or GM3986857. This is a 3 pole switch that is wired to an ignition source, the starter circuit and to pole 86 on the relay. This switch will allow the fuel pump to run when cranking over engine. Pole 87 goes to the fuel pump, pole 87a is not used.

GrumpyOne
06-15-2015, 10:20 PM
What year is your car? I can only speak to Larks :) Having said that...

If your car does not have Overdrive, there is a red lead in the wiring pigtail to the distributor that terminates in a female bayonet connector to nowhere. This is part of the the OD solenoid energizing circuit, and it will be live as soon as you turn on the ignition :)


'56 Power Hawk... I ended up hooking it up to the ignition high side of the resistor and all seems to be working OK. Will be taking it out for a longer test drive this weekend. Thanks!

GrumpyOne
06-15-2015, 10:26 PM
Fuel pumps should always be run with a relay...to improve switch life (whether it be a pressure switch, or a toggle switch).
A good idea is to incorporate an oil pressure switch, so the fuel pump will not run if the engine quits (ie: accident).
In the old days, a Vega switch worked well. Betcha there are a few good choices at Speedway, or Summit.
A manual override push button switch would be good to 'prime' the engine at start up, or when the first sign of vapor lock rears its head.
I'll let the experts chime in here....

All great ideas especially for the prime... Thanks Mr. "J"