Where do I grab power for the electric fuel pump?

[67Survivor!]

My '67 GTX had an electric fuel pump when I bought it. It's a Red Holley and is EXTREMELY loud. That's one issue. Whomever installed it wired it so that it's powered on any key position except off. Shouldn't it only get power from ignition on? If so, where can I get ignition on power under the hood? Does power need to come from the fuse box?

 

[Dave6T4]

The Run side of your ballast resistor. Key-on 12V. It might be good to wire in a 20 A fuse to that circuit.

 

[67Survivor!]

Perfect!
Thanks!

 

[65hemi]

My electric fuel pump is connected directly to the battery via a relay activated in the run position of the key. Connect the relay on the ballast like Dave said.

 

[topside]

I like to have a switch for electric fuel pumps.

 

[67Survivor!]

I have a switch mounted under the dash.

 

[kiwigtx]

The Run side of your ballast resistor. Key-on 12V. It might be good to wire in a 20 A fuse to that circuit.

Doing it that way, you SHOULD only use that circuit to supply a relay coil......take the actual main load from a different source, like from the alternator or battery - fused of course.

 

[72RoadrunnerGTX]

Draw power from the alternator side of the ammeter only, if running an ammeter. Agree, run a relay, recommend running an oil pressure cut-off switch as well. Kills the pump in the event of an engine stall also provides pump voltage while cranking ign1 does not. Monetary priming button optional.

 

[Aron Gleason]

I run mine through a relay, then to a toggle switch. And the main power wire is ran to a 12v key on power source at the fuse box.

 

[Nacho-RT74]

My electric fuel pump is connected directly to the battery via a relay activated in the run position of the key. Connect the relay on the ballast like Dave said.

If you still have an operative ammeter, use the batt as a source is not correct. Use alt post or any other buss/junction on alt side… between amm and alt.

 

[MoparLeo]

The low oil pressure switch is a great way to help prevent engine damage. No/low oil pressure, no fuel.

Draw power from the alternator side of the ammeter only, if running an ammeter. Agree, run a relay, recommend running an oil pressure cut-off switch as well. Kills the pump in the event of an engine stall also provides pump voltage while cranking ign1 does not. Monetary priming button optional.
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View attachment 1584559

 

[Thunderlugs]

You might want to install an inertia cut off switch while you're at it...in the event of an unfortunate occurrence.

 

[BB BELLA]

install a pressure switch at oil pressure sender! wire the pump to run in key start position and take power from sender when switch closes it will only keep running sensing oil pressure!

 

[BB BELLA]

if your interested in doing this way [the right way imo} here's mercruiser part numbers
sender switch 805024
tee if you need to tie senders together 28624
extension if needed for sender space, 805059
you may be able to locate this stuff elsewhere,but this is what i use!

 

[Geoff 2]

Post #2. Nope, do NOT connect the pump to the bal res. An inductive ign system needs all the voltage it can get to produce as much spark energy as possible. Connecting the pump to the bal res will reduce voltage to the ign coil.
What you CAN do is use a 30 amp Bosch relay [ a good idea ], & connect the relay coil to the bal res. It only draws about 1/6 amp, compared to several amps that the pump will draw. Connect the pump directly to the bat + terminal or alt stud, which ever is more convenient, with an inline fuse between pump & terminal.

 

[WileERobby]

It's a Red Holley and is EXTREMELY loud.

Consider a Holley Gerotor pump. A little expensive, but much quieter.

 

[Davefinan]

My electric fuel pump was loud also. I solved it somewhat with using old computer mouse pad material as an isolator/insulator. It cut the noise by more than half. I created a separate circuit for it from the fuse block ( fused) and used an inertia switch . 10 gauge wire.

 

[67Survivor!]

My electric fuel pump was loud also. I solved it somewhat with using old computer mouse pad material as an isolator/insulator. It cut the noise by more than half. I created a separate circuit for it from the fuse block ( fused) and used an inertia switch . 10 gauge wire.

No issues w/heat build-up?

 

[Geoff 2]

If you don't to be stranded at the side of the road, use a Carter 4594 [ or 460X depending on the expected HP ]. They last forever, & are quieter than the Holley pumps....

 

[BB BELLA]

agreed, the carters are quiet and longevity is unrivaled, i still run 2 from 1981 feeding my 225 merc outboards at 7000rpm so volume isn't an issue and no regulator required! running mixed gas through them probably helped with life span!