Electric fuel pump conversion project

7173Mustangs.com

Help Support 7173Mustangs.com:

Jackwagon3

Member
Joined
Dec 3, 2021
Messages
14
Reaction score
10
Location
Richmond Ky
So I'm installing a holley blue electric fuel pump and have a question about the return line I'm adding off my pressure regulator. When I dropped the tank I noticed there is a vent at the top of the tank that has been plugged off for a long time somewhere in the engine compartment. Can I use the hole that was for the vent and use it for my return fuel line? I was going cut a hole on the top of the tank to put in a AN 90 bung and run the return in there. Can't I just use a round piece of metal the same size as the vent valve? That way I can disconnect it quick and easy just like the sending unit?
 
Joined
Aug 14, 2014
Messages
4,016
Reaction score
1,052
Location
Madison, WI
My Car
1971 M-Code Mach 1 w/408C stroker
I use a similar setup but my electric pump is a surge pump type that does not return that more fuel. I don't see any issues with using that hole except for venting. Just be aware that if you use the stock cap, the barbed nipple has a very small hole since it is used for venting. Therefore, you will need to replace this nipple or drill the inside. I ended up using an old sending unit since the hole is of the same size. I used the sending unit without the float, just to use the tubing. Another thing that you will have to figure out is how to vent the tank. In my case it vents through the cap so make sure you have a cap that allows air flow in both directions, or have a cracked gasket on the gas cap:unsure:.
 
Joined
Dec 14, 2017
Messages
438
Reaction score
514
Location
Erie, Pennsylvania
My Car
72 Mach 1 Q code. Now: 427C Titus, CHI top end, TKO 600, 4 wheel discs
So I'm installing a holley blue electric fuel pump and have a question about the return line I'm adding off my pressure regulator. When I dropped the tank I noticed there is a vent at the top of the tank that has been plugged off for a long time somewhere in the engine compartment. Can I use the hole that was for the vent and use it for my return fuel line? I was going cut a hole on the top of the tank to put in a AN 90 bung and run the return in there. Can't I just use a round piece of metal the same size as the vent valve? That way I can disconnect it quick and easy just like the sending unit?
This all-in-1 return line product will simplify your return line project Jackwagon:

RobbMc Performance​

Fuel Pickup – 1/2" Sending Unit, PN 1101​

Applications:​

  • 1971-73 Ford Mustang
  • 1971-73 Cougar
 

Attachments

  • 1101_fordsend_4x.jpg
    1101_fordsend_4x.jpg
    45 KB · Views: 1

Mister 4x4

Too Big to Sneak
Staff member
Administrator
Moderator
Joined
Aug 12, 2010
Messages
8,252
Reaction score
559
Location
San Angelo, Texas
My Car
1971 Mustang Mach 1
That Holley Blue is going to be LOUD! I had a Holley Black on mine, and while it worked really well, it was super loud (as most rotary vane pumps are). I switched to a Holley Mighty Mite, and it's a LOT quieter. It's Gerotor-style (worm-gear, basically).

Here's a quick vid of mine running the Holley Black. You can hear it just before the engine starts (5-6 sec point).

 

AcesArneson

Well-known member
Joined
Aug 17, 2019
Messages
112
Reaction score
39
Location
Fort Mac, Alberta
My Car
1973 Mustang convertible H code 351C-2V Playmate Pink
So I'm installing a holley blue electric fuel pump and have a question about the return line I'm adding off my pressure regulator. When I dropped the tank I noticed there is a vent at the top of the tank that has been plugged off for a long time somewhere in the engine compartment. Can I use the hole that was for the vent and use it for my return fuel line? I was going cut a hole on the top of the tank to put in a AN 90 bung and run the return in there. Can't I just use a round piece of metal the same size as the vent valve? That way I can disconnect it quick and easy just like the sending unit?
I think you are just looking for this.
 

Jackwagon3

Member
Joined
Dec 3, 2021
Messages
14
Reaction score
10
Location
Richmond Ky
I like the idea of the sending unit with the return line in it and ready to go. Think that'll be the route I go. Or I'll make a round plate the same size as the vent valve and drill my hole in that for my return.
So this blue pump is going to be louder than I'm used to and I'm fine with that. But if it's too noisy for my liking, what other pumps have you guys been using that are less noisy?
 
Joined
Dec 14, 2017
Messages
438
Reaction score
514
Location
Erie, Pennsylvania
My Car
72 Mach 1 Q code. Now: 427C Titus, CHI top end, TKO 600, 4 wheel discs
I've run many, many different electric pumps, and as stated rotor/vane types make some noise (such as Holley Red, Blue and Black). Three things will quiet them down a lot though:
1. Insulate attachment points WELL with rubber gaskets/washers.
2. Don't "dead head" them (use a return line-as you are).
3. Use a dedicated fused power feed (10-12 ga) from the battery +terminal or hot side of starter relay.
But if it's still too loud, this similar rated Holley HP125 is very quiet and mounts/plumbs the same way as the Red, Blue & Black pump:
ON A SAFETY NOTE: Consider an in-cabin power cut-off switch and/or a low oil pressure auto kill switch for the pump.
 

Attachments

  • hly-12-125_xl.jpg
    hly-12-125_xl.jpg
    67.1 KB · Views: 0
Top