euclid
SILVER Star
I need to run an external fuel pump for my new brown davis long range tank. How do I figgure out what fuel pump to run? Stock 3FE
TIA
TIA
3fe external fuel pump
- Thread starter euclid
- Start date
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Try a search, I remember something about using the pump from a Ford F-250 in a past thread.
Tony
Tony
Shouldn't be too tough there. I believe the stock system ran at ~ 40 ish psi. most of the pressure is controlled by the return line anyway.
Honestly it is not that tough to make your own sub fuel pump with the stock one tho. What is the mount like? Does it have a ~2" hole in the top of the tank?
Honestly it is not that tough to make your own sub fuel pump with the stock one tho. What is the mount like? Does it have a ~2" hole in the top of the tank?
matt.mcinnes
2F-ETI
Cross posting the cross post 
IH8MUD Forums - View Single Post - 3fe in a 40, what fuel pump? cross post
IH8MUD Forums - View Single Post - 3fe in a 40, what fuel pump? cross post
Greg - I saw your post on my 3FE40 build. I've been running that MSD pump for over a year with no problems. Just remember that Randy had put in a adjustable Fuel pressure regulator and capped one end of my injector fuel rail so the pressure would stay up. -Mark
euclid
SILVER Star
- Thread starter
- #10
I don't have the fab skills to modify the tank to drop the internal pump in.
K. I'm hoping I get the truck running with the pump I got from the local hot rod shop.
Tank is in, all set to go. No power to the pump. Fuse is good. I'm backing up in the wiring now. When I jump the B+ and FP like the book says I get nothing. The ecm must be looking for some condition to be met to fire the pump. Searching now....
euclid
SILVER Star
- Thread starter
- #11
EFI Main relay has no continuity between 1 and 3, fails that test. It opens and closes with 12V, pases that test. Truck was running fine. I'm wondering if the new pump tried to pull too much voltage when I first fired it up and blew that relay. Fuse is fine though.
Mark
What happens to the fuel not used by the injectors if one end of the rail has been capped? The stock system regulates pressure by releasing the excess back to the tank (through a pressure reglulator) with a return line, I take it this is the line that has been capped. Does your pump operate differently? It sounds like your regulator is before the rail not after like the stock system. Just looking for info as obviously your system works and someday I plan on running an external pump.
Tony
Greg
I would think that the new pump would blow a fuse rather than a relay, not to say the relay was any good to start with. My understanding is that the relay doesn't take the load only allows it to happen. (Anyone with more knowledge of relays please correct me if I am wrong).
The hard part to compare is the amp draw of both pumps. Does the new pump require the same amount of amps to run?. Does it have the same number of wires? Is the new pump adjustable for PSI? This may be giving the computer bad info but I can't be sure.
Tony
I would think that the new pump would blow a fuse rather than a relay, not to say the relay was any good to start with. My understanding is that the relay doesn't take the load only allows it to happen. (Anyone with more knowledge of relays please correct me if I am wrong).
The hard part to compare is the amp draw of both pumps. Does the new pump require the same amount of amps to run?. Does it have the same number of wires? Is the new pump adjustable for PSI? This may be giving the computer bad info but I can't be sure.
Tony
Fuel pumps don't draw that much electricity. I doubt that you could fry the relay, I am not understanding the no continuity between 1 and 3 if the relay is opening and closing with 12v.
IIRC the engine actually has to be turning over to put power to that relay. I thought it was odd at the time as most FI systems will trigger the fuel pump for a couple of seconds to prime the system.
BTW, that whoe concept of plugging off the fuel injection line seems really odd to me as well..
euclid
SILVER Star
- Thread starter
- #15
The book gives 3 tests for the efi main relay, mine fails 1 of the 3.
Tested the cirquit opening relay, it pases all four tests.
Ran an extra ground wire from the pump to the frame. No change. Double checked fuses and cirquit breakers.
Im stumped. New relay tomorrow, since i dont know what else to try.
Moby
GOLD Star
Yeah, I've heard of converting new style "deadhead" EFI fuel systems to a return line but never the other way around. I'm not sure why OEMs have gone to the deadhead style in recent years. I'd be very interested in hearing more if anyone has insight into the pros/cons of deadhead vs. return line designs for EFI fuel systems.
I use a external FPR routed back to the tank.. If my memory is correct - we first tried a return line from the injector rail, but the pressure was not enough to fire thru the injectors, so we ended up capping one end of the rail off. Randy....chime in here..
It was a volume issue. When the truck was running on the OLD PUMP under idle or slight load it did fine. But as soon as you got after it it would starve and cause the truck to buck like a bull. I run the MSD 2555 on the vortecs and it was plenty for the 3FE. I thought it would work better and be easier to trouble shoot in the future.
It is regulated with the aeromotive regulator in the background. The regulator has a return line on it. Very simple and easy to trouble shoot. If you need the PN# for the regulator it is: aeromotive 13109
Aeromotive 13109 - Aeromotive A1000-6 Injected Bypass Regulators - summitracing.com
The regulator and the pump will run around 200.00 clams.
If you want the hose to run the line like Mark's it is summit # SUM-PUMKIT1
Gauge: SUM-800199 0-100 psi
Answer to the Pro's and Con's I think a dead head system allows for a more consistent rail pressure without overworking the pump. Here is a pic of Mark's current set up as it is today.
RT Customs Irving Texas- powered by SmugMug
Sorry at work and it doesn't allow uploading but you will see the return line capped off on the rail in one pic of the engine, as well as the other set up retaining the return line that I didn't like.
It is regulated with the aeromotive regulator in the background. The regulator has a return line on it. Very simple and easy to trouble shoot. If you need the PN# for the regulator it is: aeromotive 13109
Aeromotive 13109 - Aeromotive A1000-6 Injected Bypass Regulators - summitracing.com
The regulator and the pump will run around 200.00 clams.
If you want the hose to run the line like Mark's it is summit # SUM-PUMKIT1
Gauge: SUM-800199 0-100 psi
Answer to the Pro's and Con's I think a dead head system allows for a more consistent rail pressure without overworking the pump. Here is a pic of Mark's current set up as it is today.
RT Customs Irving Texas- powered by SmugMug
Sorry at work and it doesn't allow uploading but you will see the return line capped off on the rail in one pic of the engine, as well as the other set up retaining the return line that I didn't like.
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