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mmagic
08-06-2013, 08:35 AM
Is there a best location for electric fuel pump ?

My current thought is on frame rail very very close to gas tank in area of rear axle. Then adding an extra wire to the new rear wiring harness to feed it. Logic for this location is just to avoid the clutter on frame rail forward and make for better access should it fail.

Where is fuel pump safety switch positioned on a 259? Does this require a relay?

PackardV8
08-06-2013, 09:57 AM
The best location for an electric fuel pump is inside the tank. That's where most OEMs locate them.

For outside the tank, your logic is correct, as close to the tank as possible and slightly below. Most get a Ford impact switch from the U-Pik and locate it inside the trunk, so the reset button is accessible.

jack vines

mmagic
08-06-2013, 10:20 AM
Ford impact switch is a new term for me. What does it look like and where is it located? I'm going to pick and U.Pull&Pay to scout PS and Steering parts shortly.

wittsend
08-06-2013, 11:16 AM
The impact switch is typically mounted in the trunk of just about any fuel injected Ford. Just remount it in a similar area where you removed it from the donor car. Wire it inline with the 12v+ of the fuel pump wiring. I've included a picture.
26434
This came out of my 1988 Turbo Coupe and is currently installed in my 1973 Turbo 2.3 Pinto wagon. Because of the large rear hatch I had to mount it off to the side. They pretty much all look alike. You may have to press the reset button after installation due to handling.

Tom

Mike Van Veghten
08-06-2013, 11:24 AM
mmagic wrote -
""Logic for this location is just to avoid the clutter on frame rail forward and make for better access should it fail.""

This comment isn't up to the actual reasoning though.

The reason for the location you mention, is that these pumps do not "pull" fuel very well, but they "push" the fuel very nicely.
So..this is the reason for being close and low is the reasoning for a close to the tank location. Insulate it well with rubber at all mounting points to help keep the sound from flowing thru the frame and body and messing with your easy touring attitude.
I mounted mine to a seperate piece of aluminum that's also rubber insulated from the frame. This setup (Carter pump) is a very quiet assembly. With the engine off, it can easily be heard, but as soon as the little 6 is started, it drowns out the pump sound.

Mike

mmagic
08-06-2013, 01:41 PM
Great insight and points. I'll do all.

SScopelli
08-06-2013, 02:29 PM
mmagic wrote -

The reason for the location you mention, is that these pumps do not "pull" fuel very well, but they "push" the fuel very nicely.
So..this is the reason for being close and low is the reasoning for a close to the tank location. Insulate it well with rubber at all mounting points to help keep the sound from flowing thru the frame and body and messing with your easy touring attitude.
I mounted mine to a seperate piece of aluminum that's also rubber insulated from the frame. This setup (Carter pump) is a very quiet assembly. With the engine off, it can easily be heard, but as soon as the little 6 is started, it drowns out the pump sound.

Mike

To Mike's point

http://i1286.photobucket.com/albums/a609/R2Whistler/Misc/DSCF3061_zpsa0c07752.jpg

The rubber mounts I bought at Granger.. This is the best pic I have, But the final install also use rubber hose to connect the lines to the pump as the pump sound resonated in the fuel lines and fuel line clamps..

Once the fuel goes in the tank it will siphon to the pump which for the Holley pumps is a requirement.

On final note.. On a lark, this place is really ope for easy access once the body is on..

JoeHall
08-07-2013, 08:55 AM
For many years & miles I have located them on the front gravel shield, next to the horn and never had a problem. I recently replaced a pump for a 56J guy that was mounted on the frame just above the rear axle. I have a 63GT, that the PO mounted a pump on the frame just behind the driver's door. So the pump will work from any of those locations.

However, it seems the frame mounted ones do not draw as well as easily as the ones next to the horn do. My theory as to why, is due to a siphoning effect. Sitting on level ground, I believe it is possible to siphon a tank dry at the front location (without a pump), maybe also on the frame behind the driver's door, but probably not at the rear axle. In other words, I believe the pump mounted on the gravel shield operates under less labor, and also gets the coolest air available.

In-tank pumps are supposedly best, for several reasons, some of which are debatable. Only drawback is, if it ever needs changed it is a PITA,. I cut a 6" X 6" trap door in the trunk floor of the 62GT, which has EFI with an in-tank pump, in case it ever fails.

mmagic
08-07-2013, 09:26 AM
Thanks.. I'll likely locate on the low part of frame between door and axle as far back as possible. I'm going by Granger this AM so I'll pick up some isolation blocks and I've got rubber gas line left from the Champ pump... then all I'll need is the pump, Ford trunk safety switch, wiring harness and the fuel line to arrive.

jclary
08-07-2013, 10:50 AM
The best location for an electric fuel pump is inside the tank. That's where most OEMs locate them....jack vines

Well Jack...I have a tremendous respect for your vast knowledge and opinions. However...here's where we part company on this one subject. I try not to buy-in on conspiracy theory stuff like UFO'S and the like. But this "in tank" fuel pump crap is one that boils my aging blood! At best...it is engineering malpractice! At worst...it is a diabolical immoral conspiracy to take advantage of a mechanically ignorant public and rob them of their hard earned money.

I have sold and worked on pumps of all kinds. I have also sold tools and supplies to manufacturers of fuel pumps. Pumps are built to certain tolerances with a built in "slip" (my term) engineered to allow them to pass some specified size solids (debris) and continue working. The problem I have with in tank pumps is that they have this tiny little "Pre-filter" screen/sock/strainer attached to the inlet of the pump. Supposedly this ten-cent piece of crap is there to keep junk out of your fuel system. Problem is...that ten-cent piece of crap will also clog up and shut off your $40,000 dollar vehicle at interstate speeds while an 18 wheeler is tailgating you at 80mph!:eek:

If you survive that little surprise...then comes the "tow-in" charges. The diagnostic charges...then the confiscatory obscene garage bill for dropping the tank and installing a completely new pump assembly:mad:...all over a ten-cent piece of sub-micron particulate filter! The pumps can and should at least be built to pass through tank debris that could just as easily be filtered down-stream by a external in-line filter. However, replacing fuel pumps for dealerships is a highly profitable "cash-cow." I would be willing to bet that over 80% of in-tank fuel pump failures are due to that little inlet filter and the pump itself is OK.

We've come a long way since the days of the gravity feed fuel tanks located at the firewall:ohmy:, where you had gallons of explosive fuel hovering a few inches above your lap:eek:. Modern closed loop electronic controlled fuel injection systems operate at much higher fuel pressure than our old rubber diaphragm mechanical pump engines...and in-tank location is great for the pump...but make that pre-filter a blasted strainer, not a show stopper! Good Grief!:QQ::mad:

(Not that I feel strong about this...Gee...now I need therapy!:()

mmagic
08-07-2013, 09:22 PM
Picked up two isolation mounts at Grainger today.... Now I have to get a pump before the fuel line arrives Monday.

Johnnywiffer
08-08-2013, 04:15 PM
Not long ago I had what I assumed to be a fuel pump problem in my 2000 Chrysler T&C, so I had it replaced. BAMS suggested that NEXT time, I just pound on the gas tank with a hammer (or whatever was at hand) and that MIGHT "repair" it. Haven't had another fuel pump problem since then and can't say I'm eager for one to occur.

But I DO have a pretty good sized hammer, at the ready, just in case.

John

SScopelli
08-09-2013, 03:41 AM
Picked up two isolation mounts at Grainger today.... Now I have to get a pump before the fuel line arrives Monday.

Here is what I used to wire up electric fuel pumps..

http://i1286.photobucket.com/albums/a609/R2Whistler/Misc/Fuel_Pump_Wireing_zps8238b51d.jpg

Most installs say to put +12v on the center pin of the Oil Pressure Switch. However, if your car has an Oil Light, the pressure switch, switches the negative to the light bulb in the instrument..

This oil pressure switch does both, light the Oil Light when pressure is below 5 psi and start the pump when oil psi is above 5 psi..

On the 312 relay, an active ground is what energizes the relay and the +12 is always present.

The 206 relay assist on starts to activate the pump when oil psi is bellow 5 psi and the key switch is energizing the starter..
During this time, it will provide the active ground signal to the 312 relay.

You can leave out the 206 relay, but you will have to rely on the fuel in the carb to start it.

You could add a momentary switch to provide the active ground signal to the 312 relay to prime the carb in lieu of the 206 relay as well..(Not pictured)

This diagram also shows the inertia switch in-line with the +12 volt wire to the electric fuel pump.

mmagic
08-09-2013, 07:56 AM
Thanks.. This is gold and should be added to Bob Johnstone's site. Planning on using new Stewart Warner 12V gauge set so I'm sure I'll need a second sender.

jclary
08-09-2013, 08:08 AM
Thanks.. This is gold and should be added to Bob Johnstone's site.

Great suggestion. and if someone is wanting to keep their six volt electrical system on pre-1956 models...does someone have part numbers for the required 6 volt pump and components? I have never done an electrical fuel pump installation and this would be great for anyone wanting to do it. Can't get any simpler than this...great post.:!:

SScopelli
08-09-2013, 12:40 PM
Great suggestion. and if someone is wanting to keep their six volt electrical system on pre-1956 models...does someone have part numbers for the required 6 volt pump and components? I have never done an electrical fuel pump installation and this would be great for anyone wanting to do it. Can't get any simpler than this...great post.:!:

I believe there is a list of electric fuel pumps listed on this forum and Bob's web page..

Search "best electric fuel pump"

As for the relays, they will work on 6v systems as I believe they will energize at 3v..

avantibngrant
08-09-2013, 01:01 PM
Not long ago I had what I assumed to be a fuel pump problem in my 2000 Chrysler T&C, so I had it replaced. BAMS suggested that NEXT time, I just pound on the gas tank with a hammer (or whatever was at hand) and that MIGHT "repair" it. Haven't had another fuel pump problem since then and can't say I'm eager for one to occur.

But I DO have a pretty good sized hammer, at the ready, just in case.

John
It has been said before "if you can't fix it with a hammer, it is most likely an electrical problem"

41 Frank
08-09-2013, 02:03 PM
I worked on these type of problems professionally for many years and I can assure you the problem will reoccur. Usually at a very inopportune time. Once this problem occurs it is best to get the in tank pump replaced as the pump was telling you the pump motor's brushes are about shot.


Not long ago I had what I assumed to be a fuel pump problem in my 2000 Chrysler T&C, so I had it replaced. BAMS suggested that NEXT time, I just pound on the gas tank with a hammer (or whatever was at hand) and that MIGHT "repair" it. Haven't had another fuel pump problem since then and can't say I'm eager for one to occur.

But I DO have a pretty good sized hammer, at the ready, just in case.

John

41 Frank
08-09-2013, 02:08 PM
The pump number you want is an Airtex EP-11 (6 volt) or equivalent. Their EP- 12 would be for 12 volt.

Great suggestion. and if someone is wanting to keep their six volt electrical system on pre-1956 models...does someone have part numbers for the required 6 volt pump and components? I have never done an electrical fuel pump installation and this would be great for anyone wanting to do it. Can't get any simpler than this...great post.:!:

mmagic
08-09-2013, 05:42 PM
After getting the pump and actually trying to locate an aft position, I've concluded there isn't a good location. Between wheel wells and e brake cables on a K car, I'm ending up above the axle... not good but about the only spot unless I go to the engine bay.

JoeHall
08-09-2013, 09:18 PM
After getting the pump and actually trying to locate an aft position, I've concluded there isn't a good location. Between wheel wells and e brake cables on a K car, I'm ending up above the axle... not good but about the only spot unless I go to the engine bay.
Are you trying to mount on the inboard side of the frame rail? My 63GT's is mounted on the outboard side, 6" behind the rear edge of the driver's door. Mine is an SI type, but I plan to swap it out for a "cube" type, and will probably leave it in the same location. You will have little, if any siphoning effect if mounted above the rear axle.

mmagic
08-09-2013, 09:33 PM
On the Speedster, the Hog trough extends from the bat wings to the rear wheel well on the outside of the frame.

JoeHall
08-09-2013, 09:46 PM
On the Speedster, the Hog trough extends from the bat wings to the rear wheel well on the outside of the frame.

Good point. I should know that, from looking at the underside of the 56J, ever since 1986 :)

Jersey2J
08-10-2013, 10:17 AM
We have a 6-volt positive system on our 1950 Champion. The electric pump is mounted close and low to the fuel tank, which pushes the fuel to the engine bay. One issue we had: if you do not have the correct current going to the pump it will push too little fuel and the car will die on you. I replaced a pump thinking it went bad when the issue was one to do with electrical current. We also installed a mechanical pump, and now use the electric pump on start-up and to avoid vapor lock.

Corley
08-10-2013, 10:40 AM
Well Jack...I have a tremendous respect for your vast knowledge and opinions. However...here's where we part company on this one subject. I try not to buy-in on conspiracy theory stuff like UFO'S and the like. But this "in tank" fuel pump crap is one that boils my aging blood! At best...it is engineering malpractice! At worst...it is a diabolical immoral conspiracy to take advantage of a mechanically ignorant public and rob them of their hard earned money.

I have sold and worked on pumps of all kinds. I have also sold tools and supplies to manufacturers of fuel pumps. Pumps are built to certain tolerances with a built in "slip" (my term) engineered to allow them to pass some specified size solids (debris) and continue working. The problem I have with in tank pumps is that they have this tiny little "Pre-filter" screen/sock/strainer attached to the inlet of the pump. Supposedly this ten-cent piece of crap is there to keep junk out of your fuel system. Problem is...that ten-cent piece of crap will also clog up and shut off your $40,000 dollar vehicle at interstate speeds while an 18 wheeler is tailgating you at 80mph!:eek:

If you survive that little surprise...then comes the "tow-in" charges. The diagnostic charges...then the confiscatory obscene garage bill for dropping the tank and installing a completely new pump assembly:mad:...all over a ten-cent piece of sub-micron particulate filter! The pumps can and should at least be built to pass through tank debris that could just as easily be filtered down-stream by a external in-line filter. However, replacing fuel pumps for dealerships is a highly profitable "cash-cow." I would be willing to bet that over 80% of in-tank fuel pump failures are due to that little inlet filter and the pump itself is OK.

We've come a long way since the days of the gravity feed fuel tanks located at the firewall:ohmy:, where you had gallons of explosive fuel hovering a few inches above your lap:eek:. Modern closed loop electronic controlled fuel injection systems operate at much higher fuel pressure than our old rubber diaphragm mechanical pump engines...and in-tank location is great for the pump...but make that pre-filter a blasted strainer, not a show stopper! Good Grief!:QQ::mad:

(Not that I feel strong about this...Gee...now I need therapy!:()

Really funny what turns some folks crank! I've replaced a lot of in-tank fuel pumps, but never ever found that in-tank strainer plugged or even close to plugged up. While in-tank pumps are a pain to replace, and only seem to go about 125K - 150k miles before the brushes give out, the fuel around them keeps them cool, and they never have a prime problem. Question: What do you put into your tank? I only put gas in mine. :D

jclary
08-10-2013, 12:19 PM
Really funny what turns some folks crank! I've replaced a lot of in-tank fuel pumps, but never ever found that in-tank strainer plugged or even close to plugged up. While in-tank pumps are a pain to replace, and only seem to go about 125K - 150k miles before the brushes give out, the fuel around them keeps them cool, and they never have a prime problem. Question: What do you put into your tank? I only put gas in mine. :D

Well Mr. Corley, the folks in Washington may be PERFEK...but in other parts of the country, I have watched the store clerk walk out to the manhole cover, on a windy, dusty day, flip it over, and then go over to a dirty wooden measuring stick lying in the dirt beside the building, shuffle back and stick that thing into the hole to check fuel level. There's all sorts of "hand-offs" from the time the stuff that becomes fuel for our vehicles until it gets to the nozzle of the gas pump. I know these systems have filters and procedures, but they are not infallible.

One of the cruel realities of the tiny debris that ends up in our filters, is that it often obtains the equivalent of "water-logged," like a piece of sunken wood in the bottom of a lake. Except in this case, it becomes "fuel-logged." As you bounce down the road, those little bits of debris get stirred up in the turbulence. As they float near the fuel pump inlet, the suction grabs them and holds them against the strainer inlet. Enough of that, and the fuel is choked off, engine stops. That's why, after a period of sitting, the stuff falls back to the bottom of the tank, and the engine will run as if nothing ever happened. Usually it runs again until enough of that garbage gets trapped again to shut you down. Either its like I said before, on the interstate while you are being tailgated, or when you are off in the boonies with no cell signal.:(

I had it to happen with a '79 Honda Accord I bought new. First time on that car was probably with little over 50,000 miles on the car. Later, I had it happen on a '95 Dodge Ram with over 100,000 miles. I have never been into the in tank pump on my (purchased new) '87 Nissan Hardbody King-cab truck, but it is on its third external fuel filter with over 334,000 miles.

The last time my former '95 Dodge Ram left me stranded, was up against a guard rail on the side of an interstate...by the time the Roll-Back pulled in my yard, enough of the debris had fallen off the in tank fuel pre-filter, the truck fired right up and I backed it off the wrecker under its own power. When I removed the pump from the tank...like you said, the pre-filter (although somewhat dirty and discolored) was not clogged. I powered up the pump on my work bench, and it ran fine. However, by that time, I had already purchased the new pump. I cleaned the tank, installed the new pump, and it was still running fine when I got rid of the truck.

I am not sure of all the engineering that goes into the design of our modern fuel systems, however, I just think that the pre-filters should be strainers that reasonably allow the more fine debris to flow through the pumps and then be filtered more thoroughly by a more accessible external filter. Apparently, that must be the case with my old Nissan truck...or I have been extremely lucky.:)

PlainBrownR2
08-10-2013, 05:22 PM
Between the whole lot of ya's, it should be noted, whether you have an in tank pump, or an external like mine. that the filter, strainer, or whatever that is between your tank and your fuel pump, is your first line of defense and should be cheap insurance against whatever sediment or contaminates are in your fuel that come from the underground tank. The same line of thinking also applies to the brass strainer(if yall still have it) in the inlet at your carburetor. I have found, especially after changing a Holley Black high pressure inline gerotor pump on my Lark, that there are two things that will kill a fuel pump. One is being subject to no fuel or load, and overheating. The other is being subject to fine grains of whatever from the fuel pump. The pump is designed with tolerances in mind to pump liquid, not liquid and everything else. The sediments in the fuel can act like sandpaper on the vanes in the gerotor, and effectively destroying them in a very short order. In short, I'd rather change a disposable, dirty, clogged fuel filter, than have to spring for replacing an expensive filter and pump assembly, because the pump was destroyed inside. :)

Corley
08-10-2013, 10:40 PM
John,

I think what you feel is a clogged in tank filter, is actually a pump failure. When the brushes in the pumps go bad, they usually go to an intermittent run situation for a while before they pack it in for good. Sometimes you can bang on the tank and get them going again, and it may work for a bit longer. If you have it happen again, have someone go stand by the gas tank and listen for the pump, then turn the key on a few times. It should run for a few seconds each time you turn the key on. If it doesn't make that buzzing/humming sound, it isn't the pre filter, it is an almost shot pump. Put her on the roll back, and chances are it'll come alive again, but it's about to fail for good, so get that new pump on order. Forget the pre-strainer, as I said, I've never seen one be the problem.

JoeHall
08-10-2013, 11:31 PM
John,

I think what you feel is a clogged in tank filter, is actually a pump failure. When the brushes in the pumps go bad, they usually go to an intermittent run situation for a while before they pack it in for good. Sometimes you can bang on the tank and get them going again, and it may work for a bit longer. If you have it happen again, have someone go stand by the gas tank and listen for the pump, then turn the key on a few times. It should run for a few seconds each time you turn the key on. If it doesn't make that buzzing/humming sound, it isn't the pre filter, it is an almost shot pump. Put her on the roll back, and chances are it'll come alive again, but it's about to fail for good, so get that new pump on order. Forget the pre-strainer, as I said, I've never seen one be the problem.

I agree, the sock is huge, and if it were to fail, it would likely not be all at once. It would probably run worse & worse as it became increasingly clogged. If there's enough sediment in the tank to clog that sock, the tank needs to be dropped and cleaned anyway.

If I had it to do over again with the EFI, I'd go with an in line pump, just for ease of changing it if it ever failed. But the in tank pump has several benefits, as mentioned before, so I guess its six of one & half dozen of the other.

Nox
08-11-2013, 04:53 PM
I've put mine in the right front body-mount, maby I'll be sorry later...26572