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Discussion Starter #1
I'm in the process of installing a 4BT into a 92 F150 4x4. It's coming along, thanks to many hours spent on this forum! I stumbled on 4BT4ME's photos and diagram concerning the "pressure regulator" he built for his truck. I have a couple of questions, if anyone has any insight:

In the photo, the "T" on top - I'm assuming that is the return line from the engine into one side of "T" and the other side of "T" goes to the tanks? Is it plumbed into (T'd) into the top of the "depressure tank" to allow excess fuel, if accumulated into the "DP" tank to escape down the return line?

Would anyone have any idea what this setup would drop fuel pressure to?

This setup would help me out if anyone could let me know if they've ran this setup successfully. I have high pressure pumps and it would just save all the hassle of doing it now. If I ever lost an internal high pressure pump, then I would just disable the pumps and run pickup lines, etc.

Below are 4BT4ME's photos from his original posts:

http://img178.imageshack.us/my.php?image=dscf1143pk3.jpg

http://www.4btswaps.com/forum/showthread.php?t=242&page=2&highlight=4bt4me (scroll halfway down the page or so to see diagram)

Thanks a bunch :beer:
 

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No need to do all that work , more to go wrong and look odd.The pump in tank just needs removed and gut the parts out or remove all together and just fun you supply and return line .


More than one way to do it ,it just doesn't look good but that's just me.

Scott
 

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When I did my 1989 f150 I just removed the the in-tank pump and the pump on the frame. I ran a new fuel and return lines. I would be nice to use the electric pumps so you don't have to take the tank off (to remove the pump) and you could still utilize both tanks. I think averagef250 had a solution too the high pressure problem. I think he ran the fuel through a transmission filter or something. I would look into this method if I were to do it over.
 

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Discussion Starter #4
Scott: To me, building a small tank, if it would work, and doing some minor plumbing is much easier than dropping both tanks and reconfiguring a selector valve (to allow both tanks to be used) and also running all new fuel line. But that's just me. I personally do not think it would look that bad having the tank on the inner fender, if it was done right. I do see your point, however.

Cornfeed: Do you know what average250 did with his setup, or how it worked? I haven't been able to stumble on that topic in the forum.

All: I'm a little rusty when it comes to the fuel setup in the 92 F150 (302EFI). I see no pump on inside of drivers frame rail, and no selector valve on frame rail (like older (or other) trucks had or have). Therefore, I'm assuming that, when the tank selector switch is used on the dash, that power is transferred from one intank pump to the other (as well as the sending units). Can anyone give me some insight on this? My concern is this: if I drop tanks and disable pumps, which selector valve should I buy to use on the frame rail to allow me to use both tanks? I think it was a 6 way, electric servo type thing that was used on some of the late 70's Fords, and I guess that would work but I haven't priced one. Essentially, I want to run both tanks, have both gauges work, and can run new fuel line (which I think would be easier than using existing "spagetti) fuel line...

My tech skills in this area are not quite up to par!

Oh, and thanks again. Found this forum months ago and should have started posting earlier. However, didn't want to ask questions that have already been resolved on other threads...

Wayne
 

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The EFI F-series trucks use two different fuel systems- The 87-89 trucks use a low pressure pump in each tank with an HP pump on the DS frame rail. The 90-97 trucks use just a HP pump in each tank.

There is absolutely no need to gut the tanks or build some super complex regulating contraption. If you get into gutting the tanks you then have to reinvent the wheel for the fuel line return and add a switching valve. Sounds pretty rediculous to me.

When you gut the Ford gas engine and you cut the fuel lines off at the fuel rail you're left with a pressure and return line set hanging in the engine bay. I flop the lines down on the driver's side frame rail and install an adapter for running bypass filtration on an automatic tranny cooler line. All this adapter does is connect the pressure line directly to the return and it has an orifice hole between them. On the pressure side of the orifice you connect the engine feed and on the return side of the orifice you connect the fuel return line from the engine. Then make a small bracket and mount the adapter to the engine frame crossmember and it looks nice and pretty and works like a champ.

The last thing you have to do is open up the relay box. I use the old EEC relay to send power to the injection pump solenoid and rewire the fuel pump relay to be triggered by the EEC relay instead of the EEC (since the EEC won't work anymore). This means your fuel pump runs any time the key's in the on position, but it seams to work fine.
 

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Discussion Starter #6
There is absolutely no need to gut the tanks or build some super complex regulating contraption. If you get into gutting the tanks you then have to reinvent the wheel for the fuel line return and add a switching valve. Sounds pretty rediculous to me.

" and install an adapter for running bypass filtration on an automatic tranny cooler line. All this adapter does is connect the pressure line directly to the return and it has an orifice hole between them. On the pressure side of the orifice you connect the engine feed and on the return side of the orifice you connect the fuel return line from the engine.

The last thing you have to do is open up the relay box. I use the old EEC relay to send power to the injection pump solenoid and rewire the fuel pump relay to be triggered by the EEC relay instead of the EEC (since the EEC won't work anymore). This means your fuel pump runs any time the key's in the on position, but it seams to work fine.
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Thanks alot Dustin. Just what I needed, someone thinking along the same lines as myself! Couldn't agree with you more about "reinventing the wheel".

A couple of follow-up questions: (bear with me, my knowledge of autos is very minimal)
On the "adapter for running bypass filtration", do you use a general item or one for a specific application. Could you give me a ballpark figure for the cost? (I just need to know what to ask for at the auto parts store...)

On the relays: You're saying: use the old EEC relay to run the injector pump and run the intank pump relay off of the old EEC relay also? ...because the fuel pump relay used to be triggered by the EEC? I may sound like a dummy, but I couldn't quite get what you were saying. I realize the EEC won't work and isn't needed, but can you explain exactly what goes where?

Thanks and I appreciate your help and patience. I've overhauled engines and done conversions before, but not on this new of a pickup so the electrical is a bit confusing...

Oh, and one other unrelated thing: I bought a vacuum pump/PS pump from a 6bt. Just to make sure, because I haven't been able to find the basic info. on the forum... closest to the timing gear cover, there is a fitting and a nipple. The fitting is the oil feed for vac pump (from oil port right above on side of block). The nipple is the vacuum line, right? The reason I ask is because the 4bt had the vac pump mounted by valve cover, drivers side, and it had an oil return line also. The 6bt pump doesn't have an oil return line? It must not, because I don't see any other nipple except one and that should be the vac. outlet. Please correct me if I'm wrong. On the PS side, theres one fitting and two nipples. It's my understanding that's the pressure and two returns, and T'ing the returns together is fine (unless you have hydroboost and need the other return for that).

Thanks again, Wayne
 

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WAY more than what is needed- too complicated, plus you have to rely on very expensive in-tank pumps. The Ford pumps aren't as costly, but are notorious for having problems. Some of the main points of a diesel conversion is reliability and simplicity. For our Durango, I'm just gutting the old sender/pump assembly and putting in a simple pickup tube. A replacement pump for my vehicle is $290. Thanks, but I'll avoid that.

As for the dual tanks, mineitnow is exactly right. A simple, and fairly inexpensive, valve can be installed to be able to use both tanks with the diesel.

Jim
 

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I say it's overkill to drop the tanks to gut them. If the darn fuel pump ever dies on you THEN go through the huge headache of dropping the tank and remove the pump. Otherwise just leave it alone. The pumps are not that problematic. I don't know about you guys, but I really like electric FP's. OOPS! got a tankful of gas? No problem, pull the fuel line off, stuff it in a bucket and turn the key on.

Use the EEC relay to power the injection pump and activate the fuel pump relay. You don't need to rewire much of anything. You're just taking the power leaving the EEC relay to feed the IP solenoid and using it to activate the existing FP relay. They're right next to one another in the relay box on the fender.
 

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got a tankful of gas? No problem, pull the fuel line off, stuff it in a bucket and turn the key on.
Exactly my method for dropping a fuel tank with an intake pump. You may have to hot wire the pump, but it is still much easier than dropping a full tank of fuel. I presonally don't find dropping an empty fuel tank difficult, unless you are speaking of a late model f-body.

Personally, I would pull the tank and replace the pump with a pickup.

Mike
 

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We just did this with a late 80's Land Cruiser we are installing a diesel into. In the end it was maybe an hour total to drain and drop the tank and remove the pump. We installed a new metal collector (made out of an large diameter brake line tube) for the fuel in place of the pump. It was 110% worht it to take the time to drop the tank in my opinion.

I have messed around with choking down high pressure pumps to low PSI and it has never worked for me long term. The electric high pressure pumps for me only seem to work well in their original OEM application or similar.
 

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Discussion Starter #13
Yea, thanks. I should have seen that before.
 

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Discussion Starter #14
In regards to dieseldurango.
 

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I have messed around with choking down high pressure pumps to low PSI and it has never worked for me long term.
That is only with "dead head" style fuel pressure regulators.

If you use a full bypass regulator (Aeromotive or Mallory) then it is VERY easy to get down to 5 psi.
 

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if you use a bypass style regulator, and hook the return to your exisiting retun line, what do you do about the return line comming off of the back of the ve pump? I would assume that you cannot just tee it into the other return can you? I mean that would pressureize the return of the injection pump right?
 

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Cut the pump off the front in-tank module so you still have the level sender and put on a fuel pick up. keep your rear in-tank pump but route the pressure line into the front filler tube and use it to transfer fuel from the rear to the front when it gets low. Fuel return from engine goes into front tank. No selector valves to mess around with. I wired in a red light to remind me when I am transferring fuel to the front tank. Worst case if the rear pump fails I'm down to one tank, no big deal.
 

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Just in response to the system I originally built that was cited, it never failed... but that doesn't mean it was right. That dopey system was just an easy way to get the truck going, and will be getting changed at some point in the not so distant future!
 

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This may be of some help. I used the XJ tank on my XJ since I had it already. You can most likely source an XJ tank for near free. The bypass setup is very easy to do and the stock guts can mostly be kept. I not sure on fitment or if the level sender with all work, but the tank is VERY easy to use for these kinda swaps (in an XJ at least).
 
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