got some fuel questions

[crzybil87]

ok so im doing a cummins swap into my truck in the spring, and i need help figuring out the in tank senders.. im gonna re do from the motor back to the tanks, i guess one of my questions is are the diesel tank units ( from an early ford diesel) the same as my gas ones any help would be cool

 

[89PSD]

yup the diesel one will work on a gasoline tank. 97 and under powerstrokes will work for you.
you could get a aftermarket tank sump that you bolt onto the bottom tank... if your going for more then 600+hp then it would be something to look into. hellman machining makes one.

 

[crzybil87]

im gonna shoot for 450 so i should be good without a sump but ill look into it, could you think of anything i should change while i do this i plan to redo all the fuel lines and get rid of the pumps and in line filters foe the diesel set up

 

[flareside_thunder]

You'll also need the plug to fit those PSD sending units as the Gen 8 and Gen 9 sending unit plugs are different. Don't even bother looking for a sending unit from an IDI.....

 

[crzybil87]

youre talking about the electrical connection right?

 

[Fellro]

Which year truck are you doing it to? If you are doing it to the 87, then you could use the intank pump if you choose, have heard of some doing that. Otherwise, you could take the pump out, then just run a pipe where the pump was, and then use a hose to get to the bottom of the tank. I notched out the bottom so it could not be closed off by the bottom of the tank. When I did the 92, I used IDI senders since the original was a plastic pump module, but the 87 is not. I did get used units, as they have gotten tricky to find.

 

[flareside_thunder]

Yes, the electrical connection. Alot of guys get a brass Tee and stick it in the end of the hose right up against the bottom of the tanks as well. it weights it down and keep the hose from collapsing under suction. I see no problem with using the factory gas senders as long as you have an adjustable fuel pressure regulator inline.

 

[crzybil87]

well the cummins im using is a 92' and my trucks an 89' i was told i could do that, just use a hose to get to the bottom of the tank, some kid said to just break the plastic part off my sending units i have now, and others have told me to use the diesel units, im trying to get peoples opinions on this so i could get an idea of how to do it

 

[crzybil87]

yea while i was dealing with the fuel i was gonna put a pressure regulator on the fire wall somewhere in the system along with a fuel pressure gauge

 

[Fellro]

Yes, the electrical connection. Alot of guys get a brass Tee and stick it in the end of the hose right up against the bottom of the tanks as well. it weights it down and keep the hose from collapsing under suction. I see no problem with using the factory gas senders as long as you have an adjustable fuel pressure regulator inline.

You mean factory pump? Sender has nothing to do with pressure...

well the cummins im using is a 92' and my trucks an 89' i was told i could do that, just use a hose to get to the bottom of the tank, some kid said to just break the plastic part off my sending units i have now, and others have told me to use the diesel units, im trying to get peoples opinions on this so i could get an idea of how to do it

I think they misunderstand the year... the plastic thing was the pump module, which was on my 92. The 89 should not have it, it should have a pump mounted to the metal base and a hose to the pipe above it. You could splice a pipe to the pipe the pump goes to, then weld it to the pump mount to stabilize it. I wouldn't run a hose the full length, but keep it minimal. The 83-4 diesels had just a hose at the bottom, no special sump like the 85 and newer had, so it is not a problem to go that way at all. I don't see a hose collapsing unless there is blockage somewhere. My reasoning for not having much length is more about degredation than collapsing. Not sure I would want a brass fitting rubbing on the bottom of the tank either...
You do not HAVE to use IDI senders, but you COULD use them. The sump at the bottom of the factory senders tend the break off and then you run out of fuel at 1/4 tank, mine both did, so now there is anhydrous capable neoprene hose at the bottom of my senders in the 86. It is also what I used on the 92.

 

[Fellro]

yea while i was dealing with the fuel i was gonna put a pressure regulator on the fire wall somewhere in the system along with a fuel pressure gauge

Only need a regulator if you use electric pumps. The transfer pumps in these trucks are about 6 psi, their only job was to supply fuel to the high pressure pump that is on the frame.

Question: are you planning on running dual tanks?

 

[crzybil87]

yes both my tanks in my truck now are relatively new replaced about a year and a half ago so i wanted to use both of them

 

[Fellro]

If you do not use the transfer pumps, you will have to use a pollack valve. The factory Ford part is tough and expensive to find, but an aftermarket 6 port would work as well. You would use the pump wiring to change the valve position. The trick is in getting the switch working, because the pollack switches use a change in polarity to change the direction of the switch. I set up a pair of relays to do the polarity change. I would have to sit down and do up a wiring diagram again, since I know that one is long gone..

 

[crzybil87]

by transfer pump you mean the pumps on the sending units, sorry im a visual learner, but if i dint use them i would need the relays and pollock valve you were talking about

 

[Fellro]

Yes, the transfer pumps are the ones on the sender, they simply transfer fuel from the tank to another pump, whether the high pressure gasoline pump, or a high pressure injection pump.

The 92 Cummins mechanical pump has a priming lever on the side of it. The only advantage of using the electric pumps on this occasion would be the easier installation due to the dual tank issue.
6 port Pollack valve
http://www.autozone.com/autozone/ca...ditional-prod-images/en/US/wl2/FSV2/2/image/]

 

[89PSD]

using a gas intake pump on a diesel truck is a no no. that pump will wear out and stop pumping fuel and your burn out the fuel pump on the motor. If you wanted to pump diesel for any length of time you need a brushless pump.Fuel Lab makes a few, areomotive does not.
or use a 99-03 7.3L fuel pump. They use a electric fuel pump mounted on the frame. There about $50-100 at wreckers or new for about $300. But make sure to get a reguloator they build 70+psi and thats far too much for a cummins

what pump are you going to use on the engine? the factory VE pump (being its a 92) or you going to convert it to a P-pump???

I would use the diesel pickup tube, 1/2" fuel lines

 

[crzybil87]

the mechanical pump or "lift pump" , i was gonna remove and go to an electic pump in place of it, so i have to figure out a way to use both tanks and and tie it into that electric pump

 

[89PSD]

Or you could get a airdog system... it filters air from the fuel, water and gunk has a built in regulator and pump... pirfect for taking the fuel from the tank, filtering and pumping it to the engine.

 

[Fellro]

You could set up a pump on the frame, power it by the wires to the high pressure pump that is there now, place it by the pollack valve, and have it controlled by the wires that currently run the transfer pumps. You want the electric pump as close to the tanks as possible. It depends how much you want out of this thing as to whether it would be necessary to go to 1/2 lines. 450 HP isn't really all that much... it has 3/8 lines now. To change it to 1/2 would require full replacement on all the lines, as the factory sender unit is 3/8.

If you were to go for the PS pump, you would need a feedback regulator, as the injection pump only needs 5-7 psi supply...

 

[89PSD]

you would put the airdog after the tank selector valve.