Anyone Know anything about Fuel Pumps?

[Oh2Ranger]

I have a 1994 Ranger that I'm planning on doing a Diesel Swap into. I haven't really got all that far into it yet, so I haven't started a thread or log, mostly just planning and trying to figure out a few thoughts first. I already have the truck to swap the motor into, and I already have the Diesel, so I'm set there.

I'm trying to understand how the fuel system works / how I'm going to make it work with the transplanted engine. Gasoline engines require higher fuel pressures, and because of that, I cannot use the stock fuel pump to bring my fuel to the injection pump. I really only need 2-3 PSI in the lines before it hits the pump. I would like to retain the fuel level unit so I have a functioning gas gauge once I'm finished, but it looks like the float / pump are one in the same unit. I'd think that I could disable the pump by pulling the relay and attaching a hose that would bypass the pump in the tank, add a lift pump on the frame and be set? I thought I'd just run it by the experts first.

I'm assuming there are 3 lines off the cap on the tank too? Vent, Flow, and return?

I'll probably post something in the diesel swap forums too, but thought I'd see what the ranger guys think.
Thanks!

 

[adsm08]

The pump can be removed from the sender, so your idea there is valid.

If you think she could handle 5-10 PSI, the 86 to 88 trucks had a low-pressure in tank pump that will fit your sender.

 

[Oh2Ranger]

I don't know If I'd feel very good with that pressure going to the injection pump, I will have to look again, but I think that it wants about 3psi to the injection pump. Its being rebuilt now, and I don't want to have it start leaking / blowing any seals. Others have recommended regulators, but I feel like that is such a dramatic step down in pressure and you would be so heavily reliant on that piece of equipment to work.

What should I expect to see when I take a look at the tank? Looking down the frame rail, I would expect the 3 hoses that run in unison to be a venting hose, return hose, and a fuel pull hose.. Is there anything more? Is that pump going to come out gently or is it going to be a hack job? (made to be able to be removed?)

Id expect that I could just bypass the in-tank pump, add my inline low pressure pump on the frame rail, and be set.. being able to retain the return line and vent?

 

[adsm08]

Yeah, the pump is made to be removed from the sender. Airtex makes a pump-only repair kit for it.

The 3 lines you see are feed, return, and vapor. The vapor line will only be truly needed to keep the tank sealed up since diesel fuel doesn't usually have the evaporation issues found with gasoline.

The actual removal of the pump will require a hammer, but it should come out easily. Just knock the locking ring off.

 

[goodie85]

I don't know If I'd feel very good with that pressure going to the injection pump, I will have to look again, but I think that it wants about 3psi to the injection pump. Its being rebuilt now, and I don't want to have it start leaking / blowing any seals. Others have recommended regulators, but I feel like that is such a dramatic step down in pressure and you would be so heavily reliant on that piece of equipment to work.

What should I expect to see when I take a look at the tank? Looking down the frame rail, I would expect the 3 hoses that run in unison to be a venting hose, return hose, and a fuel pull hose.. Is there anything more? Is that pump going to come out gently or is it going to be a hack job? (made to be able to be removed?)

Id expect that I could just bypass the in-tank pump, add my inline low pressure pump on the frame rail, and be set.. being able to retain the return line and vent?

4bt diesel I'm assuming? if thats the case I would put a regulator right up by the motor with a gauge and set it how you want it. Thats what I've done numerous times with the 24 valve cummins. Have the pump in the tank if i recall right you should be at around 5 psi for pressure on a 4bt not quite sure? Then the pump from the tank to a helper pump(if needed) then to a regulator then to the lift pump.

 

[the_intimidator03]

I just replaced the sending unit on my 88 ranger and there is a little clip that holds the in-tank pump in its place. it connects to the pick up tube via rubber hose. you can remove that and replace it with another length of tubing and filter so that the pump itself is not a hindrance to fuel flow. Also if need be I can take some pictures of the set up (slightly mangled from pump removal)

 

[Oh2Ranger]

Thanks guys, It looks like I'll dig in there and see what it looks like, and check back if I have any other questions.

Thanks Again