12 V swap - Bad lift pump/primer??
 

So my donor '95 Dodge ran fine for the 2-3 wks I drove it before I removed the motor. It's basically installed in my '78 Ford Crewcab.

I did nothing to the fuel system except remove the rubber lines where they attach to the supply & return lines up near the head.

The motor started on the first try the other day. I then ran out of fuel:argh: , reprimed it by bleeding at the injectors and using the primer button. Took it for a couple short drives and it acted like it was running out of fuel. So I replace the supply line with hard lines and short sections of pushlock fuel line & fittings.

Now I can't get it to start:argh:. I think the primer is faulty. I even took off the hose that connects between the heater and the pump and installed a long length of hose from the pump to a canister of diesel. The primer bulb has basically ZERO resistance and I can tell it's bringing some fuel up cause if I take the line out of the can I see just a little draining back.

Now the primer is leaking:dang:. I heard there's an o-ring in there? Sounds like I should replace it?

If the primer is working properly you should have resistance when you push it. How many times are you pumping it?

See that's what I thought. When I originally removed the motor I had it sitting on the floor. I pushed the primer a few times (didn't know any better) and you could tell it was pushing fuel, then on the last push it went in really easy. I bet I pulled in air on that last stroke. Now it feels like that all time, no resistance.

At least 40 ish times. When I was having issues with starting the last few days I'd push the primer 30-40 times and I'd start to hear a faint "hissing" and fuel returning to the tank. After that it would start after a couple of attempts.

But now I can't even pull fuel out of a can and I have fuel leaking from the primer.

Yeah it's definitely an issue with the primer. I'm not sure if it's supposed to but I'm pretty sure the fuel shouldn't be flowing back either. Could that be a sign of a bad overflow valve? I'm pretty sure that's one of the symptoms of it being bad, which would add to the no start issue you're having.

I had a similar issue with my Kubota this last week. Over the course of the 8 months it sat I played with the primer at some point and had the same issue it sounds like you. I really thought it was the primer so I took it off and cleaned it up and inspected it... it seemed fine.

I ended up gravity feeding off a small tank directly to the IP and had it running. I then did the same thing through the lift pump... and double checked the primer was working. I also installed an electric pump about 2ft off the tank and primed the entire system with that last. Then checked the primer and it had pressure. Works great now.

I dont use the electric pump, it is a pass through and is there just in case I ever need it again. Heres the pump I used in case you want to try it. (its got 5/16 barbs not 3/8 like it says)