Torry Stewart

I have 1990 Dodge diesel truck. It's been a great truck, until now. Every time I drive it it dies about a 1/2 mile from the shop. I have put another Injector pump, 2 lift pumps, new injectors, new voltage regulator, alternator checked (good). It seems like something is killing voltage to the FSS. When it dies we have to bleed the injectors to start it. When the truck was running good, I did have replace the steering column(with wires) with an used one. This may be the culprit. We are tired of guessing. Any help is appreciated.

maybe368

Sounds like you have a suction side air leak, they can be hard to find because there is generally no fuel leaking. You can try pressurizing the fuel tank with a few psi and look for fuel leaks...Mark

Torry Stewart

Yes, Mr. Mark I tried that also. I am willing to try it again though. I had my friend keep applying pressure and I had soap bubbles. I sprayed all the fittings. Is there a better way? Thanks.

maybe368

What I did was put a compressed air line into the filler neck and stuff some rags around it to seal it a bit. I applied too much pressure when I did this but just a few psi will do. Get 5-10 psi going into the fill tube and wait a few minutes for fuel leaks to show...Mark

Torry Stewart

Thanks I will try it again.

torquefan

If you suspect voltage to the FSS, you can try running a temporary jumper from the battery to the FSS and go for a drive.

Is the problem predictable enough that it will quit every time after so many miles?

Torry Stewart

I have tried that also. I wired 12 volts to the FSS and the truck still died. We have been have chasing this problem for a while now. I have a red light in the cab that I have wired in parallel with the FSS. I will put it in series with the FSS and try again. Every time we make a change we can drive it 5 laps around the shop then it dies. But when it dies we have to bleed the injectors to get it to start. So whatever is killing it is stopping it from getting fuel. Thanks for the help.

mknittle

I once had something like this happen. turned out to be a rubber hose that looked fine on the outside but the inside had a spot that would collapse when it got any pressure. I suppose suction could do the same.

oliver foster

Sounds like it is sucking air to me.

oliver foster

You could try a jerry can of diesel and a new line to the LP and see if it fits the problem.
That would at least isolate the problem area from the LP to the tank.

patdaly

If you have to bleed the Injectors to get it fired, it is not electrical.

As has been noted, find the air leak, better yet, just do a preemptive strike and replace all the rubber hoses from the tank to the engine, supply and return, they are old and tired.

Torry Stewart

Thanks I will go back to the fuel system.

Torry Stewart

Thanks for the advice I have been getting. I looked over my fuel lines. I did notice that the rubber fuel line that goes from the metal line to the lift pump was very flat. I took it off and out a clear hose there. We fired up the truck and notice air bubbles coming through the line. During idle we could see bubbles coming through the line. We pushed on the gas and the bubbles would increase. Is that normal or should you have a full column of fuel?

Torry Stewart

Clear fuel line from metal line to lift pump<br/>

maybe368

There should be no air in the line, I think that you found your problem. Now you just need to find where it is getting in...Mark