When an I/P fails, does it just not work at all, or does it exhibit certain things that will tell you it's starting to die?

When you get a new I/P, does it come pre-set as far as fuel and timing?

 

Pumps should come set per application.

When they fail they can do many things from not pumping at all to causes an intermittent miss. Depends on what part of the pump failed.

 

There are a wide range of possible symptoms, not all of which are obvious. Low MPG, stalling, stalling on decelleration (I had that one), smoke, failure to start hot, and he list goes on.

What is yours doing?

The timing is more or less set so if you line up the marks on the IP and drive gear housing, you can get satisfactory timing. In a perfect world, you would find a diesel tech that knows how to time these older diesels and have him time it with the pump installed in the truck. The catch is not many still know how to time these older diesels.

 

It started the hard starting thing......thought it was glow plugs, not so. Checked for air leaks, put the return line kit on to be safe, no leaks anywhere, at least as i have checked every fitting/line/connection many times....nothing. Lift pump was checked, 4psi output. The fuel filter is full of fuel after sitting for long periods of time.

The starting goes like this: Wait to start light on for approx 10-12 seconds, normal, crank engine 15 - 20 seconds no start acts like it wants to. 2-3 min later same routine but it fires for 4-5 sec then stops, wait again, same routine but fires this time. Real rough idle for 10-15 sec after it fires and clears up after revved to 1500-2000 rpm. If the engine is hot, it's 10 X's harder/worse to start. Mileage has gone down, not sure how much, but once it's running it seems to have the same power, maybe a little more smoke.

This is my first diesel....when it runs right I love it, but this hard start is getting old. Last winter in 10-20 degree weather, it would fire within 5 seconds of cranking cold, never a problem. This started about a month ago. It stays in the 60's here overnite now.

BTW, its a '94 w/162k. It had a Ford reman engine put in 30k ago (previous owner and reciepts), he thinks they used all the original bolt on parts ( I/P/starter/alt/ect) but wasn't sure.

How about injectors? Is there a test I can do? just replace them?

Thanks for your help guys....I sure appreciate it!

Dan

 

Wait for some other opinions before making a desicion, but it sure sounds like an injector pump.

Injectors can cause a misfire, but stalling like you describe is not very likely because several would have to fail in a short amount of time, and thats not very likely to happen. If you can find a good diesel shop, he can pop test them for you.

What might be worth a try is to put a liter of dex3 ATF in the tank to see if that loosens anything up.

 

That still sounds like an air problem to me.

How much flow is the lift pump producing?

1/3 pint in 10 seconds is what it should be.

 

Sounds like air to me as well. The injectors can be leaking internally at the pin and seat, or between the housing and the head. I would remove the unit that is currently leaking and check to see if it is leaking at the housing, and let that determine if you pull the rest. The stream of fuel at the injector sounds like a small pin-hole rather than a typical leak. The o-ring kit does not include the supply/ return seal kit, you should purchase those as well.

 

As far as the return lines, all hoses, clamps, o-rings and caps have been replaced. I have all of the injectors out to replace the washer that came with kit. If there was a hose with clamps anywhere in the system, it has been replaced. What is the supply/return seal kit? Thanks for all the input guys, I don't want to just start throwing parts (& $$$$) at it, I want to find the actual cause so I actually learn about this truck.

Dan

 

I was thinking 6.9- The supply/ return seal kit is a pack of 3 rubber seals that fit over the supply X2 and return X1 line, and prevent the leaking of fuel and air at the 3 points. When I did an injector pump seal kit, I noticed the seals at these lines were severely deteriorated.

 

When you removed the injectors, did you notice some or all of the injector tips were wet with fuel?

Wet tips are a good indication the injector is not sealing when it pops closed.

 

It totally sounds like air intrusion to me as I've been fighting this since I've had mine, '94 also.
Go down about five-ten posts below this one and look for the "can I remove one of my return lines" post. I think this is what MY problem is now that I've eliminated everything else.

O>>R>>

I'm still learning this truck's injection/fuel supply system but it seems to me if your fuel filter actually is full (are you sure?) you must have an IP or injector problem since it definitely sounds like you have air in your system by the way it runs.
I thought a lot of times my filter was full but after I put on a cheapo elec. fuel pump to purge the system I could pull the Scraeder valve out and run air out of the filer. So my assumption was false.
BTW the best thing I did was to install the cheap fuel pump on my truck, it has helped me solve a lot of my fuel supply/air intrusion problems. I only run it to purge air with the schraeder valve out so hopefully it won't F.U.B.A.R. my fact. lift pump.

 

This sounds like a worn out IP.......... hard starts once warm..... Stalls at stops can be a dirty internal/worn IP.

Do you put your foot to the floor or at least 1/2 way for all starts "cold".

If you have replaced the return line kit then disturbed it after a month or so you may have an air leak still. Anytime the orings and caps are disturbed there is the possibility of an air leak....... air will leak in where fuel with not leak out. If the fuel level in the IP is low due to air intrusion then start and stall symptoms would appear. It is solved when the IP is filled up during repeated start attemps.........

 

To check for air leaks, you can install a clear plastic line between the top of the injector pump and the return line and see if there are any bubbles that are getting pumped through.

Air leaks at the injector O rings will not affect perfromance once the truck is up and running. More likely if the leak is bad enough that it will merely leak fuel out as the engine runs.

 

Thanks guys I really am greatful for the help. With the holiday weekend I don't have a ton of time right now to mess with it.

As far as the cold start procedure....It normally needs about 1/2 pedal in the summer to fire. Since these problems, it doesn't really matter how much pedal I give it cold. Once its running it does not stall, idles smooth and seems to have the same power as usual. I'll put the clear hose on as soon as I can.

 

OK.....it appears my problem lies in the fitting at the rear of the driver's side on the return line. the nipples on the hardline is 3/16.....the new return line hose kit is bigger, so....I think I will fab up a complete hard line return w/fittings that match the size of the caps. I jerry rigged it up for the time being and it starts like a dream.....hot or cold. Thanks again guys for heading me in the right direction....thank God it wasn't the I/P.

BTW Dave, all the injectors were dry when I removed them w/a slight amount of carbon (?) around the tips. Talked to a guy at local diesel shop and he just suggested putting them back in and running them. The closest place that would have tested them that I could find is an hour plus away.