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Discussion Starter #1 (Edited)
Its Running again --- Engine not starting after IP servicing

Well time ask the experts, or at least someone who has more experience than I with these engines…(sorry for the length, just want to describe the whole issue)

Ok, so 2 months ago my engine died on me while driving to work, right in the middle of the road. Its ran fine for almost a year, no prior issues, easy to start. My injection pump has had a small leak from the KSB for some time. Upon the engine dying on me, the IP sprang a new leak, only instead of a drip it was a stream. When using the lift pump to prime the system, it would leak profusely, and when turning over the engine, it would be a constant stream. So I figured that it was the IP that had failed and caused the engine to die.

I sent the pump off to get serviced and to be upgraded with a 3200 rpm gov. spring. With this upgrade I changed the valve springs to the 60 lbs springs, to which I had removed the head, replaced the head bolts with new ones, replaced the head gasket and multiple other gaskets and seals to go along with this time of engine tear down. Upon receiving the refurbished pump, I installed it before knowing about how critical it is to locate the engine at TDC, since I couldn’t get the TDC pin to move before I pulled the pump, I didn’t want to risk rotating the engine for fear of the IP drive gear to jump a tooth or something. But after having played with the IP before I sent it off to the shop, it seemed to me that other than having it incorrectly timed, the notch on the drive shaft should have lined up with the key way, at most I could get it connected while the engine is in the exhaust stroke instead of the compression…

Well it didn’t start, other than for a momentary sputter. I know I have fuel to the injectors, for if I loosen the connection, fuel will spurt out from each one.

I then proceeded to remove the pump, rotated the engine to rotate the key way 360deg (figuring I had a 50/50 shot at lining it up in the correct stroke the first time) then reinstall the pump. Tried cranking and priming some more, and still nothing, but again had a momentary sputter. I repeated this a total of 4 times (I’m now really good at removing and reinstalling these pumps, 45 min to pull and replace…). Surely by now, just out of dumb luck I should have had the IP lined up with the engine, granted maybe the timing could have been off a few degrees…well on the last pump install, after cranking and cranking then finally holding the starter for about a continuous minute or two, the engine did finally start to show some life. But only while the starter was engaged, it appeared to be firing only off of the 4th cylinder, judging by the sound and by the exhaust port being warm to the touch. I attempted to start the engine for about another 30 minutes to no effect. I could see a ‘mist’ of diesel exhaust and could smell it, but the engine would not stay running.

I then talked to the service shop, they suggested that remove the pump, send it back down to them, they’ll retime the pump, and that I remove the TDC pin, locate TDC visually, and I should be good to go. Well did all that, got it to TDC via the pin, reinstalled the pump, low and behold, still nothing but a momentary sputter…

So now with my engineering acuity and mechanical knowhow, I am completely clueless as to what’s going on. I’ve scanned for related posts on here, but none that I’ve found seem to have the same issue. Yes others have had injection pump problems but then the engine was back running after servicing the IPs. I’ve been over everything multiple times; I can’t see anything that is disconnected. Any discussion or ideas would be greatly appreciated. Thanks.
 

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Just me, but I wouldn't have tried it that many times before I pulled the front cover and re-timed it the "hard way" (just like on initial assembly, at this point i have to believe it would be easier than continuing to remove and replace the pump blindly).

Of course that would only be if I was certain it was a pump timing problem.

While you are in there tab the KDP so you can be done with it.

Best of luck
 

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Are you getting a GOOD STREAM of fuel delivered to the injectors?
Is the lift pump arm positioned in the RUN position?
Is the fuel filter FULL?
If you connect a TEST LIGHT to the SHUT OFF SOLENOID; does the light stay LIT while cranking?

In general, if one cylinder is firing and then quits; it indicates a fuel supply problem to me.
 

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Discussion Starter #4
I'm pretty sure the IP drive gear has not moved, from looking at good high res pics of the gears (from magazines and other people's pictures) this gear doesn't look to have enough room to move around and jump a tooth...I was pretty careful at installing the pump (each time) to not bump the gear to knock it loose.

It's a bit tough by myself to hold the fuel line up and out of the injector and crank it over and still be able to see the flow. But with having the line loose, fuel shoots up about a foot into the air. The lift pump arm has always been a little on the limp side, it hangs about at a 45deg angle but this is how it's been since the day I got the engine. It does have good pressure/resistance when I pump it, so much so that I've gotten blisters on my fingers before back with I ran the tank out of fuel a time or two...The fuel filter should be full, I wanted to replace it but couldn't find one around. I did take it off and filled it up and put it back on and in doing so, fuel spilled over the side. I haven't checked the shut off solenoid with a light yet, I would have thought that the service place would have checked that along with checking out the whole pump to make sure that its working properly, after spending $1,100 on this pump so far, they should have checked it...

I can pull the lines again, and blow them out using an air compressor. Can I do this to the injectors as well, without damaging them? I should have just held off on replacing the valve springs and opening up the engine until I got the pump back and tired getting it to run again, though I'm sure I didn't mess anything up, it's harder now to know for sure...
 

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I'm pretty sure the IP drive gear has not moved, from looking at good high res pics of the gears (from magazines and other people's pictures) this gear doesn't look to have enough room to move around and jump a tooth...I was pretty careful at installing the pump (each time) to not bump the gear to knock it loose.

It's a bit tough by myself to hold the fuel line up and out of the injector and crank it over and still be able to see the flow. But with having the line loose, fuel shoots up about a foot into the air. The lift pump arm has always been a little on the limp side, it hangs about at a 45deg angle but this is how it's been since the day I got the engine. It does have good pressure/resistance when I pump it, so much so that I've gotten blisters on my fingers before back with I ran the tank out of fuel a time or two...The fuel filter should be full, I wanted to replace it but couldn't find one around. I did take it off and filled it up and put it back on and in doing so, fuel spilled over the side. I haven't checked the shut off solenoid with a light yet, I would have thought that the service place would have checked that along with checking out the whole pump to make sure that its working properly, after spending $1,100 on this pump so far, they should have checked it...
The service place can not test your ignition run circuit of your vehicle by having your pump at their shop. If you do not have a test light you can run a jumper lead over to the IP shut off solenoid from the battery. The lift pump arm hanging down could indicate the pump is near the end of it's life expectancy. Two things that should always be replaced before doing a transplant are the lift pump and the fuel filter. The fuel filter should ALWAYS be replaced when installing a rebuilt injection pump. Removing and refilling the filter will also indicate if the lift pump is keeping up. I never completely remove the lines from the injectors. I just look over the top of the engine and make sure I see a good squirt of fuel shooting up through the line nut. Then I tighten that line nut down and repeat the process.

I can pull the lines again, and blow them out using an air compressor. Can I do this to the injectors as well, without damaging them? I should have just held off on replacing the valve springs and opening up the engine until I got the pump back and tired getting it to run again, though I'm sure I didn't mess anything up, it's harder now to know for sure...
I see no reason for doing this if you kept the lines free of dirt.
 

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Discussion Starter #6
Just got done checking the shut off solenoid wiring, both with a light and hearing the solenoid clicking. All looks good on that end. The engine has good ground. I'll look harder to find a fuel filter, the nearest AutoZone didn't have any 3 weeks ago when I looked for it, I'll see if I can't get them to order up one.

Thanks for the input so far.
 

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If they don't have one for an 89 - 93 Dodge W/Cummins 5.9L; the secondary fuel filter for a 82 GMC W/6.2L diesel will fit. The GMC filter has a tighter filter media element.
 

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If you did not set it at TDC before removal, the shop almost certainly did upon re-assembly.
You will need to pull the front cover and align the timing marks.
 

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Discussion Starter #9
Ok, so I've got some good news and some bad news...

Good News:
Got the engine running. Went out and got some starting fluid and sprayed it into the intake, it took a while but eventually the engine stayed running and it revs up with opening the throttle. Upon restarting the engine, it fires right up within a fraction of a second, each time.

Bad News:
Well there’s a couple of things. The idle may be turned down a bit low because the engine is causing the whole truck to Bounce, where this wasn't the case before. This roughness kind of goes away with opening the throttle, but even though I don't see the roughness any more, I can feel that the engine is still rough, it's just smoothed out a little to not cause the truck to Bounce. Next, when I rev the engine, there is some noticeable lag from the engine. I drove it out of the drive way and it hardly had any get-up and go to it.

I haven't messed with the timing yet from where the pump was set by the service shop, I just bolted it right up with the TDC pin locking the engine in place. The engine seems to be running much hotter than before. Not sure on whether I should advance the timing or retard it, based on the engine lag. Guess I'll just have to try one way, see what happens, then the other way if the first didn't correct it.
 

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Discussion Starter #10
So, after messing with the timing, it still wasn’t running right, but since I only ran it for a few seconds I checked the exhaust ports temperatures. Sure enough as I suspected, the engine was only running on 3 cylinders. So I checked if it was getting fuel, and no, no fuel was coming out of the line. I checked the line then at the IP, and it was clogged with some sort of plastic and papery material. Removed the line, blew it out, reconnected it and it fired right up, running nice and smooth. The weird thing is that I know fuel was coming out of this line and all the other lines before I got the engine fired up last week on starting fluid. So not sure where this plastic stuff came from, but it seems to have come from within the IP. Weird since the IP was rebuilt and tested from the service shop...The IP doesn't appear to be leaking; I'll keep my eye on it in the next few days now that I can drive it again. Hopefully it is all fixed up and my mpg should improve. I was getting 21-22mpg before with it leaking, should be up in the higher 20's now.... :)
 
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