New IP..........New Problems

[Smokey73]

I put a new IP that I got from M&D, the Stanadyne dealers around here, on the Mule because the old one was leaking fuel at the housing. The truck seemed to run great, it's just a little slow to start sometimes when it's cold, but if you kill it when it's good and hot, then let it sit for about 20 mins, it won't start back. The solenoid will click, but no fuel goes out to the injectors untill you let it sit for another hour or so. If you just kill and start it back, it will crank right up. Any thoughts?

 

[mark7.3idi]

bad ip

 

[Smokey73]

that's what I figured, but I hate pulling that thing back off

 

[HammerDown]

that's what I figured, but I hate pulling that thing back off

Be glad you're not in my situation...I'll be on #3
My hoods be up so many times it should have a zipper on vs a hood lacth.

 

[Shadetreemechanic]

It could also be an air leak. We have been discussing the same symptoms http://www.oilburners.net/forums/showthread.php?t=29589
You can isolate the problem by getting a clear return line from injector number one back to the filter head. When it has problems starting look for air in that line. If there is no air and the line stays full when the engine is off, then it is probably the ip.
Since I am having the same problem I have been talking extensively with my pump rebuilder. He says they have a standyne test station that actually overheats the pump during testing and checks the head pressure then. He is willing to replace my pump if that ends up being it, but he says it almost never happens to a correctly rebuilt and tested pump.

 

[7.3n/anut]

are the injector seals moist or leaking? ya know those black plastic caps.

 

[Smokey73]

It could also be an air leak. We have been discussing the same symptoms http://www.oilburners.net/forums/showthread.php?t=29589
You can isolate the problem by getting a clear return line from injector number one back to the filter head. When it has problems starting look for air in that line. If there is no air and the line stays full when the engine is off, then it is probably the ip.
Since I am having the same problem I have been talking extensively with my pump rebuilder. He says they have a standyne test station that actually overheats the pump during testing and checks the head pressure then. He is willing to replace my pump if that ends up being it, but he says it almost never happens to a correctly rebuilt and tested pump.

Yeah, I called my guy the other day and he pretty much told me the same thing. He told me that if I had any doubts about his pump, he would swap it out, no questions asked. Thats the reason I went with a local builder and paid the extra$$$$$$

 

[Smokey73]

are the injector seals moist or leaking? ya know those black plastic caps.

I replaced all the seals caps and lines when I put the pump in and replaced a few injectors

 

[Smokey73]

It could also be an air leak. We have been discussing the same symptoms http://www.oilburners.net/forums/showthread.php?t=29589
You can isolate the problem by getting a clear return line from injector number one back to the filter head. When it has problems starting look for air in that line. If there is no air and the line stays full when the engine is off, then it is probably the ip.
Since I am having the same problem I have been talking extensively with my pump rebuilder. He says they have a standyne test station that actually overheats the pump during testing and checks the head pressure then. He is willing to replace my pump if that ends up being it, but he says it almost never happens to a correctly rebuilt and tested pump.

So I went ahead and bought some clear plastic line just to see what it all looks like. I hooked it all up, and drove the truck to town and back with no problems. Got back to the house and popped the hood, the clear line was full of fuel with no bubbles so i killed it and let it sit. 20mins later I came back to check it out, all the fuel had drained out of the line. I thought that this was the problem I went ahead and tried to start it up. It started with no problems at all, fired right up. It took a second, but all the bubbles cleared out of the line, but it ran fine. I killed it again and did something else for the next 20mins or so, came back and the line was still full, but it wouldn't start. How you like them apples!

 

[Shadetreemechanic]

Well, you are ahead of me. I bought the clear line, but it doesnt do much sitting in the front seat. It shouldn't have air at all. My guess/theory/shot in the dark is that when you saw no air that the air went the other way and created a bubble in the top of the ip and caused your no start. My guess is that when your truck finally started a bunch of bubbles filled that clear line after making its way through the rest of the return system.
I bought a couple of feet of clear line. Based on your experiences I think I'll put clear line from #1 to the filter, and at #2 to ip. I'll let you know if I learn anything.

 

[Smokey73]

that's gonna be my next step. I'm thinking about blocking off the line from #1 to the filter.I think i read on that on here, kinda of a quick fix if the air is getting in at the filter, if that still dosen't work the pump is coming off

 

[Diesel JD]

It sounds like you definitely have an air intrusion somewhere. I wouldn't give up on the pump, I feel like that's the issue, check all the fittings at the IP and sometimes its difficult to get that bowl on the water sep to seal completely.

 

[Smokey73]

I put clear lines between the filter head and #1, IP and #2 and a piece between the filter and the IP. Upon start up, there was no air in any of the lines. Let it run for a while and still, no air. Kill it, and the line from the pump to the IP drains down. If it's hot enough, the line from the filter to #1 will soon drain down also. Will the check ball in the filter head let the fuel drain back like that?

 

[towcat]

your pump is OK. you have air intrusion.
also, double check your pump timing. retarded timing will make your truck a bear to start.
still, eliminate the air issues first.

 

[Smokey73]

timing is set at 8.7 degrees, I'm gonna see how the fuel mileage is there before I go any further with that. I don't know where to go from here with the air intrusion, other than a new filter header and I'm still wondering about that check ball. There aren't any wet spots on any of the lines and all the return seals and lines are new.