Well guys, I have had a friend come to me with a problem that is way beyond anything I have encountered. Search has not afforded any answers and the TM's have not even addressed the problem (symptoms).
He has an M39, something...he has just installed a remanufactured (AMBLAC?) injection pump and is trying to get engine to run. The engine ran like a top several months ago when he first started this project and felt the need to replace the pump among other items he is doing. (The truck is far from running at this time...) He is frustrated and ask for assistance.
My experience has been to bleed all the fuel points, spin the over to assure lubrication and give a short shot of starting fluid to get the injectors to bleed and up they start. NOT this old girl. We have spun her over so much that we are using Little Truck to slave the LDS. We can checked the timing several time and it is good. Fuel has been bled from all points. A good shot of starting fluid will get her to run and she is smooth as silk at 1400 to 1500, not wanting to go over that considering that he does not have any cooling system.
ISSUE, if the RPMs drop below 1100 they continue to slowly settle to 0. (Slowly being 5 seconds or so.) I have never encountered anything like this.
He does not have computer access so I am acting as and in-between. I will scream if Squirt acts like this when my remanufactured pump goes back on......
So this is a complete IP, not a HH swap? Just making sure the head isn't 180* out from the pump itself. Is this a reman pump? What is the date? Maybe it needs to "break in". I have yet to install a complete IP. I know the reman HH start right up, maybe the complete IP needs to be run for a bit? How long of run time has it had? Is there a start up procedure for a complete rebuilt motor?
Gimp, good questions. I have installed re-mans before and while being slow to bleed, generally start-up in a few minutes of crank time.
This was a complete re-man, has been on the shelf for a few weeks. It was supposedly bench run on an American Bosch set-up machine. No start-up procedure given by the company that did the work.
Have you ever gotten a head in 180 out? What does the engine do? I have confirmed that the timing pointers are correct and the grooved tooth (normally painted red) is one tooth past the other pointer.
There is not more than one grooved tooth is there????????? How can I confirm if the pump is timed properly, internally. (Short of opening my spare pump and putting it on his engine.)
I am game to re-time the pump with the crank 360 from where it is (180 on the HH) but I cannot afford to kill his engine, that is why I ask what happens if one is 180 out.
I had this happen on two differant trucks of mine. One, the fuel cut off looked like it was all the way forward but was at about 6 oclock. Removed the shut off lever ,lubed and re-installed nice and loose no problems.
The other would run as you have described, lots of cranking, jam a gassed rag in the intake and would fire, then run wild almost to governor then slowly calm down and struggle to run goosing the throttle to keep 1K rpm. I replaced the head and it purrs like a (whisteling) kitten.
I don't know if it would run at all or very well if it were 180 out. If you pull the front valve cover and check that both intake and exhaust valves are closed when all your marks are aligned you should be good.
I also forgot to add that when I removed the head there was a small amount of diluded motor oil/diesel in the shut off area, so i assume the head was worn and leaking fuel by the plunger. There is also a guy in the classifieds that has a guarenteed good new/ or rebuilt pump for sale.
The fuel cut-off lever may be sluggish. When held in your hand the lever portion must turn under its own weight.
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Bjorn
MEP-018A (needs new generator head)
Avatar: XM757 in OK prepared for 1,000 mile trip home. Part of 6,000 mile journey in 2006.
1968 M49A2C modified with 1960 M756A2 truck bed and 1975 HIAB 765A knuckleboom, exhaust brake and more. (SOLD)
1969 Ford XM757 8x8, 5-ton Pershing 1A truck tractor...the "improved MV".
"Some things can't be made better, just differently......a lot of things actually"
I have managed to install a replacement HH 180 out. The engine is very hard to start, will not run smoothly at low rpms, and will lose power until it stalls. It has virtually no pulling power. Mine would move the truck around (M35a2) but could not go up a slight grade in low/1st. But it would run. Once warn it would idle with the hand throttle set to 1000rpm or so. Kinda sounds like yours.
I have managed to install a replacement HH 180 out. The engine is very hard to start, will not run smoothly at low rpms, and will lose power until it stalls. It has virtually no pulling power. Mine would move the truck around (M35a2) but could not go up a slight grade in low/1st. But it would run. Once warn it would idle with the hand throttle set to 1000rpm or so. Kinda sounds like yours.
Mark, this post is why I asked. If the HH is 180* out, you would line everything up according to the marks, pull the HH out, turn the motor one revolution and re-seat the HH.
I figured a rebuild would not have this issue, but we have seen many things with these trucks(MVs) not right. It is a PITA so I would rule out all other options first.
No idle, but runs at 1400+??
