That Crankcase breather is disposable maintenance item. I think every 20K Miles I think. And your right about it probably is causing your oil intrusion. Changing injectors can't hurt, but your injection pump is on it's way out, and probably gummed up also. I hope you change the glow plugs or at least check them. FYI you check compression through the Glow Pugs. If the injector tips are wet, then there leaking. your looked just black with carbon from what I saw. means there not dripping. I've seen the GP controller cause that problem, but use a code reader first to pull up the code. New fuel return lines were smart. I been around GM 6.2 and 6.5 all my life. In fact a 86 M1028A2 is my daily driver. Tom
Thanks for the comments, wish more would. Glow plug controller is brand new. All plugs have been checked and bad ones replaced. I used to have the adapter for the compression tester that screwed in the injector hole but Ive lost it. We used it to check engines without glow plugs. The ends of seven injectors were wet and left a mess on my table, I think I only showed them in the Video after I had wiped them off and cleaned them up a bit because I was putting them back in the boxes for the core charge and didn't want to return them a mess, the parts guy is a personal friend. At last the fuel pump. I have a deep suspicion the seal is bad in the fuel pump causing the oil intrusion, the pump has already been changed but I think the previous owner might have starved it of fuel. I just started with the injectors because it might solve 2 problems and they are relatively cheap. Probably would have changed them out anyway because I want to give the museum a dependable truck, and with it having the 6.5 it kinda ties in with the legacy of the 6.2 and 6.5 of the old CUCV and Humvee. Right now though it's electrical gremlins. When I brought the truck home several things were not working, started searching, wasn't getting proper voltage on signal wires etc. Plugged 2 scanners into the port, no reading from the ECM. Bought a new one, plugged it in, everything worked, found the fuel delivery problems. Disconnected the batteries, changed the injectors, hooked everything back up, now nothing works again and the check engine light flashes and fades and no start and the scanner will not detect the ECM. So now it's down at Bobs, in a proper shop. He can track down if it really is the ECM and if so what's popping them, at 200 dollars a pop, the one that's in there now is only a month old. Long winded I know, I am just stating all this so others in the future might be able to get some help with this, when we discover the problem, it and the cure will be on a future video. Thanks again for commenting and encourage others to do so!!!!! MUCH APPRECIATED!!!
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That Crankcase breather is disposable maintenance item. I think every 20K Miles I think. And your right about it probably is causing your oil intrusion. Changing injectors can't hurt, but your injection pump is on it's way out, and probably gummed up also.
I hope you change the glow plugs or at least check them.
FYI you check compression through the Glow Pugs.
If the injector tips are wet, then there leaking. your looked just black with carbon from what I saw. means there not dripping.
I've seen the GP controller cause that problem, but use a code reader first to pull up the code.
New fuel return lines were smart. I been around GM 6.2 and 6.5 all my life. In fact a 86 M1028A2 is my daily driver.
Tom
Thanks for the comments, wish more would.
Glow plug controller is brand new. All plugs have been checked and bad ones replaced.
I used to have the adapter for the compression tester that screwed in the injector hole but Ive lost it. We used it to check engines without glow plugs.
The ends of seven injectors were wet and left a mess on my table, I think I only showed them in the Video after I had wiped them off and cleaned them up a bit because I was putting them back in the boxes for the core charge and didn't want to return them a mess, the parts guy is a personal friend.
At last the fuel pump. I have a deep suspicion the seal is bad in the fuel pump causing the oil intrusion, the pump has already been changed but I think the previous owner might have starved it of fuel. I just started with the injectors because it might solve 2 problems and they are relatively cheap. Probably would have changed them out anyway because I want to give the museum a dependable truck, and with it having the 6.5 it kinda ties in with the legacy of the 6.2 and 6.5 of the old CUCV and Humvee.
Right now though it's electrical gremlins. When I brought the truck home several things were not working, started searching, wasn't getting proper voltage on signal wires etc. Plugged 2 scanners into the port, no reading from the ECM. Bought a new one, plugged it in, everything worked, found the fuel delivery problems. Disconnected the batteries, changed the injectors, hooked everything back up, now nothing works again and the check engine light flashes and fades and no start and the scanner will not detect the ECM. So now it's down at Bobs, in a proper shop. He can track down if it really is the ECM and if so what's popping them, at 200 dollars a pop, the one that's in there now is only a month old.
Long winded I know, I am just stating all this so others in the future might be able to get some help with this, when we discover the problem, it and the cure will be on a future video. Thanks again for commenting and encourage others to do so!!!!! MUCH APPRECIATED!!!