Coolant In Cylinders Question

[BC77]

Hello all looking for some help. I have a 2010 peterbilt 387 with a Cummins isx cm871 that has been De Mandated. I had a inframe done at 1 million miles. 115K miles since the i frame, I went to pick up a load, shut the truck down and when I went to start it about 5 hours later it wouldn't start. It was acting like it was a starter issue. Come to find out it was hydro locked. So I get it back to my place, drain the oil and about 2 gallons of coolant is in the bottom of the oil pan. I messed up and didn't do a pressure test before taking the radiator off either. I get the head off and coolant is in all 6 cylinders with #4 having the most. I took the head to get it tested and it checked out good, head gasket looks good too. I had a coolant line bust about 10 days prior and pulled over as soon as I noticed, I don't think it over heated but not 100% sure. Any ideas about coolant in all 6 cylinders??? On the inflame New head, liners, pistons, rings. When I removed the injector cam is was knicked up in several places also, valve cam still looks good. I usually cruise control around 68 to 70 mph

[tree98]

You really should have done a thorough pressure test on the cooling system with the oil pan off looking up into the cylinder's for leaks. Now it's anyone's guess what your dealing with. The fact that someone tested the head and decided it was good doesn't mean much at all. You said the head was replaced during the recent rebuild. Is it a brand new OEM head from cummins or something Chinese from ebay or somewhere??

I guarantee it wasn't rebuilt properly though. Sounds like it needs to be done correctly this time by cutting the couterbores, using ONLY OEM parts, and letting the head sit overnight for the gasket to crush before the final torque, etc.

[Rawze]

yeah.. someone f#ucked up real bad by taking it apart like that without even troubleshooting what happened first.

Locked up engine ...
** removing the drive belts and trying to turn the engne by hand to see if it frees up.. or is actually stuck. Sometimes a locked-up engine is the alternator or other component. Can also be a tranny issue.

Suspicion of Hydra-locked =

** ensuring there is no coolant getting into the intake ... pressurizing coolant system and checking turbo, egr cooler, air compressor, etc.

** after that ... pulling a vacuum on the coolant system to prevent possible further intrusion, then removing the injectors to find out what cylinder(s) is/are full of coolant.

=======================

The oopsie is already done at this point, so the next questions are...

* What s the current liner height?. - if it is less than 0.015".. then counter-bore it and set it to 0.015".


-== Assume the head is bad (even if it is not), and replace it with a brand new one OEM-only, ... otherwise, a repeat of history has a very high chance.

-== Replacing the connecting rod for the cylinder that it hydra-locked on, so that the engine does not end up out of balance due to a very slightly, hard to tell, bent rod.

-== and then inframing the engine this time around, as specified in this post.. and nothing less...
http://rawze.com/forums/showthread.php?t...6#pid70606
and...
http://rawze.com/forums/showthread.php?t...0#pid67840

[Rawze]

(05-15-2023 )BC77 Wrote:  Hello all looking for some help. I have a 2010 peterbilt 387 with a Cummins isx cm871 that has been De Mandated.
...

The next and most obvious thing is to ensure the de-mandate programming is good. Assume it is bad until you get it properly reviewed.. as 90%+ or all de-mandate programs will absolutely shorten the engine life,.. and that is the last thing someone wants. -= Never, EVER take this for granted!. It is a $40,000 commercial engine that people have to make their living with ... and not some da$mn half-arssed redneck pick-up truck engine that can be thrown away if someone screws it up!.

Copy that program out of that ecm and e-mail it to me so that it can be properly reviewed of what someone did in there.