Liner O-ring failure

[Rawze]

First and foremost, that o-ring will not normally leak unless the liner started dancing in the block. The brass shims will always hold back the coolant unless someone installed the liner with debris on its brass shim, or the liner was dancing in the block. The o-ring is simply a back-up to this.

I.E.> The liner o-ring is a 'back-up' o-ring, and not the primary means that keeps the coolant held back in that area of the engine.

The pictures show that o-ring is deteriorated heavily due to rot alone (oil or some other contaminant in coolant at one point) so badly, that if it were the only thing holding coolant back, it would have failed a long ago. The fact it started letting coolant past it at this point, is the liner moving around .. not the o-ring itself.

The mid-stop in the photo shows that it is also heavily fretted on the thrust side, pointing to this as well.

So all things in the photos so far heavily points towards a liner starting to dance.

Any signs of a head gasket failure too?

How about micro-etching in the bottom side of the head where that liner sat? head is likely fretted too. - This would give it away, even if there were no other visible signs.
an example on how to spot this: http://rawze.com/forums/showthread.php?t...48#pid7648

Also,.. is this the same engine that had the unknown quality ecm program that you sent me back in march to review???.

That file was good ... it had gotten straightened out by the time you purchased the truck ... but what about prior to this?. What about the last owner, and its older history? ...

I just so happen to have the bad delete that used to be in that truck a long time ago. It was back in oct-2021.. before you purchased that truck.

- Here is what was in that bad delete program that eventually got straightened out, here it is at a quick glance...

** The injection timing was ridiculously too high and extremely harmful to the engine. Could cause liner dancing and/or overheating of the cylinders. Can also cause a cracked piston

** turbo was programmed to absolutely destroy that engine with more than 38+ lbs of boost. A CM2350 without EGR can only handle about 33,34 lbs boost before it becomes VERY harmful. - Combine this with the fact that it was set at 2050trq/600HP.. and this alone would have made something eventually come apart in it... + destroy turbochargers due to over-spooling.

** Amonia clamping and other aux. emissions systems were not switched off properly, so this would have screwed with it in negative ways too.

** The fuel pressure tables were jacked way up, making it really hard on the pump + making the cylinders too volatile. This is harmful as well.


-== There are also other issues in the program. Those were just the highlights that might have contributed towards the most likely progressive damage that it suffered in its past. this all before you purchased it. it did have 580,000 miles on the odo when the program was finally straightened out correctly the first time, and who knows how long it ran with that bad delete in it.


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This truck is also a decent example of why I always try to warn people about buying into a half million miles old truck with a square nose, combined with big HP, and geared wrong for hauling any freight ... it have been lugged to death its whole life below 1500rpm's, can hardly get out of its own way bobtail, nonetheless can climb a decent hill fully loaded with those garbage tall rear ends.

It being a 600/2050 set engine in a truck with tall 3.36 rears + driven hard (the bad delete file also gives that away too thru the low fuel mileage it had at that time) ... .. I would say it lived a longer than expected enough life if it made it past 750k.

(just for education for other people reading this )...
-= Thus is what a person gets when they buy into a used square-nose truck with 500+k miles + power set to 600HP/2050 .. It tortured and lugged to death because it is geared too tall, and all the rest of the abuse that it had likely suffered to begin with.

.. so 750k on the odo before it gave up the goat? .. i would say that in this case, you got lucky. It should have failed (predicatively) before it got to 650k... yet you got an extra 100k miles use out of it above this.

The question now is ... Did you know already that it was on borrowed time, and was this notion a part of your business plan?. - Because it should have been from the day of purchase.

Can it be made to NOT do this again?... sure, with building it to the specs talked about on the forum here.. 100% to the letter, no shortcuts
ref: http://rawze.com/forums/showthread.php?t...6#pid70606

.. + get rid of those garbage rear ends and put a decent set of 3.90's in it (maybe even 4.11's, as it is a square nose and should not be driven more than 70+ mph .. ever ... any ways) like it belongs. Set the the power to 575/1820trq. This is plenty for a truck with a set of decent 3.90's in it to climb about any hill while lasting that next million+ miles.