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I would spin the engine over by hand and check the piston height. Bent rods from too much power, liquids in the chambers like: coolant, water, or oil. CDR ProVent maybe a source of oil? (Restricted and sucked oil from the drain or overflowed. Massive blowby overwhelmed it? Just thinking out loud here.)
The "clean" valve is a concern - why is it spotless? Valve guide dumping oil maybe?
The amount of "dirt" in the combustion chamber is a concern: is the engine burning oil? Turbo shaft seal? Hole in the intake letting dirt in? I don't see this kind of build up in the engines I have torn down, but, I ran them hard. ( I did see it in the 1992 with extreme miles and oil burning from the CDR blowby / bad rings issue...)
Did the valves hit the pistons and get bent? I would inspect the timing chain - it's due at 60K anyway and Leroy has a gear kit to eliminate that problem chain now...
Maybe a lifter came apart and ate the camshaft - some sort of INOP valves or intake restriction?
Possible carbon, from the pictured mess of a buildup breaking loose, is sticking some valves open?
Ring failure or defect causing them to loose tension?
As the heads are being checked one has to check the block for warping. I didn't see any signs of a blown head gasket, but, I am not there and it's hard to see.
They should go 500,000 or moreWe would love to know what caused the loss of compression before you 'dump' it. You have a lot of fans out there of the guide and of this build. The engine under DD use shouldn't have failed. Do consider that 60,000 miles is a lot of miles so you did get some value out of the 3rd engine. Sure they should go 100K or more, but, things happen. Hopefully the engine can be patched cheaply and dropped back in.
Thanks, I'll check that out. I was thinking of going back to bolts anyway.I see a few issues with your head gaskets. There appears to be a few places where you're not getting good seating. What's holding it up? I see one thing so far. The block dowels appear to be damaged. This may have been at rebuild or trying to install heads over the studs.
I'm uploading one that I caught that is causing you grief.
Also, I'd ditch the head studs, these things cause nothing but grief in sealing and compromising the head gasket seal by it getting wet at the threads. They also cause alignment issues when trying to install a head gasket over them and then then head.
I'd clean these heads up and deck surface, replace the dowels, and install with new head gaskets and new heads bolts.
Been there
Also, I'd ditch the head studs, these things cause nothing but grief in sealing and compromising the head gasket seal by it getting wet at the threads. They also cause alignment issues when trying to install a head gasket over them and then then head.
Bolts are proven to stretch, break, or loose clamping force and pop the HG's generally average around 200K. Some more some less.
The block was bored and check when at the machine shop. I told them to do what it needed, they said the deck & main bores were fine. Heads were new AMG .Other issues could be the block's deck surface being straight. Was this block decked? This needs to be checked.
The cylinder heads themselves could be untrue, this needs to be checked as well.
I planning on doing something like this but using the starter to check compression, not running it.Since this engine is MFI it could be rigged to start on a stand. Make the repairs to the head/gasket situation and re-assemble on the stand good enough to fire up. Run it, then pull compression and see if the repairs solved the problem.
Thank you! You just made my case! What in the world is wrong with something that lasts for 200k miles.
Nothing's perfect, the TTY bolts do fail, sure. I've seen soft ones made that wouldn't hold torque new. Stuff happens in the production word.
Just saying that a person doing head gaskets will have a much higher success using bolts than studs.
Try building an engine for a customer with studs in it and having confidence that it won't come back because of them.
I've said my peace.