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Discussion Starter · #44 · (Edited)
Dug a little deeper this weekend. The valve stem seals, of which I was certain was the cause of all this, looked great and seated. So the only thing I'm left with is the head gasket being the problem. I know there was silicon on the gasket and could be the cause, however there was no where the gasket was torn, allowing so much oil to the top of the piston. Considering the water coolant jacket location, it's even more difficult to believe.
I hate to say it, but maybe the rings are bad.
 

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Make sure that the oil control orifice is correctly installed and use a new O-ring.
 

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Silicone is a great sealant for low pressure applications but it can't withstand the pressures of the combustion chamber so it would likely have blown out between the combustion chamber and an oil passage, after which oil could follow the gap in the silicone back to the cylinder.
 

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Discussion Starter · #47 ·
I hadn't considered this little device. It is in there, and there is a new ring, however I didn't inspect it. I'll take a look when I get home today. I don't believe it can be installed upside-down, but maybe it's clogged?
 

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Discussion Starter · #48 ·
would likely have blown out between the combustion chamber and an oil passage, after which oil could follow the gap in the silicone back to the cylinder.
I agree, but I didn't see anywhere that was obviously blown-out. I bought new head gaskets, but may leave the valve seals inplace as they seem perfect. I guess I'll reassemble with new head gaskets, no silicone and see where I stand. Appreciate all of your input Sidecar Bob.
 

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There's nowhere that an oil passage is next to the cylinder. The water jacket is between them, all the way around the cylinder.
 

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Discussion Starter · #50 ·
There's nowhere that an oil passage is next to the cylinder. The water jacket is between them, all the way around the cylinder.
which means? oil can only be interning above or below the piston, thus rings or valve seals. Correct?
 

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The way you have the oil control orifice in this picture, IT IS IN upside down. The thin tip has 5 holes that should be inside the passage of the block, and the single hole pointing up in the head. That way, if one hole gets blocked with debris, there are others that can still pass oil to the rocker arms. Turn it around and make sure the ONE hole on the other side is clear.
 

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There's nowhere that an oil passage is next to the cylinder. The water jacket is between them, all the way around the cylinder.
True, but there are places on the top side of the gasket where oil could run across the gasket and into the cylinder without entering the water jacket.

But that is all theoretical; The only way to tell for sure would be to put a slow motion camera inside the cylinder while the engine is running and we haven't figured out how to do that yet....

If the valve seals are OK the only other ways oil can get into the combustion chamber than past the had gasket would be past rings that are in very bad condition or through a cracked head.
 

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Discussion Starter · #53 ·
The way you have the oil control orifice in this picture, IT IS IN upside down. The thin tip has 5 holes that should be inside the passage of the block, and the single hole pointing up in the head. That way, if one hole gets blocked with debris, there are others that can still pass oil to the rocker arms. Turn it around and make sure the ONE hole on the other side is clear.
SERIOUSLY?! I hope you're correct. If this is the case, maybe this is what the problem is, and nothing more. I'm usually very detailed, surprised I installed this upside-down. Anyone else weigh on on this theory/mistake?
 

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Discussion Starter · #56 ·
I believe LRCXed solved the mystery. My oil control office is in upside-down.
So, would these being installed incorrect, result in the oil, on top of the piston?
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I don't think so either Mark. It was just an observation I felt needed to be pointed out.

BUT, after enlarging and studying the 2 pictures, I Think I see your problem. Take a look at the piston where it's circled! That sure looks like a melted piston, and is that a the piston ring I'm seeing!
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And looking at the head, I see severe pitting. That is also caused by detonation. It's on the same side as the burnt piston too.
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Clean off all the oils and show us some clearer pictures of that piston please.
 
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I'm correction part of my comment. I just pulled out a block and put a head gasket on it. I failed to consider the recessed area of the gasket for clearance of the intake valves. That's probably what I thought was the piston ring. But the edge of the piston still doesn't look right.
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