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Discussion Starter #1
Hi , I started today looking for the reason I have 14psi difference on my compression readings. I popped out the plugs and took the exhaust manifold off to peek inside.
There was no scuffing on the cylinder walls so I stuck a finger in the combustion chamber to see how much side-play the pistons had. I was kinda suprised at how much there was. (the sled has 3K miles) Then I noticed that the piston with lower compression has a dishlike depression on top, and the other piston is domed on top.
I guess my question is, How much side play should I have , and is this what you call melting a piston?
The plugs on this sled are nice and tan, and it rus like a top.
Also, what causes meltdown like this other than a leaned out carb?
Any help is really appreciated.
Thanks, Don


Who ever dies with the most toys wins.

[red]Moved to The Shop by Polaris-Man[/red]
 

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Sounds like the piston melted, and it's caused by a leaned out carb
It's can also be caused by a plugged exhaust port or lack of lubrication, such as an oil restriction.



"Might Be Crazy But I Ain't Dumb" - Cooter
 

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You could also have a air leak in the base gasket, head gasket, crankcase, or oil seals. That would cause a lean condition as well.
 

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Discussion Starter #4
Thanks Guys,
I`ll go home this evening and pull the top off the engine and start my rebuild process. I`ll also give all my seals a good looking at.

Who ever dies with the most toys wins.
 
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