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Piston to Cylinder Bore Play

Wez_

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Before finalizing my top end assembly, I gave the pistons a wiggle in the bore only to find some play in the # 4, 3 and 2 cylinders. Number 4 has the most, and it gradually gets tighter across the block ending with Cylinder # 1 with no play at all. Just 2-4

What do you guys think?? Should I remove the cylinder block and recondition it? I do not have a cylinder bore gauge...Any thoughts?
 
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The top of your pistons will always move and be looser then the skirt, pistons are tapered and get tighter at the skirt. You cant judge piston clearance by how the top moves you have to take the pistons out and measure the skirt and the cylinder bore to know what your clearance is.
 
X2, not only are the SKIRTS tapered but the top ring section is undercut to be about .020"-.030" looser than the skirt, it's GOING to wobble to freak you out.

Again, the only way to check is parts apart, although you can get some idea by looking at the top of liner right above the top ring stop point, the ring groove wear. The carbon deposited above ring will make that appear worse.
 
OK, thanks guys!! I had to let that sink in for a day. It makes sense.

A co worker let me borrow a leak down tester.
Would it be a bad idea to use the old head gasket and do the leak down test, The metallic OEM head gasket did have some layer deterioration along the edges in some spots, but near the bores it appeared nice.

If that's a bad idea, then I should use the new gasket and do the leak down test. It would be nice to be able to use the old head gasket for a leak down test and if it passes, then go with the new gasket and close her up.
 
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