Piston clearance?
Thread Starter
Pro
Joined: Dec 2002
Posts: 522
Likes: 3
From: Rolling Meadows IL
Piston clearance?
I got the heads off my 85. The cylinder walls look good. I can still see
the cross hatch and there is no ridge. I can get a .015 feeler gage
between the piston and the cylinder wall when the piston is about half way
down. :confused: Are pistons the same diameter at the skirt and at the top? Is it normal to have a gap between the top of the piston and the cylinder wall?
the cross hatch and there is no ridge. I can get a .015 feeler gage
between the piston and the cylinder wall when the piston is about half way
down. :confused: Are pistons the same diameter at the skirt and at the top? Is it normal to have a gap between the top of the piston and the cylinder wall?
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Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Re: Piston clearance? (dave_85)
The dimension you are checking is meaningless. The piston is measured at 90* to the pin, as mentioned, at approximently pin height. Usually the piston is miked, and the bore checked with a dial bore guage. I think your '85 has the same forged pistons as my '84. The "production clearence is, .0025" - .0035", with a "service max" of .0045". Cast pistons are clearenced, much tighter than this. It IS possible to verify from the top with feeler guages, but not with the rings installed. Good luck, and...
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