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Starting to do first engine rebuild

Finally took the head off Smokey the other day as the radiator had to come out for a recore.
Notiched large visible gap between pistons and the cylinder walls ( able to fit .010" feeler between )

Measured the cylinders and they are ranging from 2.247 to 2.252. The good thing is there is no visible scoring down the side of the bores.
As cylinder 1 is the worst do I need to look at having the block bored out to 60th?

Bryan

Location: Whangarei New Zealand

Re: Starting to do first engine rebuild

Hi Bryan

I take it you are measuring skirt clearance and not the top land!

I presume from the variation and the skirt clearance that the bores are +.040 worn 047 to 052 at the tops below the lip or where lip has been removed. Such wear is rare nowadays but common to the 1950s prior modern oils. Nevertheless .010 skirt clearance on thrust sides is a lot suggesting collapsed split skirt pistons (or an engine poorly assembled from oddments). Presumably it is less at bottom of stroke.

The exact worst worn spot can be hard to find with a micrometer or expander gadget.
usually just below top ring limit.

A deglaze hone (or sandpaper on bobbin) may reveal any porous spots in the bore.

If the bores are all .047 at bottom and about 052 at top not so serious, but .010 skirt clearance excessive and unlikely to find pistons that fit odd oversize directly.
(+.120mm??) Size usually stamped on piston.

Location: Auckland, NZ