what whould be exceptable clerance between piston and cylinder on a 239
I just took a 239 apart and ther is a lot of space between them I have a set of 30 thou over pistons that seem to fit good
I should mention that the moter had no compresion that is why I took it apart
could be someone,s quick sell fix?

 

Time to get out your caliper. The shop manual shows the max manufacturer's bore diameter as 3.1899 or clearance between piston and cylinder wall as .0099

.030 over would make your pistons 3.210 plus .0099 makes 3.2199" If your bore is in that neighborhood you should be good. Remember if you're too close to piston size that expansion occurs with heat from combustion. Rings should have about .015" end gap when installed.

 

thanks tim just what I needed to know
I will mesure them up today
with any luck I might have a running truck soon.

 

there,s no way a set of 030 pistons will fit in a stnd,bore.are they going all the way down.if they are your block is oversize.