Cylinder base studs

[chrisx1]

What thread size are the Nuts that hold the cylinder barrel down on an A65.
1968 A65L

Im thinking 5/16 24 UNF but would like verification.

I want to clean the stud threads up before reassembly.

[Allan G]

There shouldn't be an UNF/Unc threads on a 68, it will be cycle threads for the nuts and BSF into the crank case. I wouldn't remove them unless you need to.

[chrisx1]

I don't want to remove them I want to clean the threads in situ.
Any one know what cycle thread size they are?

[Allan G]

5/16