Size of 3/8 pistons

[Kurt in NJ]

I am going out to play soon, i will drag it out and take some pictures ---as to a "sonic test" finding a pinhole corrosion pit I don't think so except for luck the way I saw the test being done at a local shop---3 spots on the bottom, 3 spots on the top of the bore----perhaps other testers are better but to find a 1/64" corrosion pit it looked like it would take a long time going over every 1/64" of the cylinder walls

The walls are greased. I will clean them, get better #s, perhaps I will only need 1 special piston