OPS .65, piston/liner condition
Got one OPS .65 in the mail today, this one was listed as having been run about 10 times and I was told it is tight on top. I disassembled it today and all in al it looks okay inside at least, and it was evident there was a lot of castor in the fuel it was run on.
Right mounting lug looks like it got caught fooling with another man's flight box, been beaten on a bit, but I can clean it up.
Here is what I see with piston liner fit, how does this sound:?
Piston has some carbon on top, perhaps 10 mils at the thickest spot, but clean around perimeter other than near exhaust port. Oh boy I thought, someone from the old school of "bullst, run 'em slobbery rich" got their misguided hands on another fine Italian engine and f-ed it up on the first runs. But the fit is as follows: if I support the piston by the conrod and let the crankcase and sleeve weight slide down on its own, it gets to about 1/8" from the top of the sleeve. With some finger pressure it reaches about 1/16" frm the top, and with a lot of finger pressure I can get it just about flush with the top of the sleeve. Note it is well lubed with residual castor oil and some preservative too it seems. It takes a bit bit of a push to get it free and back into a downstroke. But I don't feel a "squeak", just lots of resistance. I guess this is the film of castor spooge doing its job?
This one has a Perry carb, I want the OPS carb instead. Have to see if I can find one identical to the other. I can use the Perry elsewhere if it works.
MJD