An additional thought here is that the compression rings and oil control rings may have different wear values. .
Harry Converting a C-85 to a C-75 Are there any provisions to take C-85 to a C-75 since the application that I'm using it on requires a C-75-12.From the practical operational standpoint, impulse coupled magnetos are the only way.Harry Running Rich on Just One Side My C150 G is the reason for manual for honda civic 2004 asking for help.In practice, most overhauls done by enthusiasts or as hangar overhauls not done by a shop will use the old, but cleaned up, hardware.Unless you are operating in a highly humid environment, plain steel cylinders will work well.
When the C-85 piston is used with the O-200 crank, the piston travels further up into the combustion chamber. .
The valve mechanism has a couple of critical components which can affect engine performance at all rpms: The valve and the hydraulic unit which is part of the mechanism which pushes the valve open. .It is normal to see some strike lines from FOD going through the pump, but if the surface is marred too much, this will increase the edge clearance between the gear and the pump well walls.Well, actually I do know what he did.Undersize and Oversize Pistons and Cylinders The original questioner here had a variety of cylinders to build up his engine with.All I need to do is increase the RPM to 1000 RPM and the pressure comes up to 15 psi. .The key to my success was that I had always used new parts, both pistons and cylinders- and was lucky on the stack-up.Run a 3200 takeoff rpm prop and cruise at 3000.If the engine does not cut off when the mixture arm is pulled to the cut off stop, then there is a problem internal to the carburetor and it needs to be repaired. .The only thing I did to the aircraft between Saturday and Sunday was put fuel. .
Magneto and carb heat drops appear normal.
However, this is the way the Cub has always been for 75 years, so some sort of solution must exist. .