Hello All:

I have been attempting to lap a contra piston to a cylinder with little success. I spent a few hours yesterday pushing the contra piston into the cylinder while both were coated with an abrasive. I seemed to make no progress.

I started with Dupont red polishing compound but gave up due to making little progress. I then switched to an 800 grit abrasive that was supposed to be the answer. After many trips of the cp through the cylinder, I again gave up due to no progress.

My method is as follows:

Coat the inside of the cylinder with paste of oil and abrasive.

Coat the cp with a coating of the abrasive paste.

Push the cp into and out of the cylinder using a large vise and wooden dowels.

Stop and clean the parts with hot water, soap, toothbrush, spray with WD 40, spray with carb cleaner, lightly oil and check for fit.

I repeated this routine many times but I have not seen any change in the fit of these parts.

Is it time to switch to a piece of fine wet and dry paper wound on a dowel to get things started to a point where I can begin to lap the parts together. Once he cp goes past the top of the ports, it becomes very difficult to move! I takes a considerable force to move the cp!

Oh yes, the piston is also tight in the cylinder but that is the next dilemma.

Is there anybody to whom I may send this engine to have the parts fitted?

Suggestions?

Be well my friends,

Fanchi