I'm rebuilding a 91 Johnson 40 -- top cylinder connecting rod bearing failed. I believe it is a loop scavenger type 2-stroke engine because the piston tops are flat.
This engine has obviously had a rough life because the top cylinder head has a bunch of dings in it which must have been caused by a piston disintegrating in an earlier failure before I bought it. The dings are on the flat part of the head over the cylinder, not in the domed area.
My question is whether those dings can interfere with the proper flow of gases through the combustion chamber in this type of engine? If I can find a use head without dings should I replace it? Or is it unlikely that the dings are affecting anything?
This engine has obviously had a rough life because the top cylinder head has a bunch of dings in it which must have been caused by a piston disintegrating in an earlier failure before I bought it. The dings are on the flat part of the head over the cylinder, not in the domed area.
My question is whether those dings can interfere with the proper flow of gases through the combustion chamber in this type of engine? If I can find a use head without dings should I replace it? Or is it unlikely that the dings are affecting anything?