Thanks everyone. The engine is a Kohlor K161 and the blue paint is optional ! Ha Ha. I think it is the original engine. I don't know if the paint on the whole tractor is original or not but it looks to be pretty good. If you guys think its a '57 then that gets me woundering if one of the other Ride-a-matics I have is really a '57. Or is it a '58 maybe. Thanks again for the help. Parry
I agree with the others. ...It appears to be a 1957 model.
Your tractor appears to be a Model 21HD-01 Super Ride-A-Matic with 6.6 hp Kohler. .....The original engine was a K-160, as Brian mentioned. .....The blue color of your engine was the color that replacement Kohler engines wore. .....The original engine would have been green to match the tractor color. ....The larger-diameter fiber reverse disc was mounted on the variable-speed pulley.
There was also a model 20HD built in 1956-1957, but these came equipped with a 3.6hp Kohler K-90 engine. ....These tractors used a small-diameter reverse disc mounted on the engine pulley.