Hi,

Can you identify this engine? It doesn't say anything on it at all except "OK".

Thanks!

It's a Herkimer OK made in various sizes thru the 40's, 50's, and 60's by the Herkimer tool company. .049's thru .35's and maybe more. Believe they even made a twin ignition engine back in the days of the dinosaur...........RJ

Thanks.

I also had someone say that this is an "OK Cub Twinstack".

Is that the same thing?

It looks like an OK Cub 29 or 35 made in the 50s. As I recall they used a ball and socket connection of the rod to the piston like their 049s. The engine was pretty much a failure because of this. The ball and socket just was not adequate for engines this size.

Denis

Yes, the smaller ones were called Cubs. I'm not so sure about the larger ones as I never owned one. The first RC plane I ever flew (1955) was powered by a Cub .074 diesel. Still out in the garage in the old engine box. [8D][8D] RJ

With your help, I've narrowed this engine down to two choices:

It's a Herkimer OK Cub, and either a .29 or a .35 made in the mid 50's.

Please tell me how I tell the difference between the 29 and the 35.

I measured the diameter of the piston. It is 0.7 inches. Is 0.35 the radius of the combustion chamber/piston?

I had someone tell me that the 29's had red trim and the 35's had gold.

Thanks!

Bob

The Anderson book says that the .29 (Red Trim) has 8 cylinder fins & the .35 (Gold Trim) has 9 cylinder fins . I would buy yours for parts . MAX H.