Model Forum / Radio Controlled / Air Models / March 2008

Ted,

It seems that the 61SF manual isn't available as a .pdf download anymore. As
I recall the 61 SF was available in both ABC, and Ringed versions. You will
need to remove the muffler, and look into the cylinder (through the exhaust
port), while turning the crankshaft by hand. Look for the presence of a
piston ring ,at, or near, the top of the piston. You will need to know which
version of the engine you have, should you ever need parts for it. The time
to check is now before you mount the engine in a model.

I can tell you that it was a very well designed, long lasting, and powerful
engine. If I had the choice today, between buying a new never run 61 SF, or
it's current replacement in the OS line. I would take the SF, as I believe
that it is a higher quality engine than it's replacement.

Ken