On Sat, 31 Jan 2015 13:12:39 -0800, wrote:

I have an engine that's nearly 100 years old. It is a two stroke water
cooled made by Cady. The oil type for it that's stamped on the brass
label is Gargoyle/Mobiloil "A". The mix ratio is 1 pint per 5 gallons.
This one cylinder engine has grease cups for lubricating the babbit
crankshaft journals. The connecting rod is bronze. The rod is the
bearing for both the wrist pin and crank throw. The piston is cast
iron, with cast iron rings, and runs in a cast iron bore. I think I
can just use non-detergent 30 weight motor oil but am wondering if a
modern two stroke oil would be better. Opinions anyone?
Thanks,
Eric

Totally unfounded opinion follows: I have an Ohlsson & Rice two-stroke
bike engine that's nearly as old as I am -- yes, it really runs on
gsoline. g

I had the same question. I asked around to some 2-stroke experts and
they agree that I should use modern 2-stroke oil. I followed Briggs &
Stratton's recommendation. They recommend 50:1 for newer 2-strokes,
and 32:1 for old ones.

I fudged a bit and run it at 25:1. It runs great. It smokes, but not
very much. But I don't have enough hours on it to tell if I'm grinding
up the insides. I think not.

Disclaimer: If it fries your engine, don't blame me. g

--
Ed Huntress