Advice please-oil for old 2 stroke engine

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

Reply to
etpm
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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.

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.

Reply to
Ed Huntress

=========================== Given the much better lubricating qualities of the new synthetic two-stroke oils, minimal smoke, and the small amount you will be using, why not buy the good stuff?

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I used Castrol in my Vespa and Aero 150 I had for campus commute with good results.

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Reply to
F. George McDuffee

So the experts you spoke with all say to go with modern oils. That's what I want to to but I was reading on some antique outboard sites and several guys have said that modern oils will not lubricate properly plain bearings-that the oils are made for rolling element bearings. But even though the modern oils are made for bearings that work best with a very light oil film the piston and rings are not rolling elements so the oils must work well in shearing too. I could go with the old type oils but I want to use modern oil because I think they will work better. Eric

Reply to
etpm

On Saturday, January 31, 2015 at 4:12:26 PM UTC-5, snipped-for-privacy@whidbey.com wrote: I think I

Two stroke oil has less ash than plain 30 weight oil. So better on the eng ine.

Exxon Mobil is an excellent company and is generally regarded as having mo re research into oils than other companies. So I would buy Mobil 2 stroke oil, at loast if you can easily find it. In any case I would buy a oil tha t meets API tc. Mobil makes three grades of two stroke oil. They all meet API TC.

Dan

Reply to
dcaster

Might peruse this thread:

Jon

Reply to
Jon Anderson

Was Gargoyle/Mobiloil A a castor-based motor oil?

I'd likely use a new castor oil like Husky and Stihl put out, or a new synthetic like Royal Purple or Castrol, were it my engine. I always favored the castor oils my friends used in the old Combat Wombats, partly because of it's high film strength, and partly because of the wonderful smell when it's burnt. It's the 2-stroke version of the NitroMethane Smell(tm). Better than napalm in the morning.

Or combine the best. Maxima 927 is a blend of castor and synth. I think maybe I'd give Maxima a try.

Reply to
Larry Jaques

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