Automotive oil in outboards

[captglm]

I was talking with my brother in law about outboard oils, he told me he runs automotive oil in his 9.9 outboard mixed 50-1. to say the least it surprised the heck out of me. he said he's been doing it for years with no problem.

GM ><>

[SSRACER]

Early outboards ran on 30w mixed in the gas.

[stray cat]

Yeah... I remember my old Evinrudes one quart of non detergent 30 weight oil for every 6 gallons of gas. Smokin old bastards.:thumbsup: Couple of em are still runnin.

[wrechin2]

That is all they used to be. There wasn't a special outboard oil. Worked well back then. Guess they smoked alot more on that oil like stray cat said...

[Mark75H]

Early outboards ran on 30w mixed in the gas.

Very true. There was a lot of trouble with carbon build up and spark plug fouling. Carbon on the rings will probably eventually get this guy's brother-in-law and cost him more than the difference in the price of oil.

[Bruster]

Why??


I was talking with my brother in law about outboard oils, he told me he runs automotive oil in his 9.9 outboard mixed 50-1. to say the least it surprised the heck out of me. he said he's been doing it for years with no problem.

GM ><>

[jody504]

The old people us to use them and knew how to shack the hell out of the tank befor take off. It does work but if you want to save money don't go fishing are get a real old motor like a paddle no oil are gas.

[Forkin' Crazy]

Very true. There was a lot of trouble with carbon build up and spark plug fouling. Carbon on the rings will probably eventually get this guy's brother-in-law and cost him more than the difference in the price of oil.

I was thinking the same thing. Seen many motors come through my friends dealership with stuck rings. And they were running cheap two stroke oil in them. I could imagine what 30wt would do.

[j_martin]

I have an old (1928) graham-paige roto-tiller that has a 30 cid 2 stroke engine on it. Fuel/oil mix on it is 16:1. 30W non detergent is the specification.

I run 16:1 TC3 oil in it. Never have a problem.

With motor oil, I'd better have a spare plug and wrench in my pocket.

[Jeff_G]

Early outboard oil, through the 1970's at least was pre-diluted 20W. As J Martin said the old motors were usually at 16 to one. Modern engines all require newer formulations for Two Cycle Water Cooled. Use of non certified oils can cause a lot of undesired results.
If your friend insists on using car oil he is just being stupid. Ask him if he lubes his bearings with whale oil too.