Outboard oil in an air-cooled engine??

[guy48065]

I may be misinformed but I've always been told that outboard oil is specially formulated to not gum up at the lower temperatures typical of water-cooled outboards. Don't use chainsaw oils, etc. But what about an air cooled outboard? Isn't that more like a chainsaw? For older engines like mine (not sure of date it's a mariner 5M sn 661 034994...manual is dated 1979) the manual says to use basically any old 2-stroke engine oil.

I prefer to run synthetic but if I don't have to run expensive outboard synthetic, then great.

 

[Yepblaze]

Re: Outboard oil in an air-cooled engine??

Oil schmoil.

Every 2 stroke here, and theres a &%#$load of em, get Penzoil Premium Synthetic Blend Outboard Motor Oil from Walmart at about $10 a gallon.

The boats get 50:1 and the aircooled stuff gets it at about 32:1.

The oil injected motors, air or water cooled, love it straight.

I amaze myself when I'm tossing out a couple empty gallon jugs, or a 2 1/2 gallon one when I stop to think how much gas I had to burn to use that much.

Oh and most of those motors are run hard for extended periods. (lately in 100+ heat)

 

[mthieme]

Re: Outboard oil in an air-cooled engine??

It a Mariner and they didn't recommend Quicksilver ?
Every manual I have recommend whatever oil the manufacturer sells.
odd.

 

[Joe_the_boatman]

Re: Outboard oil in an air-cooled engine??

I've always read that the oil for air-cooled two strokes is formulated so it won't break down at the higher temps that those engines run at.

Regardless, the last year's marine mix always ends up in my leaf blower. I add some air-cooled oil to it though just in case.