What oil for old outboard

[heavyhitter]

I was given an old Lund with and old Johnson outboard, if I recall I believe it is a late 1960's 18 HP. It was my wifes Grandfathers fishing boat. The gas in it is 12 years old. The fuel lines are dry rotting and so are the tires. My brother inlaw took it out a said it ran fine, I would rather that he did not run the 12 year old gas through it! But apparently it started after many many pulls but after the initial start it would start on the first pull the rest of the weekend.

I plan on getting new tires, fuel line and fuel tank. I picked up a quart of Johnson brand 2 stroke oil about 5 years ago when I was gonna take it out but never did.

What type 2 stroke oil should this take? What mix ratio? Ofcourse non of this is written on the motor anywhere.
Do you think the unopened quart thats been in my garage for 5 1/2 is still good?

 

[bepperb]

Those are good motors. I'd need the exact year of the motor to tell you. 24:1 doesn't sound too far off. Older outboards take the condensed oil from the crankcase and vent it out into the coolant outflow (very bad) so they need more oil. In the late 60's they began to scavange this and route it back to the carb, so there is a lower ratio for those. If you have time, you'll enjoy this reading:

http://www.duckworksmagazine.com/06/columns/max/index6.htm

Which is very similar to what you're running.

I'd replace the impeller, which will run you about 20 bucks and an hour of time, and change out the lower unit lube, which will be another 3 bucks and five minutes. Two spare spark plugs seem like a good investment as well.

Any TCW3 oil will be fine in that. What you have will be fine. What is the serial of your motor?

 

[heavyhitter]

I will have to look for the serial number on it. The boat is kept out in a barn on my inlaws farm 60 miles away.
Thanks for the link.

 

[expat]

You do not want to used Ethanol blended gas with this motor, the float in the carburettor is made of Cork sealed with shellac. Alcohol will dissolve the shellac and block the carb jets.
The Carbuettor is Very simple, it may be worth dismantling and cleaning it.
If you work carefully you can get by reusing the oil gaskets.

 

[bepperb]

Good point Expat. I'm not sure when Evinrude/Johnson made the switch. Definitely before the mid 70's, so maybe in the late 60's but I don't know. I've seen epoxying, and you can usually find a new float it that's a concern where you live HeavyHitter.

When our 50's 5.5 was converted to a fuel pump/single line, whomever did it was nice enough to convert the float for whatever reason.

 

[BUBBA0420]

Use any TCW-3 Oil and as said above no ethanol gas
I would mix it at a 32:1 Ratio. You can run a little leaner
than the original 24:1 but I wouldn't go to 50:1 with it
Also use 89 octane gas not the 87

 

[heavyhitter]

Thanks for the advise all.
Where I live only 87&91 are the only non eth blend. ALL of the 89 is ethenol and the cheapest.

I never run ethenol blends in anything but my cars.

 

[FastSUV]

Pennzoil XLF seems to be the oil targeted for your application