fuel mixture 1960 40hp johnson

[mikeaga]

I purchased a 1960 Orlando Clipper with a 40 hp Johnson. I just got it back from the mechanic. He says to mix the fuel 3.2 ounces of oil to 1 gallon of gas. Is this correct? I ran it and it smokes alot and seems to not run quite right. I was using an old metal gas tank. Any thooghts would be appreciated. Thanks ,Mike I would add a pic if I new how.

 

[Joe Reeves]

Re: fuel mixture 1960 40hp johnson

You're going to have three dozen people jumping in here with all kinds of warnings and various fuel/oil mixtures.

That engine has either roller, needle, or ball bearings on all of its internal moving parts. And as such, it is perfectly safe to use the 50/1 mixture..... One pint of good quality 50/1 oil to 6 gallons of gasoline. A gasoline octane rating of 87 will be fine. Trust me.

 

[bouttime007]

Re: fuel mixture 1960 40hp johnson

You may find 50/1 works fine, and it will run fine on 24/1 like originally intended. Ive run closer to 40/1 for awhile in my 1962 28h, and have had no issues.

To each his own is my way of thinking. Oils have come a long way in 50 years.

 

[tx1961whaler]

Re: fuel mixture 1960 40hp johnson

Somewhere between 24:1 and 50:1.

 

[1946Zephyr]

Re: fuel mixture 1960 40hp johnson

24:1 on bigger motors 64 and earlier. If you do run 50:1, make sure your cooling system is right up to parr. If your motor gets hot, it will nuke the pistons out sooner with lesser oil. One thing I can be certain of: Oil is the cheapest thing you'll put into an engine, and you'll never harm your engine with a little bit of oil.

 

[mikeaga]

Re: fuel mixture 1960 40hp johnson

Thanks for all the input. I am thinking somewhere around 42.5:1 should be good. lol

 

[JB]

Re: fuel mixture 1960 40hp johnson

24:1 is what OMC said. 24:1 is what BRP says. I know of no official publication that recommends any mix leaner than 24:1.

Joe Reeves is correct about the "frictionless" bearings and it is probably safe to run 50:1, but I believe there are reasons that even BRP tells us to run 24:1.

If it were my outboard it would be running 24:1.

 

[1946Zephyr]

Re: fuel mixture 1960 40hp johnson

Yep, I totally agree with JB. Oil is the cheapest thing you'll ever put in your engine. Number one being it's only a couple ounces more than 50:1 and number two, it'll extend the life on your outboard, saving you costly repairs. Skimping on oil on an outboard is just not worth the end result. A fouled plug is much cheaper to replace, than a scored piston......and much easier too.