Real scoop on 2 cycle oil

Maybe one last question on this thread ??? I have an old outboard motor - circa 1964 or so. I remember when I was a kid, I had to add 1-qt/6gal tank. I’ve wondered since if I could go to the 50:1 ratio. My sense is the answer is, “No.” But… I never tried using the 50:1 oil. Thx…

Each machine will have its own ratio. You should stick to the 1 quart per 6 gallons formula.

johnny; your old outboard was designed for 12:1 ratio gas/oil (1 quart/6 gallons), and the engine tolerances, etc were such that this ratio was necessary! Oils have much improved since then, but I would be very hesitant to much more than, say a 16:1 or 20:1 at most.

I worked for these people in the sixties and we had just gone to 50:1 on the new 100 HP outboards. The older ones retained the old ratio. My 1986 Lawn Boy states a 32:1 mixture, and it says not to use automotive oils (too many addtives) or use gasohol of any kind!

PS: Sorry, 1qt/6gallons is 24:1, and you could go to 30:1.

I believe that 1 Qt to 6 gal. = 24 to 1. ( 6 gal. is 24 qts.) As Docnick says, engines have been improved much since then so the older engines should probably need more oil.

If you want to keep your old motor running keep using the specificed mixture ratio. As motors developed and oils improved the ratio’s were changed and newer motors can use 50 to 1 ratios no problem. You motor is an oldie. To keep it a goodie it needs lots of lubrication, stick to the original ratio for the mixture.

Dang good thing he didn’t call it a “two cycle motor”.

You are RIGHT!! Those old 16-1 and 24-1 pre-mix engines generally had BUSHING wrist pins. Only after they went to needle bearings on the wrist pins and designed oil traps in the crankcase to keep the oil in the engine better, THEN they allowed 50-1 and eventually 100-1 mix ratios. At that time the greatly improved TC-W outboard oil came on the market…

ahahahahaha! is enough…ahahahaha

"Darn, I wish I was as smart as your are! "

Sounds like a two stroke reply…gruff, to the point, offensive, highly polluting and much more harmful to the cordial web site environment.

A great book, “Polluting for pleasure” put two strokes in their rightful place as a compact power house at the expense of our environment. I believe it was a catalyst for the legislative action based on the revelation that much of that oil you mix with the gas, isn’t burned, but finds it’s way into our lakes and steams. I still have them and use them, but try to limit their use in and around the water. And yes, any TCW3 approved oil seems to work for me well in any two stroke application.

There are two basic categories for 2-stroke oils and the difference is mainly in the additives.

  • Low ash - which is for high temp, air cooled engines and meets the API-TC specification or others
  • Ashless ? low temp operation in water cooled engines such as outboards, the latest spec here is TCW3