4 or 2 cycle

[Davelabelle]

I have inherited a 1964 Evinrude 40 hp outboard with no manuals
or previous owners instruction. Is it a 4 cycle (straight gas) or
2 cycle ( pre-mix)? If it's a 2 cycle does anyone know the mix ratio?

 

[tx1961whaler]

Re: 4 or 2 cycle

2 cycle
50:1 TCW-3 outboard oil
87 octane unleaded gas

 

[Chris1956]

Re: 4 or 2 cycle

You need to premix oil with the gas for that motor. Use the 50::1 mix as was recommended.

BTW there were only 1 or 2 manufacturers of 4 cycle outboards back in the 60s. Homelite was one of them. The big three (Johnson, Evinrude and their "relatives" and Merc ) were all 2 cycle.

 

[Silvertip]

Re: 4 or 2 cycle

For anyone else reading questions like this one -- It is so simple to tell a four stroke from a two stroke. If the engine has a crankcase with a dipstick and an oil cap on the engine block (like your car) to check the oil it is a four stroke. If there is an oil tank on the side of the engine and the cylinder head is flat as a pancake with spark plugs in the middle you have an oil injected two stroke. If you have a similar looking engine with no oil tank is a pre-mix two stroke. In 1964 there were few four-strokes. In the more modern era, the engine generally has a decal on it stating that it's a "Four Stroke".