'57 Lightwin Fuel/Oil Ratio

[1stgenbird]

Trying to find the best ratio for fuel/oil for my motor. My old Evinrude factory service manual specifies 1/3 pint per gallon which is 24:1 but the decal on the front of my outboard calls for 1/2 pint per gallon or 16:1.

Both specify the oil as SAE 30 as that what was used back then but I'm thinking that with the new oil I am safe with 24:1.

 

[wbeaton]

Re: '57 Lightwin Fuel/Oil Ratio

16:1 with SAE 30W automotive oil was the original ratio. With the invention of modern TC-W outboard oil the ratio was revised to 24:1. Some will say to still use 16:1. Not me. I use 24:1 with synthetic TC-W3 outboard motor oil.

 

[JB]

Re: '57 Lightwin Fuel/Oil Ratio

In 1964 OMC changed it to 24:1 using outboard oil (now TC-W3). That worked for about 50 years.

Recently there have been publications that say it should be 16:1 or 20:1. If 24:1 was bad for them they would be long dead by now.

I am with wbeaton. 24:1, 87octane and TC-W3.

 

[firstboatbuild]

Re: '57 Lightwin Fuel/Oil Ratio

I agree 24:1 with 87 oct and always you Stabil for ethonal fuels.

 

[1stgenbird]

Re: '57 Lightwin Fuel/Oil Ratio

Thanks. 24:1 is what I will be using, same as my 57 Fastwin.

I have not been using Stabil but have been adding Seafoam to the gas in all my outboards.

 

[scipper77]

Re: '57 Lightwin Fuel/Oil Ratio

I agree 24:1 with 87 oct and always you Stabil for ethonal fuels.

If your fuel will sit you do not want 87 ethanol blend. The ethanol in the gas has an octane of 113. So to make the average octane 87 the gas has an average octane of around 84. If you get phase separation and the water in the tank isn't enough cause problems you will be running with too low of an octane. I personally go with 89 octane.

Here is an article on everyone's favorite subject.... Ethanol. http://www.fuel-testers.com/gasoline_octane_and_ethanol_E10.html

(I will not post any further on fuel to avoid turning this into a "fuel thread")

 

[wbeaton]

Re: '57 Lightwin Fuel/Oil Ratio

If it separates, the amount of octane will be a moot point.

 

[1946Zephyr]

Re: '57 Lightwin Fuel/Oil Ratio

Oil is the cheapest thing you can put in your outboard. Cheap as in dollars and cheap as in prolonging the life of your classic and preventing premature wear. I would stick with 16:1, but that's just me.