Fuel Mixture

[SlickWillie]

I'm in the process of getting my Dad's old Mercury 9.8 back in running condition. I believe it to be a 1968 year model. Serial #1982433. I'm unsure of the gas/oil mixture. The original tank rusted out years ago, and the mixture was printed on it. Thanks for your assistance.

 

[rickdb1boat]

Re: Fuel Mixture

50:1 would be the correct mixture. 2.65 ounces TC-W3 oil per gallon of gas...

 

[ZmOz]

Re: Fuel Mixture

I would just go with 3 ounces and about 40:1. A little extra won't hurt anything, and that motor was designed to use probably at least 32:1 if not more...

 

[rickdb1boat]

Re: Fuel Mixture

1966 Model<br /><br /> Year and Parts<br /><br />I thought all those Mercs ran a 50:1 ratio, but I guess it wouldn't hurt to get a little more lube in there..

 

[dilligafda]

Re: Fuel Mixture

You are correct rick, 50:1 is the correct ratio, but with an older engine like this, 40:1 won't kill it.<br /><br />Good luck!

 

[Darryl34]

Re: Fuel Mixture

I used 40:1 in my 1971 115.Has never done any harm.20 litres to 500ml canadian

 

[SlickWillie]

Re: Fuel Mixture

Thanks for the info. I pulled the engine cover, and found scribed on the top of the pull rope assy. (oil 6 oz. per gal). A little better than 20:1 if I figured it right. Seems like a lot of oil to me. Think I'll go with the 30 or 40:1 mix.