Correct Ratio

[denblaq]

Does anyone know the correct gas/oil ratio for a 1963 Mercury 500 50hp outboard ? Is it 50:1 or 24:1
Thanks, Denis

 

[Capt Ken]

Re: Correct Ratio

Back yonder they were doing 24:1. Fouled a lot of spark plugs.

 

[Georgesalmon]

Re: Correct Ratio

was 24:1 back in the day. quart oil to 6 gal gas

 

[Capt Ken]

Re: Correct Ratio

Seen the inside of many an old motor and don't see why running 50:1 wouldn't be a problem with the newer more advanced 2 stroke oils on the market now. Lots of difference from the old oils of yester years.

 

[coolguy147]

Re: Correct Ratio

http://forums.iboats.com/engine-fre...-oil-mix-most-motors-covered-here-158072.html

I believe it's 50:1

Although, I always ran 24:1 in my 1961 mercury 500. Ultimately, the choice is yours.

 

[steelespike]

Re: Correct Ratio

My aftermarket service manual covering Merc 4 and 6 cylibder outboards1955-65.
It says Mix 12 ozs Formula 50 Quicksilver( assuming todays TCW3 rated oils meet these specs) outboard oil with each 5 gallons. Thats less than 50:1 2.4 ozs per gallon.
I would stick with 2.6 ozs per gallon.Again assuming the TCW3 oils meet the same standards.
You might go to johns old mercury web site and ask if todays TCW3 rated oils meet the same standards.
I can tell you My 65 Merc 500 has run on 50:1 all its life.

 

[64osby]

Re: Correct Ratio

Ran my 67 Merc 500 on 50/1, always made it a little heavy on the oil, just to make sure.

 

[tomhath]

Re: Correct Ratio

I had a Merc 350, circa 1960. Called a Merc dealer and they said to use 50:1. It's really the oil rather than the motor that determines the mix.