1969 Johnson 20hp boat motor,model # 20R69D. What is the fuel mix ratio?

Question

I recently aquired a boat with a Johnson 1969 20hp motor and have no idea what the fuel mix ratio is. I want to be sure before I start it and there are no manuals that came with it. Is it 50:1?

Answer 1

Probably 25:1 for that vintage

Answer 2

50 to 1.  Been using this in my 69 since 69 and it's still going.  Any lower ratio than this is either fouling the water or plugs.

Answer 3

50:1.  OMC changed from 24:1 to 50:1 in 1964.

Answer 4

50 to 1 is a safe bet on anymotor. especially so on older or worn motors. If you run 50-1 and get oil fouling of the plugs, drop it back a little.

Answer 5

40 or 50 : 1 will work.... make sure it smokes just a little and you will know all is well...

Answer 6

hi there

you should most definitly use a 50:1 mix J/E changed to this ratio in the 60's and was the best thing they done. A good general rule of thumb to remember the ratio is to figure 1 pint 16 oz. of oil to  6 gallons of gas. Also you want to put oil in tank first to make sure it is mixed up with gas properly. Hope this helps u out.