Fuel/Oil

[Jetjohn]

I know this is basic 101, but I need to find out. Just bought an old Johnson, and need to know, is the proper gas/oil mix 50:1 ? I think its 1 pint of oil to 6 gallons of gas. Please don't laugh at me, we all started out with no knowledge.

 

[Terry H]

Re: Fuel/Oil

Which old Johnson you talking about. In the '60's and before they were made to run a diferent mixture, 24:1 I think. Tell us what motor you have and you will get an accurate answer. Chief

 

[roscoe]

Re: Fuel/Oil

Even older motors ran on 16:1 mixture.<br /><br />Please post hp, model, and serial number.

 

[Scaaty]

Re: Fuel/Oil

From "Chinewalker" as stated in the FAQ's section.......<br />POST-1964 JOHNSON/EVINRUDE/GALE - The official stance on 1964 and newer OMC engines is to run them 50:1 and it's a good rule of thumb to follow on the bigger motors. OMC also renegged on the late 1980s 100:1 recommendation on the smaller (4-35hp) motors, bumping them back to 50:1. I've found that the smaller (3, 4, 5, 6hp) motors from post 1964 up into the mid-1970s may appreciate a bit of extra oil as they still have some bronze sleeve bearings. I run 40:1 in my '72 4hp, as I have a pile of holed blocks, burned cranks and twisted rods that were run at 50:1.<br />1960-1964 JOHNSON/EVINRUDE/GALE - 18hp and up can run at 40:1, as they are mostly jeweled motors at this point. Anything smaller run it at 24:1. Pre 1960 - any size, run it 24:1. If it's used for racing or high performance, double up the oil...

 

[Scaaty]

Re: Fuel/Oil

And yes, pint to 6 gallons for 50 to 1. Double for 25 to 1.

 

[Jetjohn]

Re: Fuel/Oil

Originally posted by Chief 101:<br /> Which old Johnson you talking about. In the '60's and before they were made to run a diferent mixture, 24:1 I think. Tell us what motor you have and you will get an accurate answer. Chief

The motor is a 1975 Johnson, 70HP, and thanks for the response.<br />JH

 

[Jetjohn]

Re: Fuel/Oil

Originally posted by Robby6950:<br /> And yes, pint to 6 gallons for 50 to 1. Double for 25 to 1.

The motor is a 1975 Johnson 70HP. Is the 50 to one the correct mix?

 

[Paul Moir]

Re: Fuel/Oil

Yup. Have fun!

 

[Jetjohn]

Re: Fuel/Oil

Originally posted by Robby6950:<br /> From "Chinewalker" as stated in the FAQ's section.......<br />POST-1964 JOHNSON/EVINRUDE/GALE - The official stance on 1964 and newer OMC engines is to run them 50:1 and it's a good rule of thumb to follow on the bigger motors. OMC also renegged on the late 1980s 100:1 recommendation on the smaller (4-35hp) motors, bumping them back to 50:1. I've found that the smaller (3, 4, 5, 6hp) motors from post 1964 up into the mid-1970s may appreciate a bit of extra oil as they still have some bronze sleeve bearings. I run 40:1 in my '72 4hp, as I have a pile of holed blocks, burned cranks and twisted rods that were run at 50:1.<br />1960-1964 JOHNSON/EVINRUDE/GALE - 18hp and up can run at 40:1, as they are mostly jeweled motors at this point. Anything smaller run it at 24:1. Pre 1960 - any size, run it 24:1. If it's used for racing or high performance, double up the oil...

The motor is a 1975 Johnson 70HP, its just a runabout used for fishing and pleasure boating. Is the 50 to one the best mix?

 

[Jetjohn]

Re: Fuel/Oil

Originally posted by Chief 101:<br /> Which old Johnson you talking about. In the '60's and before they were made to run a diferent mixture, 24:1 I think. Tell us what motor you have and you will get an accurate answer. Chief

1975 Johnson 70HP