1962 Johnson 40 hp electromatic fuel mix

[gary cooper jr]

I am currently trying to revive this oldie but a goodie, am I correct in using a 50:1 fuel oil mix??

 

[gary cooper jr]

I picked up 2 1962 Rude Lark IV Electric shifts, for additional parts for $160.00.

 

[racerone]

Mix ratios for those will always get a bunch of opinions !------Originally it was 24 :1 for that motor.----Service bulletin may have included it to run at 50:1 like 1964 model of your motor.------If you look up parts books on the 2 models you may find that parts are all the same.------Other opinions will no doubt follow here.

 

[Scott Danforth]

I thought the mid 60's were 32:1.

 

[racerone]

???-----No the MARKETING people decided that 50:1 mix would sell more motors to a public that knows little about lubrication.----OMC never had 32:1 mix in the 1960's

 

[F_R]

Mix ratios for those will always get a bunch of opinions !------Originally it was 24 :1 for that motor.----Service bulletin may have included it to run at 50:1 like 1964 model of your motor.------If you look up parts books on the 2 models you may find that parts are all the same.------Other opinions will no doubt follow here.

I'm in agreement. But if I tell you to run 50:1 and it blows up, you will be mad at me. Maybe even sue me if you can find me. Never mind that it was going to blow up anyway.

 

[jimmbo]

I'm in the 50:1 group. But as F_R said, if the engine blows up, for whatever reason, you will be blaming the advice. I have seen the Service Bulletin. OMC had a greatly reduced number of Warranty Claims from engine damaged by Pre-ignition after the 50:1 was introduced. Less carbon forming in the heads, Remember though this was prior to TCW oils. The service bulletin advising 50:1 for pre 64 engines was in the late 60s or very early 70s and required using Evinrude, Johnson, or OMC oils, though I think Mercury or Chrysler oils would have be acceptable too

 

[boobie]

I was always told that if all the bearings in the motor were needle bearings, use 50:1. Any bushing type bearings, use 24:1

 

[racerone]

There are lots of the 6 hp models 1965 to 1979 running just SUPER on 50:1 .----Big end bearings are needles and the rest bushings.-------Well sized / designed bushing too.

 

[jimmbo]

Our 1964 5 1/2 had a bushing for the lower crank. Even at 50:1 there was plenty of residual oil to keep it well oiled. I know a lot of pre 1954 engines with bushings required 16:1 ratio

 

[gary cooper jr]

Thanks for the help!