1982 90hp Johnson wet plugs,exhaust etc

[alanR1]

I brought back to life this motor after being frozen for 2 years. The compression is good all the way around with no scoring. I have been running it on the muffs only because I am putting in a new floor. I run it for about 10-15 minutes on the muffs once a week. I have been running the oil heavy since it was somewhat re-built. Which gets me to my question, the plugs are wet and a little yucky and the prop where the exhaust comes out is greasy and nasty colored. I imagine it is just burnning off the junk inside the motor and is extra greasy because of the extra oil in the gas. Should after running on the water when I get it in the water, I run a tank or two of heavy gas through and then do a de-carb and then run it with the normal 40:1 mixture. How does all of this sound? Any suggestions are welcome.

 

[angus63]

Re: 1982 90hp Johnson wet plugs,exhaust etc

If it is "rebuilt", you should run 25:1 for 10hrs,varying rpms and not exceeding 4k rpm. I believe that motor is a 50:1 motor after breakin.

 

[alanR1]

Re: 1982 90hp Johnson wet plugs,exhaust etc

I am running it at 25:1 and I plan on running it at 40-50:1 after about two tanks worth. Does running it at 25:1 make the plugs really wet and make all of that carbon and oil run down the foot and out of the prop? Will the decarb after break-in clean most of this crud up? Thanks for suggestions.

 

[angus63]

Re: 1982 90hp Johnson wet plugs,exhaust etc

Plugs will get a bit oily. Unburnt oil will be noticeable from the exhaust (especially at idle). I would run for a few tank fulls at 25:1 before decarb to burn up excess oil (not carbon). After rebuild, you should not have to decarb for at least 100 hrs if you use decent oil at 25:1.