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Older Johnson 40HP smokes like crazy

J

Jon Dinsmore

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" 1962 Johnson, model RDS-24L,

" 1962 Johnson, model RDS-24L, 40HP 2 stroke twin. Starts easily but smokes heavily. There is also a lot of oil in the exhaust. New plugs were installed when I got the engine so I can't tell much from them. I do not recall exactly what gas/oil mix I was using but I am fairly certain it was the recommended ratio. I checked compression and got 60 psi on top but only 30 on the bottom. I am assuming the powerhead needs to be rebuilt. Or is there something else I should be looking at first? If the powerhead does need to be rebuilt could someone recommend a shop experienced with these motors. Thanks - Jon "
 
"Jon;Wake up unless you are in

"Jon;Wake up unless you are into "antiques" or dinosaurs that motor is NOT worth any kind of rebuilding --you'll spend a lot of money to get a $50.00 motor{thats $50.after you get it running} I sent you another message earlier-read it! Zeke
ps save your money and get a newer/better/more econimal engine like mid-1980's or newer
[email protected]"
 
" I'd question your compre

" I'd question your compression readings. That motor with 60/30 readings won't run - period. And it certainly won't "start easily". I am guessing that a little help from some decarboning agent (Sea Foam, OMC Engine Tuner, etc.) and a solid tune-up will get her running better. As for the smoke, it's the nature of the beast. ALL carbureted outboards are going to have some degree of smoking, with older ones likely to smoke even more. You can reduce the amount by making sure your motor is properly tuned (carb jets might be set too rich?).
- Scott "
 
oasisman------This thread is 15 years old,.-----And oil / oil mixture discussions never go away or get resolved.-----Everyone has an opinion.-----Oil / lubrication in 2 strokes is no well understood.
 
oasisman------This thread is 15 years old,.-----And oil / oil mixture discussions never go away or get resolved.-----Everyone has an opinion.-----Oil / lubrication in 2 strokes is no well understood.
You are right bro ,they are always around that why we talk about it , but using marvel mystery oil and seafoam in my Fuel has been the end of my problems, I earn my living from my Outboard
 
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