At the top of this page, click on ‘Resources’, then Links, then scroll down to ‘For the Old Outboard’, then Art Dekalb’s website; then on his website click on his ‘5 point plan’. Great plan of action for any old outboard!
OK, well the factory said these engines can be run on 50:1, which is one pint of TCW3 outboard oil mixed with 6 gallons of regular fuel. Consider mixing a little heavier to preserve the plain connecting rod bearings.
This is a unique engine, only made for one year. The 69 and later models were 4hp, and there are several subtle powerhead differences. although the “owner’s manual” from 68-72 3-4hp Evinrude or Johnson models should be just fine. Have you looked on ebay?
If you want a service manual, or parts manual, I would stick with the 1968 books for the reasons mentioned. But either an 1968 Evinrude or Johnson parts/service manual should work just fine for you. Again, look on ebay.
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