On these motors the spring-clutch in the drive shaft needs paying attention to. These can move apart and put a lot pressure where it doesn’t belong. And, as people are saying here, changing the water pump impeller is a project because the power head has to come off (because there is no other provision for disconnecting the shift rod). while it’s apart you probably want to pay attention to the lower crank seal. Nice motors when serviced properly.
As for manuals, the official ones can often be found on ebay for reasonable prices. Wish I’d learned that earlier.
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