Bottom End Seal change - Outboard Noobie

Hey all,

Noobie when it comes to outboard repairs, but Ive been rebuilding snowmachine and atv engines so i know my way around fairly well.

Just purchased an 81 Johnson 20hp, and took it home and bottom end oil is milky as can be. Thinking I should do a seal kit, since its winter anyways! Thought about just getting new drain bolt o-rings and trying that, but im not sure how often those are the cause of a leak. Its hard to know if the seals are truly bad or if it has just not been drained in the recent past.

Looking like 60-70$ for an OEM gasket set locally, would this be easy for me to do at home? Do i need any special pullers or tools?

Thanks!! Love this forum already.

No " special " tools or skills required.

Pressure and vacuum check it before taking it apart. That way you won't miss anything. Do it again when you're done with it.

Thanks guys! Im assuming the dealer would need to do the pressure/vacuum check as thats certainly going to require some special hardware? Is it worth paying the dealer to do this job, if it means they can pressure test it to insure its proper? Or is it pretty safe to assume if I take my time, i can reassemble leak free? Just wont be aware of any cracks or other leak points without a pressure test.

One point of concern I have is Ive got no service manual and no torque specs for reassembly.

I wouldn't work on a motor with out a service manual. JMO>

It could very well be just the type of gear oil was water in the bottom of the gearbox? Put new nylon gasket on the drain/fill plugs and top it off and see if you get water intrusion after running it hard for a bit. Boatinfo library has manuals you can look at if you dont know how old the impeller is just put one in along with new spark plugs.

The motor was ran in a barrel for me when i went to buy it, I took it home and about two hours later I had drained the oil and it looked like this, uniform throughout. No chunks or shavings which is good. Ive only ever used clear brownish gear oil so i dont know of any other types that could lead to this colour. When i drained it, there was no distinct variations in the flow (water vs oil), but that is likely because it was just run a few hours prior I would assume?

Thank you guys!