1987 Yamaha 40hp ELH 2 stroke - Oil breather query?

Betowess

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Apr 16, 2014
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I bought a refurbished '87 40hp ELH 2 stroke which has very good compression all cylinders. It runs well so far. It had lower unit damage on one side of the cavitation plate, which was welded to make it serviceable. It looks like the last owner might have backed it into a concrete barrier or something. The guy I got it from (who repaired it) found it at a marina dealership that didn't even have it listed in inventory.

Anyhow, I have noticed a persistent ring of oil below the breather in the oil tank (breather is on top of the tank) and the resulting dribble of excess oil running down the side of the oil tank. So I was looking at components online, and there is a grommet and then a "spec nylon bush" ( I guess that is a bushing ) before the breather and its cap.

I haven't tried to take my breather out yet to see if something is missing. Is there anything I should beware or be looking for. I can order the whole assembly for $28, but I am wondering if perhaps only this bushing or grommet could have been forgotten to be put back in, and if that would cause the leakage? Any feedback greatly appreciated. Thanks!
 

boscoe99

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Re: 1987 Yamaha 40hp ELH 2 stroke - Oil breather query?

Does it only leak when the motor is tilted up? Usually this can be case when oil is impinging against the parts and they don't seal like they used to. The grommet typically does not seal itself against the tank because of its lost elasticity.

There are only four parts that comprise the breather mechanism. Why not simply replace them? I see however that the cover is no longer available.

Where did you find the parts as an "assembly" and what is the part number for the assembly?

 

Betowess

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Re: 1987 Yamaha 40hp ELH 2 stroke - Oil breather query?

Thanks Boscoe99. I hadn't thought about the tilting factor, and that is probably the cause, as yesterday I used a stock tank to check the telltale and tilted up the outboard to use it. The word "assembly" was mine - I got the part listing from Boat.net... I didn't notice the cap was no longer available, so the three would cost about $22 - with the breather.

I'm not sure how to extract it all, and certainly don't want to damage that cap, but maybe I'll order the grommet and nylon spec. bushing and see if that is the problem. Thanks again! I'll report back if that solves the issue.
 
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