1987/88 Mercury 35hp

Started up the pontoon for the first time this year and something is rattling around in the lower unit area. Dropped it the lower unit off and found some random pieces laying in/around the shifter and the water pump. The two smaller pieces are rubber, the larger is metal, appears to be a broken washer/shim or something, roughly the size of a quarter if complete i'm guessing.


I immediately noticed gear oil was all over the water pump and surrounding areas. So I drained the lower unit and sure enough pretty much water came out with some black oil mixed in. Everything is still free/spinning.



I've never done anything else other than the impeller on an outboard. I didn't do it last year because we only took it out twice. The impeller that's still in there actually still is in decent shape (already have the kit to swap it all out). I'm guessing another seal somewhere has failed allowing the oil/water to mix.

Do I need to pull the gear casing out?

Here's a video from the initial startup, you can hear the rattle in there. I did shift into forward/reverse before shutting it down and it shifted fine.

Take the lower unit to the shop and have them pressure test it. Take the pieces with you they may be able to identify them... Dan

We can check it out for you