2016 Yamaha F300 gear oil smell when running

[fisherman73]

I have a new to me F300 with around 575 hours on it. I had ran it once or twice immediately after buying it and it all seemed good. When doing some annual maintenance, it seemed like the lower unit oil level was low, although I didn't measure what came out, it did not look at all like the approximately 2 qts that it took to fill it but the fluid looked and smelled normal. After doing the service on my next trip I noticed a very pronounced gear oil smell when running, also a small amount of sheen on the water around the motor at the dock. I see nothing whatsoever dripping but it does seem to be a bit low after a few hours of running. At least there is no oil dripping out of the hole like it was when I plugged it. It's very difficult to get anything in the check hole to dip it. My question is can the input shaft seal be leaking and pushing oil up into the cooling system only when running? No milky fluid at all but terrible gear oil smell that made everyone not feel good when running.

 

[boscoe99]

I have a new to me F300 with around 575 hours on it. I had ran it once or twice immediately after buying it and it all seemed good. When doing some annual maintenance, it seemed like the lower unit oil level was low, although I didn't measure what came out, it did not look at all like the approximately 2 qts that it took to fill it but the fluid looked and smelled normal. After doing the service on my next trip I noticed a very pronounced gear oil smell when running, also a small amount of sheen on the water around the motor at the dock. I see nothing whatsoever dripping but it does seem to be a bit low after a few hours of running. At least there is no oil dripping out of the hole like it was when I plugged it. It's very difficult to get anything in the check hole to dip it. My question is can the input shaft seal be leaking and pushing oil up into the cooling system only when running? No milky fluid at all but terrible gear oil smell that made everyone not feel good when running.

I am not understanding 2 quarts of oil being required.

 

[99yam40]

I am not understanding 2 quarts of oil being required.

you have to wonder where he put those 2 quarts into.

people do strange things sometimes

 

[fisherman73]

I did both my main and kicker at the same time, and was thinking that I was substantially into my second quart when I got it to come out the check hole. Possibly I just had it over full. Checked it again this morning after it sat vertical overnight and did get a trickle. I'll run it again and see if the smell has disappeared.