I have a 2000 Johnson 90 as seen in the picture. The boat has been sitting for a while. It was last run in March out of the water with a water hose. We engaged the prop for just a little while at low power. We saw black oil leaking out of the prop shaft where the prop meets the case as seen in the picture. We did the same thing today since we are about to put the boat up for sale and we are still seeing the leak. Does this mean I have a bad seal? If so, is this hard to replace with the service manual or should we take it in for service.<br /><br />Or, are we just seeing exhaust? The motor was idled for about 15 minutes and then we ran it for just about 5 minutes. Any ideas?<br /><br />Thanks<br /><br />