Completely darin drive. Purchase pressure gauge here or elsewhere. Pump 7 PSI and let it sit for 1 minute. Pump a total of 15 PSI and leave it for a few hours. If it is still 15PSI after 3-4 hours, means your seals are good. If you have a leak, you need to address this issue. Determine which seal is bad by spraying water on it. Most common problem is a prop shaft seal.<br />Good luck.
Oh, and gray color of drive oil indicates that water gets in oil. Metal particles could mean that your gears are worn out. You will have a few metal flakes on the magnetic drain screw, that is normal. A lot of metal particles in oil is a bad thing. <br />Water pump impeller is important. If you did not change it for 2 seasons, I would change it<br />now, rather then having it done in the middle of the season.
