I've been having a hell of a time trying to stop both trim tab and drive pump from leaking between the reservoir and the pump/motor. I have pulled all three off twice and changed the o-rings. The reservoirs look good as far as I can tell. These are on a 27' Fountain and I was thinking that I was just over filling them but they will leak oil out of them even after the oil level is below the minimum mark on the reservoir. Any suggestions ?

Are the pumps mounted to the transom?

The tab pumps on my previous boat leaked all the time. I put a wedge shaped block of wood between the transom and the pump to compensate for the angle of the transom.

Worked great, no more leaks. I'm thinking about doing this again because i have the same problem with my current boat.

Yes, they are mounted on the transom. I do have a Fountain so you know that they are tilted back a lot when the boat is sitting in the water.

Highball, I have the same problem. Did you find a resolution?