How is Mercruiser Alpha I Gen I Sterndrive control supposed to work?

[Cap10patNC]

If I have my Alpha I sterndrive all the way down, and I hold the UP button, it raises the outdrive until it hits the designed height for that setting, then it stops rising automatically and the pump shuts off. (Assuming my trim sensor is set to specs). Good.
If I then hold the DOWN button the outdrive lowers as far as it can go, but the pump keeps working even though it can go no lower. Is the pump supposed to sense the bottom and stop pumping?
Same question for the Trailer UP action (some variety on what this has been called over time). Should this shut off or just keep running?

 

[Westie]

That exactly how it is designed to work.

 

[Bt Doctur]

The trim up is limited by the trim limit switch and the pump shuts off once that is reached. The trailer function or the down function does not have a limit to stop the pump. You have to listen for the pump to "load up" .Try to get into the habit of hitting the up for a second after full down and a second down after full up. It releases the pressure.

 

[Cap10patNC]

Thanks guys. I was afraid of that. It always worked like that, then I wondered if that was how it is supposed to work.
I think I got a small oil leak inside one cylinder, which now won't compress all the way. Maybe some oil where it shouldn't be. Maybe forced past an internal seal.