My first outdrive

[Mawi]

I recently bought a Tahoe Q5i with a 4.3 MPI engine and Alpha One Gen 2 outdrive, my first outdrive ever. After fast runs, it trims itself fully up, then refuses to go down. The pump runs, but movement's erratic, coming from sailing, this quirky tilt/trim system is a whole new challenge.

 

[anchorandgo]

After you run your engine at high RPMs, auto trim-up might happen because of overheating safeguards. So, first off, check your fluid levels and bleed any air out of the system. Try giving those pump connections a good look too. If you notice things are moving funny, it could mean there's air stuck in the hydraulic lines

 

[coffeestrangers5]

Have you checked the wiring at the trim pump, especially the blue and green wires? Sometimes they get loose or corroded and cause weird behavior. Also, did the trim gauge show anything unusual when it acted up? That might help narrow it down.