Power Trim

[SeaArk;]

My son has a Nitro with a 120hp Mercury Force. He is having a problem with the trim. When he is running an trims his motor up and lets up on the trim button the motor goes back down. The trim won't hold while running, but will move up and down while sitting still. Any advice or pointers on what to look would be appreciated.

 

[wrechin2]

Check the manual by-pass to see if it is seated. Not familiar with that engine, but should be in the same place on the side of transom bracket. If it is, then it has more than likely blown a internal seal or a check valve is stuck open. Hope this helps!