Motor trims up while running in rough water???

2002 150hp VMAX....Recently had the tilt trim unit replaced with a rebuilt unit...It works fine, goes up/down, & holds trim in glassy water...When I hit rough water it rises up on its own and I have to keep letting it back down with the blinker trim switch...Anyone have a clue on what could cause this? Thanks for your assistance.... http://www.bassboatcentral.com/smileys/USA1.gif

Maybe TM cable hitting the switch on front panel.

I think you may be getting water around the switch on the motor. The water is allowing the up contact to be made.

My 150 Vmax will do that every once in a while, when I get a lot of backwash.