Power Trim won't stop trimming up on Merc

[epundt]

My nephew has a problem with his 200hp Merc EFI 2001. The engine trims up and won't stop. He found the motor trimmed up and the relays burned out in his boat barn one morning. It happened over night. He replace the relays and it worked for about a week. It's started doing it again, the problem is intermittent. He took it the Merc repair shop, they couldn't duplicate the problem and couldn't check wiring because it's enclosed and can't be seen. He disconnects the trim/tilt when he leaves it overnight in the barn so as not to burn relays again. He just got it out of the shop, paid $147.00 for them to trouble shoot the problem, they can't find the problem, told him he's on his own. Now the power trim/tilt only works at the motor. HELP, Anyone<br />Eileene

 

[sharkcat]

Re: Power Trim won't stop trimming up on Merc

Replace the trim switch on the throttle lever ill bet its sticking on

 

[epundt]

Re: Power Trim won't stop trimming up on Merc

Could that happen after the boat is loaded, secured, put in barn and not having trimmed the motor either up on down? Another words, if you don't touch the trim/tilt switch, and if the switch is stuck, would it wait until, say, midnight, to decide to trim up? It will do it even though you haven't touched the trim switch on the throttle. It just starts doing it. Could a jar cause it if there is a short in that switch, or the switch is stuck?

 

[NathanY]

Re: Power Trim won't stop trimming up on Merc

I have seen this happen when the rubber seal fail around the buttons on the motor, and water gets in them. Try disconnecting the buttons on the side of the motor itself and see if you still have the problem.