Boating How-To’s - F250 trim activates on its own ..

Splash the boat yesterday--my marina does this. Take it for fuel and shake out run to get ready for fish trip first thing tomorrow am, get back to the dock and one engine trims its self down after I trim the engines out of the water. Tried to figure it out to no avail. Every time I trimed it up it would go off in spurts putting it back into the water. Sometimes it would stay on when trim all the way down; if I hit the switch at the throttle it would stop trimming down while I was doing that. If I activated the trim switch on the side of the engine it would stop doing it as long as I held the switch on in the up mode. I just had work done to stop the engine bracket corrosion and they worked on removing the corrosion from the trim piston housing so it is more than a coincidence ? that I am having an electrical issue with the trim? I don't know that for sure yet but the trim keeps switching itself on.

Any one see this before and have any suggestions.....I am about to drop the fish trip tomorrow because I dont want to burn out the motor or the battery. If I could stop it from running I would go and deal with no trim for that engine. Any help is greatly appreciated. Bought two new batteries this spring and the marina put them in. The other engine is fine.

I had a similar problem some years ago. One of the switches at the binnacle was corroded and would intermittently activate.

I looked at that and sprayed them with corrision block and didnt seem to affect it at all. I assume you put in a new switch?

Yes, put in new switch. it was shorting and the only way to stop it was to disconnect from power.

Not trying to hijack your thread but my 1996 Johnson 60hp did the same thing yesterday. Unplugged the trim switch on the engine and it still did the same thing. Changed out the relays on the side of the engine. If any one has a good idea or opinion I'd really appeeciate your advice.

I disconnected the switch on the binnacle this am. Inspected it closely and could see that the switch was shot by feel. When pushing down on it, it was mushy feeling. Clipped it and the problem stopped and was able to use the trim with the switch on the lever...moves both at the same time but who cares. Had a great day fishing...slammed fish... great weather and seas, and I almost cancelled due to this issue. Thanks mike.