Trim gage intermittent

[Wxguru]

When I picked up this boat in June, the trim gage was reading on the boat when run on the muffs in the driveway. It still reads just fine when on the muffs in the driveway.

Both times we have launched the boat...the first 5 or 6 seconds, the gage reads just fine....then defaults to the fill down position, with no input by me on the trim switch.
The entire day on the water, the trim gage indicates in the down position with no movement....maybe a flutter here or there when given trim input at the throttle handle...but otherwise nothing.
Next day in the dirveway....back to working.

Anyone run into this issue?
Is this possibly an issue with water getting to the wiring of the trim position switch on the housing and shorting it out temporarily?

 

[tpenfield]

Sounds like the wiring is exposed and the water sort 'shorting' it out.

 

[Chris1956]

MerCruiser Alpha trim gauges are exposed to water. They are solid copper, but even that is affected by corrosion to some extent. You can repair it, or better yet, ignore it and trim by sound and feel.

When the motor is all the way down, the pump will sound different. When the boat is trimmed for cruise, the steering will be light. The steering should pull left at max trim