Trim Gauge

[sogood]

Hello all and greetings from Ireland. I have been a regular visitor and lurker, but have joined up now, as this seems to be a very active and vibrant community. Anyway, long story short, I'm tidying up a Wellcraft 250 Sportsman, with a 5.7 liter Mercruiser inboard and an Alpha 1 outdrive. sorting out some cosmetic repairs and some electrical issues. One thing that has me scratching my head is the trim gauge.

All the old original gauges were replaced by a previous owner, with Faria gauges and the trim gauge is reading "UP" when the power is off, or power on with the ignition off. Then when I switch on the ignition to position 1, the gauge shoots immediately to "DOWN" and all of this happens regardless of whether the leg is up or down.

​The gauge is connected up properly, as per wiring diagrams and rotating the trim signal sender on the outdrive has no impact at all.

So, a faulty sender, a bad connection somewhere or any thoughts? I was thinking of disconnecting the sender at the transom and bridging the cables to see if that has any effect. Any thoughts much appreciated.

PS. I was going to post this on the Wellcraft forum, but replies to posts are as scarce as hens teeth over there!

Thanks in advance.

 

[Scott Danforth]

welcome aboard.

you posted in the correct location

I would start by disconnecting the gauge and reading the voltage going to the gauge on the two power supply (+ batt and ground). make sure they are correct. the gauge should be labeled I (ignition), S (Sensor) and G (Ground). there will also be a lamp connection

the trim gauge is simply a variable resistance to ground (like a fuel gauge). you can read the resistance using the ohm meter of your gauge sender wire to determine if the sender is working.

 

[sogood]

Thanks for that. I already looked at the connections and they are all clean and good, but will check as you suggest. I have a few minor electrical gremlins and this may or may not be related.

​Thanks again.