Trim Tilt sender unit repair.

[Gon Fishun]

2 years ago I replaced the seized trim tilt sender unit on my Evinrude with one from fleabay at a good price. Well about 3 months back I was having trouble again with the relay's and wiring in the junction box for the tilt, bad connections corrosion etc. I replaced the fuse and the connectors and everything was sweet until I tilted the motor and the trim gauge didn't work.
Now electrics is not one of my forte's, so trace all the wiring front to back, check the gauge etc, anyway weeks later I found the sender unit wasn't working. This is after checking with an ohm meter whilst reading the workshop manual and trying to learn Ohm ?????
Just coincidence the sender packed it in at the same time.
Back onto fleabay to track down another sender, the best I could find was about $150 in America and $60 delivery or second hand. Used was out of the question. Any hoozle looking at the back of the sender, clear rubbery resin stuff hiding what looked like a potentiometer or a pot, you know, those volume control swizel thingys, as the elctrisical guys call em. What have I got to loose, cut it out with a Stanley knife, push it out and bingo, its a pot. Gave the boys at the Auto shop in Woodford a ring , who also are stockists for Jaycar, and they carry them on the shelf.
Down to the shop and ah shit, they have a 1K-10K- 500K-1000K. WTF . OK , means jack to me. Executive decision, we will have 1 @ 1K and 1@ 1000K @ $2.85 each, gotta be 1 or the other. Got the Ohm meter out again to work out which one. Put the Ohm meter away. Connected each and tested, way to go, one worked. Little bit of trimming, reseal the newey back in and Bob's your Uncle. It works better than the original.

[Fed]

For future reference supposed to be 88 Ohms so the calibration could be off or twitchy only using 88 out of 1000, lucky to get enough manual movement adjustment.
See the ** reference to swapping Yamaha to Mercury in the resistance picture, full trim is full gauge so tilt is off the scale.
Cheap enough fix to see the needle move though.

OMC work in reverse to Mercury so if you ever need a new after market gauge make sure you get the right one otherwise up will be down & down will be up and it can't be corrected by swapping wires around.

[Gon Fishun]

For future reference supposed to be 88 Ohms so the calibration could be off or twitchy only using 88 out of 1000, lucky to get enough manual movement adjustment.
See the ** reference to swapping Yamaha to Mercury in the resistance picture, full trim is full gauge so tilt is off the scale.
Cheap enough fix to see the needle move though.

OMC work in reverse to Mercury so if you ever need a new after market gauge make sure you get the right one otherwise up will be down & down will be up and it can't be corrected by swapping wires around.

Thank's for the info Fed.
I had a look at the pot I didn't use and it had A100k on it, so the one that I did use had A1K?? . I managed to adjust the sender so when the motor ( tilting down) got to the second stage on the trim, the gauge started to move. It has a scale between the up and down marks which the needle works in now. It's all good.
Cheers.
PS I will copy and paste that info to file for later use.