Trim indicator help please.

[KazooTom]

I have a 1989 sea ray 180BR. 4.3 liter Mercury alpha 1 out drive. I am trying to understand and repair the trim indicator on the dash. This boat has a trim control on the left side of the throttle control and on the right side is just lowering and raising the out drive. No trailer button. My problem is the trim indactor on the dash does work. I am alway going up and down with the trim when using the boat not knowing where the drive is up or down. I tried to adjust the sensor on the right side of the stern drive standing behind with no sucess. I took the sensor apart and found rust stains from water. Cleaned it up and now when I move the sensor the needle on the guage moves then stops then jumps with no smooth action. So here are my questions.
1. There is a sensor on the left side that looks old and has bare wires. Does this have any pupose?
2. If I replace the right side will this solve my trim indicator problem?
3. How hard is it to replace the sensor the wires disappear in to the stern drive?

Your help would be great.
Thanks Tom

 

[TheHunter990]

Re: Trim indicator help please.

The left side sensor is for limiting your max trim up, to go higher than that point you need to use the trailer mode. You should replace the wiring/sensor if it is bad.
Sounds like you do need a new right sensor as well since cleaning it didn't work help. It seems the wiring is ok as the needle does jump around.
I'm quite sure you need to take the drive off to change sensors. Wires go inside the boat inside the gimbal housing.

 

[stonyloam]

Re: Trim indicator help please.

1: The "sensor" on the PORT (left) side is your trim limit switch. If it has bare wires showing, chances are it will fail soon and your trim switch will no longer work. Try some liquid tape to protect the exposed wires.
2: That is the trim indicator sensor, so maybe.
3: It is a MAJOR PITA.

 

[tpenfield]

Re: Trim indicator help please.

1. There is a sensor on the left side that looks old and has bare wires. Does this have any purpose?
2. If I replace the right side will this solve my trim indicator problem?
3. How hard is it to replace the sensor the wires disappear in to the stern drive?

Your help would be great.
Thanks Tom

As stated the 'limit' switch is on the port side and prevents you from trimming up the outdrive too much while under power. You then have to use the "trailer" button at the helm to move the outdrive any further up (that is typically called the "tilt" range, as opposed to "trim")

It sounds like your trim sensor (starboard/right) side) is due for a replacement . . . probably the resistive material has worn off on the internal part of the sensor. The service manual will tell you to disassemble a bunch of stuff in order to replace the sensor. However, I have done it without taking things apart. the access is pretty tricky, as the wires feed through the upper part of the transom assembly. The wires have mating grommets that keep things water tight. There is a fastener and a retaining plate that hold the grommets in place. Removing and re-fastening the fastener and retaining plate are the tricky part.