Trim sending unit wires corroded

[Jez4]

The wires to my trim sending unit are corroded and broken off at the unit so my trim gauge doesn't work.
My trim control and limit switch seem to be fine and work, though. How difficult is it to replace the trim sending unit? I was told I can only buy the replacement switch as a pair with the limit switch unit. Where does the wire go through into the engine compartment? I can't seem to locate it. Help!

 

[Bt Doctur]

entry is just below the steering arm inside the boat . Most come as a kit with both units. It is the constant 12 volts in the wire that is the cause of the corrosion.
There is a mod you can do to stop it.just need to diodes from a electronics store

 

[tlewis1]

You'll have to remove the drive and even better loosen the gmb hsng. I wouldn't say it is the easiest job your first time at it. I've learned a couple tricks along the way. If your going to attempt doing it yourself make sure you've done your research and have allot of patience.

 

[wellcraft-classic210]

Just wondering -- are the wires repairable at the break ?

I had good success replacing a trim sensor with another used one by splicing the wires with greased crimp connectors and then covering with heat shrink to get through until the job could be done right -- That ended up lasting several years and still worked when I replaced the entire unit.

 

[kenny nunez]

Go ahead and and try to repair the wire first. Depending where you are may be the factor in removing the 1/4 20 bolts that mount the wires. I never had much luck removing the bolts because they were really corroded in place.

 

[tpenfield]

You buy the trim sender and limit switch as a set, but you only need to replace what is broken.

I have done the replacement without removing the outdrive or loosening the bell housing. It is a bit tricky, but do-able. 1/4" socket with long reach extension and u-joint adapter.

The wires go through the transom assembly as mentioned and each wire has a half-round grommet molded into it so that they form a full grommet once fitted together in the transom assembly. There is a plate and bolt combination that holds the grommets tight making a water tight seal.

The tricky part is accessing the bolt and threading the wires through the transom assembly