1981 80 HP Mercury - Trim Issue

111torrance111

Petty Officer 1st Class
Joined
Jan 8, 2006
Messages
275
I have a 1981 80 HP Mercury, The trim isn't working & I need to lower the motor. When I tried the release knob the motor only goes down part of the way?

If I loosen either of the trim cyliders the motor lowers all the way down, what would cause this and how do I fix it.

I'm trying to make a test run with the boat to test some electrical repairs, but just can't get the trim working.

The solinoides click from the controls, but the trim motor doesn't function.

The trim system has dual solenoide and nither one works (up or down)

Thanks for any help.
 

Flossyb20

Cadet
Joined
Sep 13, 2010
Messages
24
Re: 1981 80 HP Mercury - Trim Issue

I had the same issue...first off, make sure you have a good battery running to the engine, then make sure you have a good ground and positive to both solenoids (clean them off with a wire brush). The fact that the solenoids are clicking means that the switch it good. I ended up having to replace 1 of the solenoids (I believe the front one) to make mine go down. Bolted it on and it worked like it should.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,103
Re: 1981 80 HP Mercury - Trim Issue

The manual release on that motor was never designed to allow a tilted motor to be manually let down. Opening the hydraulic lines is the only way to go. Once the motor is down, the manual release will allow you to tilt it up and down manually.

It sounds like you need to verify the motor gets voltage when the solenoids cloick. Use a voltmeter on the solenoid and ground to test for +12VDC. Alternatively you may jumper across the large terminals of the solenoid with a wire, to make sure voltage makes it to the motor. If the motor doesn't run, you may have dirt in the motor, or a bad ground. Make sure the black ground wire is clean and connected to battery -12VDC cable from the battery.

There is likely a bimetal circuit breaker inside the PTT motor. Sometimes a bit of dirt gets between the contacts, and the motor will show an open circuit.
 
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