Trim\Tilt not working, 1991 Mercury 175 XRi

[JMO1]

I have verified with a Multi-meter that I have 12.x Volts being supplied to the Trim Up Solenoid's positive post. This Solenoid has the large blue wire going out to the Trim Motor. I'm using the Trim button on the motor to simplify the troubleshooting. When I click the Trim Up button, I hear the Solenoid click, however the Trim Motor does not seem to be responding at all. I put the Multi-meter on the small blue wire coming from the Trim Switch, and when I press the Trim Up button, there is approximately 10 Volts. I also tested the post where the large blue wire going to the Trim Motor connects to the Solenoid, and it also reads approximately 10 volts when I press the Trim Up button.

Is 10 Volts enough to spin the Trim Motor?

I checked all the connections on the Trim Up solenoid, and they all seem tight and corrosion-free.

By the way, I have the Trim Down solenoid disconnected, as I wasn't able to get this Solenoid to click when pressing the Trim Down button. Also, I'm getting 10 Volts on the Trim Down solenoid post with the large green wire going to the Trim Motor, when I click the Trim UP button?? Since this is the Trim Down solenoid, I should get a reading of 0 Volts when I press the Trim Up button, correct?

The motor is trimmed about halfway up at this point, so I would need to raise it to get at the Trim Motor connections so I can troubleshoot there also.

It seems like I have multiple issue here, trying to figure out the best way to attack this.

I'm hoping the issue is with the Solenoids or Connections and not the Trim Motor\Pump\ or Hydraulics.

Please let me know your thoughts.


Thanks,
Jon

 

[The Force power]

you keep mentioning "solenoid" but do you mean relay?
use a jumper wire & apply power to the blue wire, see if it goes up? make sure you have a ground

the Trim wires control the relays up/down --- the relay allow power to flow to the motor

 

[Chris1956]

The original PTT motor on that engine should have been a 3 wire motor. A solenoid would provide power the the thick blue wire, causing the motor to trim up. Trim down is activated by power on the green wire. The black wire on the motor should always be grounded.

I would jumper the PTT motor directly to the battery to make sure it works. Jumper +12VDC to blue and battery negative to the black wire. The motor should run up. Repeat test for down.

A replacement PTT motor might be a 2 wire motor. That would require the swap out of both solenoids, in favor of relays, for it to function. Solenoids simply will not work.

 

[tblshur]

there is a manuel release screw on the side of the t&t a couple turns out will let you raise the motor by hand be careful when you loosen the screw it will let the motor fall down

 

[JMO1]

Thanks guys, I will get the motor trimmed up manually, and supply power directly to Blue, and Green connections and let you know the results.

 

[JMO1]

My 1991 XRi has Solenoids, not relays. I wasn't able to get the Trim Motor top cover off, so I couldn't do the direct from a 12 volt battery test, to make sure the Trim Motor is working. Instead I replaced both the Solenoids. I still couldn't get the Trim Motor to respond at all. The engine has now been sitting for roughly a year without being trimmed up or down, so I thought it was worth a try to tap on the Trim Motor with a hammer. I did 3 or 4 medium taps on the Trim Motor, and the Trim motor now works for both up and down.

I've had the boat out 4 or 5 times now and the Tilt\Trim has been working fine, so I'm hoping my Trim Motor is fine, just needed a few taps since it hadn't been spun in a while.

 

[Chris1956]

If you can get to the solenoid wiring, you can jumper the trim motor directly, as the solenoid heavy wire runs directly to the trim motor.

 

[JMO1]

Thanks guys.

I couldn't get the cap off the trim motor, as my motor was "stuck" in a mostly down position. Therefore, I couldn't try to jump directly to the trim motor.

I had read somewhere about tapping the trim motor with a hammer, so I tried that and was pleasantly surprised the trim motor worked at that point.

If I left the boat sit and don't trim it up and down every few days, it's locks up and I've had to use the hammer tap method 3 times this summer.

I plan to replace the trim motor this winter.

 

[Chris1956]

If she truly get stuck, you should be able to remove the 4 bolts that hold the trim body to the transom bracket. Next remove the steering cable nut and the transom bracket nut and transom mounting bolts. Slide the transom bracket sideways and the motor should be able to be lifted up to replace any part of it.

You will probably need to remove the transom bracket to replace the PTT motor anyway. Inspect the stainless steel pin on the bottom of the PTT unit for leaks. If it leaks at the center tilt cylinder., the PTT casting could be bad, and you may need to replace the entire PTT unit.

A new PTT motor may be the two wire variety, but should come with relays and a wiring harness. It will replace your old motor and solenoids perfectly.