Power trim will lower but not raise

[blur]

I have a '74 mercruiser sterndrive. The trim pump works fine when I'm lowering the motor, but when I try to raise it nothing happens. The pump motor doesn't make any noise. The trim controls are sending voltage, but I do not know how to troubleshoot the system itself. I'm hoping that the trim sensor is showing that it's at full raise and keeping the pump from running. Can anyone tell me where the sensor is, hot to test it or how to bypass it? Failing that, can anyone advise how to test the pump motor itself? <br />Thanks for any help.

 

[Bobby Powell]

Re: Power trim will lower but not raise

Hi Blur-<br /><br />I have a 84 merc. outboard that had the same problem. It turned out to me the "up selienoid". it only cost $17 for the part from the merc dealer.<br /><br />the way I tested it was by switching the motor input leads from the selienoids. If the problem becomes that the motor will not tilt down but the motor will tilt up then whola! there is you culprit.<br /><br />I am not sure if you trim motor setup is similar to mine, but I am sure that someone will be able to guide you the right way.<br /><br />you can look at it this way... if you cant raise the outdrive that means more time in the water.

<br /><br />Good luck-<br /><br />Bobby