Mercury 90hp tilt/trim problem query

[JayDee]

Hi, <br />I have a mercury 90hp 3cyl 2 stroke 1988 outboard. I cannot get the tilt/trim to operate. There is a clicking noise when I operate the up/down control but no motor noise. The battery is fully charged. before the trim stopped working I noticed that it was slow on startup then once it got going it worked fine. I thought it may be just a battery prob. Now battery is charged and trim has stopped working totally. Any Ideas where I should look? If there is no quick fix is there a way to tilt the motor up manually so that I can trailer it to a mechanic?<br />Hope you gurus out there can help. SOrry bout the full on essay I have just written.

 

[michaelbr1]

Re: Mercury 90hp tilt/trim problem query

There should be a bleed screw somewhere on the unit. Mine are plastic and on the starboard side of the trim/tilt assy, and I have to stick a screwdriver through a hole in the engine mounting bracket to get at it. If you open this screw, you should be able to pull the motor up by hand.<br /><br />I just had to replace one of my trim motors at $200 for the unit. My problem was that the outside housing rusted through allowing water to get inside. <br /><br />I had to repair the other trim motor a couple of years ago because the wires had become exposed due to the insulation cracking and corrosion setting in. The symptoms in this case were the same as yours (except I heard no grinding noise). The motor just wouldn't work properly - sometimes in one direction, sometimes in the other until finally, it quit working at all.<br /><br />I removed the trim motor, took it apart, and cleaned inside. I replaced the wires with a heavier gauge wire from an old extension cord I had and reinstalled it. <br /><br />It's worked ever since without a single problem.<br /><br />Good luck...

 

[WillyBWright]

Re: Mercury 90hp tilt/trim problem query

EASY way to tilt it manually? What Michael said about the plastic relief valve. But you'll need a strong back or some assistance. They move slow and they're heavy.<br /><br />Sounds like the brush holders in the trim motor rusted up. That'd mean there's water in there.

 

[JayDee]

Re: Mercury 90hp tilt/trim problem query

Thanks for you info guys. If after I have tested the electronics and it appears to be a defective motor, what is the procedure to remove the pump motor. One mechanic telling me that I would have to remove the whole outboard from the boat in order to remove and replace the pump motor. He also stated that it would cost approx $1500 AUD for the repair which is probably nearly the cost of buying a whole motor 2nd hand. Looking at the pump motor it looks fine no sign of corrosion so I am thinking that the motor may just need new brushes or has an open circuit in the wiring. It is a 3wire square type. Has anybody removed one of these? It is on a 90hp late 80's 3cyl Mercury, an OB*** serial No. i believe. Any info would be great.<br /><br />Cheers <br /><br />Jon

 

[michaelbr1]

Re: Mercury 90hp tilt/trim problem query

I posted this response on another boating forum that I follow. Same topic. Not sure if your motor is like mine, but they shouldn't be too different.<br /><br /><br />

I just had to change one of mine last month (Merc 175). <br />There are only two bolts that hold on the trim/tilt motor. You can see the one closest to you; however, the other is between the motor and the transom. The hydrolic trim/tilt assy is bolted to the mounting bracket with three bolts on each side. Those had to be removed, so I could get the assy far enough away from the transom (about an inch) to get a long allen driver (like a screwdriver only with an allen tip) between the motor and transom to remove the bolt (requires patiance). <br /><br />I ordered a remanufactured lift motor from go2marine.com. You have to match the motor with the type that goes to your engine and compare yours with the pictures in terms of shape and number of wires going to it. It's pretty descriptive.<br /><br />Mine cost just under $200 with shipping (no tax) and took about 7 days to get here.<br /><br />The link for the Mercury/Mariner lift motors is...<br /><br /> http://www.go2marine.com/g2m/a...3875/ <br /><br />Good luck.

 

[emckelvy]

Re: Mercury 90hp tilt/trim problem query

Before condemning the tilt motor and $$$ for replacement, have you checked the solenoids? I had a 115 Merc I worked on last year that had total failure of both the up and down trim solenoids. Very common to see these or the starter solenoid go bad.<br /><br />The solenoids would click, but pass no power to the trim motor. I was able to to a 'quick & dirty' diagnosis by jumping across the solenoid. Make sure there's no gas fumes around if you do this!<br /><br />Just a thought, solenoids are a lot cheaper to replace than tilt motors..............ed

 

[JayDee]

Re: Mercury 90hp tilt/trim problem query

Thanks so much for your info guys. It did end up being the motor after doing some diagnosis with a multimeter. Just like Michaelbr described, I pulled the trim system apart without pulling it all the way off the outboard. Turned out the motor brushes were worn and siezed in their housing. bit of a clean and lube, put it back together and is good as new again. <br />Cheers u have been a great help.

 

[dtmayfield]

Re: Mercury 90hp tilt/trim problem query

JayDee
My 1989 Mec 75 HP is doing the exact same thing as yours was. How hard is it to do? Do you remember the cost of your parts by chance?

Thank you and any info would be much appreciated.

Darryl
dtmayfield@gmail.com

 

[pobo]

Re: Mercury 90hp tilt/trim problem query

Before condemning the tilt motor and $$$ for replacement, have you checked the solenoids? I had a 115 Merc I worked on last year that had total failure of both the up and down trim solenoids. Very common to see these or the starter solenoid go bad.<br /><br />The solenoids would click, but pass no power to the trim motor. I was able to to a 'quick & dirty' diagnosis by jumping across the solenoid. Make sure there's no gas fumes around if you do this!<br /><br />Just a thought, solenoids are a lot cheaper to replace than tilt motors..............ed

sounds like I might have the same problem but also my motor doesent start and same clicking sound. would it be the same solinoid.