Trim switch…Problem Help ! Need Advice

[Stan]

Trim switch…Problem

Re: 1989 22 Classic Merc / Bravo 1 454

The trim switch on my throttle control is not working. The down works fine but the up dosent not work at all. No sound at all. Trailer switch works fine up and down.

I thought I would just replace the trim switch…..$ 50 bucks or so ……no biggie.

My mechanic says it’s probably the sending unit. $ 100 plus 2 hours labor !

Any thoughts on what’s wrong…..the switch or the sending unit ? or ?

Thx

Stan……..

[gold-n-rod]

Sending unit isn't the proper terminology. It's the up limiter switch. It's there to prevent the operator from raising the drive too far with the trip up switch. They supposedly are a bitch to switch out. See the following write up. If you have a fresh water boat, you might consider cutting the 2 wires and soldering them back together, covered with shrink tape, but it's not advisable for salt water use.

http://www.mercstuff.com/trim_limit.htm


HTH,

another Randy

[DickB]

If there is some question about which switch is the culprit it would be worthwhile to check with a voltmeter.

[RvR]

My trim has been driving me nuts all season. It began by the solenoids either buzzing and not pulling or not working at all so I replaced them. No help none of the three control switches work. I tested the switches and they were making contact, as well as having power to them. Jumping out the tilt limit switch, which doesn’t affect the trailer switch, made no difference. I finally gave up for now, planning to check and replace all the wiring soon, and wired in a 3-position spring centered switch as a stopgap.

Easy enough to test to see if it is the limit switch by removing the cover on the starboard side unit and jumping across the two terminals. The up switch should work then if it is the limit switch. If that doesn’t work then the switch on the controller is most likely the problem.

[Greg]

I had the same trouble last year. It turned out to be the trim limiter switch on the drive. I started the replacement myself, but then ran into other problems that needed special tools so I had the Merc. mech. finish it. According to him, the only difficult area is getting the new wires thru the transom. someone told me that when you grease the drive the the trim limiter and the trim sending units should be removed so as not to fill with grease.

[blackhawk]

I'd check the trim switch in the throttle with an ohm meter and if that's okay check the limit switch. As RvR saod easy enough to check. I can't remember if it's a closed or open switch but you can bypass it. Sometimes the contacts just get corroded and need to be cleaned.

[blackhawk]

By the way, I'm betting it's the limit switch. Either it's corroded or one of the metal "ears" broke off. If it's broken I would just bypass it and save the money for gas and beer!

[rickrsbro]

look for a break in the wire as it enters the top disc of the limit cover. if you have an open connection, it's possible to trim back the wire and inch and reuse the existing wire. remove the small half moon cover and the wire seals. push the wire thru the housing while you pry up on the terminal block/brush with a small screwdriver. there is a extremly small allen key set pin that holds the wire that screws into the terminal block or brush.

make sure there is still enough slack in the wire when you get finished.

[Stan]

Ok...here’s the scoop,

The trim limit switch is just fine. It seems that the trim limit sender on the port side of the gimbal ring is the problem. The trim limit sender is attached to and covers a round steel piece that is located inside the gimbal ring.

The port side has the trim limit sender, the starboard has the trim limit switch

This steel piece that the sender is attached to, seems to be stripped and will not screw in or tighten to the gimbal ring. So when the drive rotates up, the trim limit sender along with the steel piece, rotates with the drive and does not register. The piece stripped because it was loose and vibrated a larger hole.

My mechanic wants to replace the gimbal ring i.e.: $500 plus 3 hours labor …..$ $ 750 !!

I kind of went into a mild shock ! After a little crying he said as a short-term fix he could just JB Weld the steel piece into the gimbal ring !

It seems to me that this steel piece could be secured permanently by either tack welding or ?? The gimbal ring is aluminum the piece is steel.

Ideas…..

Stan……..

I would love to find a mechanic that actually fix’s….not just remove and replace !

[blackhawk]

Stan, I am a little confused. It's been awhile since I had mine apart but the only thing I remember under the sending units was the hinge screw that bolts to the gimbal ring to the bell housing. I thought the whole unit was bolted to the gimbal ring? Do you have any pics?

[Stan]

Yes...you are correct.

The sender unit bolts to the gimbal ring. And the back of the sender unit has a many sided male fitting that fits into a steel piece in the gimbal ring. This steel piece is the part that is loose.


Stan.....

[blackhawk]

Okay, are you referring to the plastic hex piece of the sending unit that goes inside of the 12 pts of the hinge screw? If you are I think you are saying that the hinge pin is the part that isn't tightening up. So when the drive trims up or down the hinge screw stays stationary instead of moving inside the gimbal ring and in turn moving the plastic hex piece of the sending unit.

Is that correct?

[Stan]

aaaaaaaaaaaaaaa..........

Yes...thats exactly what I'm saying.

How can I get that hinge pin to tighten ? Is is loose and wont tighen. The threads stripped because it was loose and vibrated a larger hole....( so I was told ).

How long can I go without fixing this problem. It just dawned on me that, why bust my chops to fix it right now.....If I wait 2 months, I can fix it during the off season. Am I at risk of ???? damage ???

Do I need to replace the gimbal ring or can this be repaired?

thx

[gcarter]

Stan that would require a new bell housing. And this is pretty serious as all the drive torque goes through it.
Fortunately there are constantly ones for sale on eBay.
It requires removal of the drive, bell housing, all bellows, water tube to replace this part. :smash:

[RvR]

Ouch. It is easy enough to jumper out the limit switch and be able to trim the outdrive with care but that pivot pin is a bit scary.

Depending on how badly the bell housing is damaged you might be able to have it Heli-Coiled, but the unit would have to be dissembled. I’m not sure why your mechanic wants to replace the gimbal ring, unless the pivot is also worn.

With the unit down and straight ahead can you noticeably move the skeg port to starboard? If so both pivots have started to loosen. If not all of the torque is being taken up by the one good pivot pin and stressing the hell out of the pivot.

I’d be a bit nervous about a catastrophic failure, keep your TowBoat card handy. :banghead:

[blackhawk]

If the hole hasn't been ovaled out on the gimbal ring it should be fine. The threads are actually in the bell housing. As RvR stated you can helicoil it if it's not worn too bad. Did this on an alpha drive a few years ago and it worked great. Fortunately my pivot holes on my gimbal ring were okay. I helicoiled both sides because they both had loosened and had some wear. Local machine shop charged me under $100 and I did the work myself.

[gcarter]

Stan, if your 'ring is worn, this is something I did to repair mine.
http://www.donzi.net/forums/showthread.php?t=36266
You still have to remove the ring to do this but the cost is only about $150.00 in machine work. The bushings are only $6.00 each. The neat thing about this fix is they can be replaced without removing the bell housing.

[scott snider]

trim sender switch is on the port side it is for your gauge only.trim limit switch is on on starboard side it prevents you from raising your drive to high when operating your boat.the trailer switch will overide the limit switch so you can get your boat out of the water. the limit switch has no effect on your trim down circuit only your up circuit.most likely you have a bad limit switch i have replaced many.it can be done with out removal of bellhousing but is a difficult task unless you no some tricks.the hard part is fishing the wires thought the the gimbal grommet and getting the wires located back in there original position on gimbal housing(very important).you can buy a kit from merc.which has both the limit switch and trim sender for under $90.00 last time i checked .i always do both switches at the same time.i dont know what this mechanic is looking at but your sender and limit switches have no connection with each other. maybe the starboard side is the one that is stripped.maybe thats the one he is referring to? scott