A strange thing

[Charles]

happened en-route to Jersey coming from St.Quay Portrieux on Friday morning. The sea was seriously messed up blowing F6/7 and really quite unpleasant. Approximately 5 miles out the s/board engine’s revs went up dramatically, I turned around and to my surprise the engine was being trimmed fully up, all by itself. I quickly shut it down and continued going with the other motor. After a couple of seconds I stabbed the engine trim switch down and trimmed the engine all the way back in again, started up and continued along. It then happened again, repeatedly. As it was so rough I elected to press on with the one engine as my wife would have become very sick lolling about in those conditions whilst I investigated the problem. To my utter amazement the port engine started doing the exact same thing. As we were only about 4 miles out at this stage, I held both the trim buttons down, steered and tweaked the throttles as appropriate. This was not easy, but we still maintained 23knts and arrived home safely. Shortly after tying up in our berth I removed the TX Trim Control rocker switches and found the contacts green and corroded, causing it to short out.

Our rib has Bennett trim tabs fitted with its corresponding switches as well as the obvious engine trim switches. The question is, if I were to replace the engine trim rocker switches with say the Bennett trim switches are loads and currents something to consider? The trim tabs require far less power and current than the engine trim, or is my line of thinking not applicable.
Also, where could I acquire TX switches, Google does not really help in this instance.

[Cookee]

Charles - I would imagine that it would be the same as with mercury trim pumps - the moters will run off relays so the current that the switch is taking would be minimal.

All switches will go this way eventually unless they are kept dry (never going to happen on a boat!) or maintained properly with a silicone or similar grease.

[Charles]

Thanks Cookee - just what I wanted to hear

[Dirk Diggler]

Originally posted by Charles
, where could I acquire TX switches,

Do you mean TFX as in Teleflex?

[Charles]

No Dirk, TX switches manufactured in Gotheberg, Sweden.

[Rene]

Hi Charles

When I look up TX switches on google, all I get is a switch for a computer network.

Can you give me a bit more info and I will try to find some for you.

Rene

[dgpw]

I hear of a boat doing this. The problem was that it did it one night as the isolator had been left on. Once up it kept trimming untill the moter burnt out. Expensive so remember to isolate you engine whe leaving the boat.

[Julian]

Hi Charles

We had a similar problem on our mariner 200, kept trimming up by it self, we had to replace the solinoid to cure the problem. Was fine after that.

Julian

[Charles]

Thanks everyone, the problem has been identified and sorted out. Water ingress over the contacts made them short out thus trimming the engine(s) at will. I sourced new trim switches through Volvo Penta who now make the TX ones I was referring to earlier.

[gavin]

Charles we had similar problems with the stick mounted trim sws for our Evinrudes, instead of these we opted to fit a Carling tilt trim console mounted sw , double pole to trim both motors at the same time.For safety we introduced a switch before each pole of the double pole, therefore one motor can be trimmed up / down depending on the requirment.It also means if the Carling sticks we can switch its power supply off and not the whole boat electrics, now heres the clever bit, we also had a stuck engine trim tilt switch driving the motor down,unpluging it from the loom proved this, it was 140 euro to replace the engine switch, so I filled a hypodermic syringe with wd 40 and injected it tro the switch rubber cover and displaced the water causing it to stick and the problem never came back, Carling are reasonably priced and good quality cheers

[Charles]

Thanks Gavin - I have the switches I was after, installed them with a blob of silicone grease on the contacts and made the entire switch completely water-tight, so I hope I don't have this problem again.