Motor trim/tilt - possible short?

[Zebco33]

My 1999 Johnson 200hp VRO started to automatically trim down when I started her up . I was able to counter the trim by switching to opposite trim (UP) -- it stopped the motion and mad her trim up. This has happended on several occasions. I can hear the actual motor come on, so I knopw she is not just slipping down b/c of a hydraulic leak.

Anyone have any ideas> Areas I'm going to look at are on the throttle trim switch and the OB motor trim switch.

She's my first bote, so I'm sure I have alot to learn.
all comments, lessons learned and help appreciated. thank you. Zebco33

GW 226

 

[SlimJim]

sounds like a bad switch.

 

[plymouthgrady]

trim motor

try spraying some CRC or WD-40 into the trim button on the throttle and also check the relays under the engine cover. (hit the trim button and listen for the clicking). Pop them out- they are male/female- check for corrosion, spray and put back.

 

[BobP]

Water may have entered your T&T switch.

Also pull off the cover on your T&T relay box on the engine, how does it look, any white stuff get in there (salt from water)? Check all connections and the sockets of the relay. These boxes are not waterproof, and water can get in there. Salt is not an insulator.

On my dual binnacle controls from the orginal Johnnies, one of the wires that ran from the switch down the handle was cut by a non-finished edge of the casting at the opening of the handle base where it turned 90 deg.

You may also have a nicked or partially cut harness cable somewhere in the pass from stern to bridge, not likely, but if all else fails to solve it ...

If you can get your hands on a 500V megger, it wil be easy to verify good wiring vs. grounded wiring or circuits.

 

[Grog]

I don't really know Johnsons but if the trim only runs when it's turned on and works normally with the key off it sounds like a short.

Meggers will give you a nasty shock and may be bad for the boat's and engine's electronics.

 

[BobP]

Grog, since the megger tests insulation, so if the harness cable runnning through the boat is in question, you disconnect all wires from both ends, then take one wire and connect all the others together and megger between the one and all the others, then continue to the next. Weak insulation will be found.

Wouldn't use for anything else, perhaps a switch or two.

The member didn't say it always acts up, sometimes.

I had a toggle switch on the console top of my 20 ft Mako, the same thing happended in my driveway. I noticed the engine tilting up by itself. Didn't react in time, the lower unit lifted and went through the garage door !

Water passed the rubber boot on the toggle and shorted it intermittantly. A megger would have picked that up.