The Boating Demons trimming my Motor!!

[Aquaman-PSD]

Alright so this past weekend I took my boat to a lake about 3 hours from my house. Other than a self-caused battery issue the boat ran great! however during the night it rain... a lot! then it rained the whole way home. Needless to say everything was soaked! when we got home and parked the boat we were getting all of our equipment out and all of a sudden my motor started trimming up! there was no one near any of the three trim controls. I was so confused that it got to the highest point and continued to run. I bumped it in trim down and it stopped I put the motor back on the transom saver and waited about ten minutes and it didn't do it again so I went inside to finish up a few things. When I came back out an hour later the motor was trimmed all the way up and the trim motor was just clicking.... I couldn't get the motor to move at all. So i towed it to where i store it and when i got there I was able to get it down again but i could still hear the trim motor clicking and humming. I disconnected the battery terminal to stop any further damage. Long story short I talked to a guy with a similar motor and this happened to him before. He said it was a trim relay switch the was shorted out. I'm afraid that this switch has now burn up my trim motor. Does anyone know if these trim motors burn up easily or do you think if i just change out the relay switch will it be OK? The motor is a 86' Johnson GT200. It only has 170 hours on it so I am really hoping that the trim motor isn't toast! Sorry for the long post but I am supposed to take the boat back to that same lake this weekend and need to get this problem resolved!

 

[archcycle]

Re: The Boating Demons trimming my Motor!!

Disambiguation: relay switch - a relay is a circuit that takes a tiny current such as from the thumbswitch on your controls or on the side of the motor or transom or wherever and uses it to activate turn on a flow to a high current device like your trim system's hydraulic pump; it is an electrically operated switch that switches on when it gets a current from a manually operated switch sort of like an electrically activated floodgate. Trim switch - this is one of the manual push button operated switches that sends the tiny current to the relay which switches on the big current and then your trim motor starts doing things at your command.

You have one of two problems (four if you count each set of controls as one..). Very likely one of your 3 trim switches is shorting and sending current to the UP relay. Less likely your up relay is shorting out and allowing the high current without being activated by the low current side.

Since it keeps trying to go up you could swap the up and down relays and see if it tries to go down on its own, or you could just buy a new $20 relay and swap the up relay. If it doesn't solve your problem at least you know that the up relay was good and now you have an important and valuable spare. If your problem isn't solved then it's a switch shorting out. Expose all of your trim switch wiring. When it starts trying to run on its own then disconnect one switch after another until it stops trying to run and you've got your bad switch. Decide whether it's due to poor wiring or a bad switch and do something about it.

I intentionally avoided the multimeter because it's not like you need to find out if or how much current is flowing. We already know that current is flowing and how much is probably irrelevant considering that any is too much. Alternatively to the above you could pull the relay and then stick the multimeter probes into the relay's socket and wait to see if the relay's activation lines (from the switches) are getting current but then you'd still have to go switch to switch to find out which one was sending it.

 

[metriccrescentwrench]

Re: The Boating Demons trimming my Motor!!

This could be caused by a trim relay, but I'd think it's more likely because of water in one of the trim switches. You'll have to do a little detective work to figure out which one by disconnecting all three switches and then reconnecting one at a time to see if the problem appears. If the problem persists with all three switches disconnected then it's a stuck relay.

Also, if by chance the trim motor got damaged you can find an exact replacement for it on ebay for around $75 as I recall. It's not super difficult to replace, but the entire trim unit has to come out to do it.

 

[archcycle]

Re: The Boating Demons trimming my Motor!!

And as for burning out the trim motor - it's possible it burned out but it's also possible it was just overheated. If it's burned out then you just need a new motor which is the cylindrical part that the wires go to which is screwed down onto the pump it operates. Rebuilt motors are cheap and highly available. You may have a hell of a time getting the trim system off to replace the motor if it is dead, but it's not complicated it's just difficult. A search on this forum will turn up lots of threads about replacing the motor.

 

[Aquaman-PSD]

Re: The Boating Demons trimming my Motor!!

When it first happened I figured it was a shorted switch. If I wait until its dry and then reconnect the battery terminals and it doesn't trim up then I should be pretty sure that its a switch right? Will I be able to see any visible signs of arcing or anything on the bad switch or relay? I am not very good will electrical problems but I know three people that have the same motor or something a lot like it so I should be able to figure it out. BUT will i have to pull the motor off to replace the trim motor or just brace it in the up position? The motor weights over 300 pounds I beleive so pulling it would be a real Pain in the outdrive if you no what i mean!

 

[archcycle]

Re: The Boating Demons trimming my Motor!!

Not all wet switches malfunction and not all malfunctioning switches are wet so don't bank on that being what's wrong. Likely the only tactile indication of the malfunction will be the trim motor doing something it's not supposed to. You really don't have to know anything about electrical systems other than don't arc wires and take pictures or take notes before unhooking things and then hook them back up the way you found them to troubleshoot this one. Just expose the switch wirings, hook up the battery, wait for it to start running on its own and then disconnect switches one at a time until it stops running. If you do end up needing to replace the motor then you do not have to remove the outboard you just prop up the motor, remove the giant tilt pin (ha, just remove it, sure ) which threads through the motor and tilt arm coming out of the TnT unit, unbolt the bolts around the sides of the unit, and drop the entire TnT unit out of the midsection.

 

[Aquaman-PSD]

Re: The Boating Demons trimming my Motor!!

Good news! I bought a new relay switch yesterday ($23.99) and went to put it in the motor late last night. When i connected the battery cable, with the on board charger hooked up the trim purred like a kittin! sounded fine and I sat there for a good 15 minutes and nothing happened. I didn't switch out the relay because I didn't have the neccesary tools to take the cover off. So I disconnected the battery cable again just to make sure it didn't happen again. I am going to replace the relay tonight and take it for a spin. If nothing happens I will just try to keep the old gal dry for a while and if it happens again I'll start checking switching.