OMC 1.6 L Sea Drive Trim / Tilt Runs By Itself

rkirkwo1

Cadet
Joined
Mar 31, 2006
Messages
9
I have somewhat of a scary issue with one of my Sea Drives.

The motor will trim / tilt up on it's own, intermittenly of course.

I thought the switch may have been defective and replaced it.

Now the motor will trim / tilt up and down on it's own.

It seems as though the relays are sticking, if it was only in one direction I suspect bad relay, but it is in both up and down. I think it is unlikely that both relays are defective.

After "jiggling" the switch it will stop running, but then returns intermittenly.

Last night the darn thing almost came completeley up while running before I caught it.

Please held to troubleshoot.

What is common in the system that would make the trim/tilt activite intermitten,ly on its own and stick on?
 

PondTunes

Petty Officer 1st Class
Joined
Jun 7, 2007
Messages
387
Re: OMC 1.6 L Sea Drive Trim / Tilt Runs By Itself

Sounds like a short that is activating the trim motor if you replaced the switch and are still having issues I would suggest checking the wiring to the trim motor.

Does it go down on its own randomly as well? Some Johnson motors have a feature that lowers them to full trim when above a certain speed.

----------------------------- Troubleshooting the switch -------------------------
A Corroded trim switch or one that has water in it could self energize.. You should be able to disconnect your negative battery terminal and try the following:

Connect ohm meter black test lead to center terminal of the trim switch.
Connect red test lead to the UP terminal and then the DOWN terminal, note the readings.
If the ohmmeter reads less than 50,000 ohms at each terminal replace the switch.

-OR-

Disconnect the red/white lead at the switch, connect the red lead to the center terminal and the black test lead to a good ground. If the meter reads less than 50,000 ohms replace the switch.
 

rkirkwo1

Cadet
Joined
Mar 31, 2006
Messages
9
Re: OMC 1.6 L Sea Drive Trim / Tilt Runs By Itself

I'll check out the switch, but I will be replacing the two relays this weekend.

I'd still be intrested in some troubleshooting advice and a better understanding of the system. The relay swap is a blind effort, I really hate swapping parts without understanding why.
 

PondTunes

Petty Officer 1st Class
Joined
Jun 7, 2007
Messages
387
Re: OMC 1.6 L Sea Drive Trim / Tilt Runs By Itself

Don't blindly swap them you can test them.


There is a demo here that shows the basic function of a relay.
http://www.bcae1.com/images/swfs/relay.swf


You can test the function of the relay by doing the following:

Remove the relay from its socket and turn it over so you can see the terminals. They should look like the diagram in the above link.

Start by setting a multimeter to check continuity.

Connect your test leads to terminal 30 and 87a, there should be continuity, because this circuit is open when at rest.

Terminals 85 and 86 are your "trigger" terminals ie they activate the relay.
use a jumper wire and connect 12 volts to terminals 85 and 86. (you may hear the relay click when this happens)

Now you should have continuity between terminals 30 and 87 and NOT at 30 and 87a.

If both relays pass this test then there is no problem with them.

If you really want to understand how this system works pick up a outboard shop manual for your engine it should cover the tilt/trim system in great detail.
 

rkirkwo1

Cadet
Joined
Mar 31, 2006
Messages
9
Re: OMC 1.6 L Sea Drive Trim / Tilt Runs By Itself

Thanks for the link, I'll test them tomorrow and post my results.
 
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