Motor tilting up on its own

[JJJetPlane]

Not exactly sure what is going on here. Have a 2008 pontoon with Mercury Bigfoot 90 HP. Made a run across the lake, set the anchor and turned motor off, to swim with family and then all of a sudden the motor began to lift. I toggled the trim switch on the throttle back and forth but had no effect. If I held the switch in the down position the motor would stop but not go down. Finally disconnected the battery.

Reconnected the battery to head back to dock and all seemed to work fine, motor would raise and fall with the trim switch, until about half way back and the motor began to raise again while we were moving. Again holding the trim switch in the down position stopped it but the motor would not move back down. Disconnected battery, tailored by hand and the reconnected battery to raise motor for the drive home.

Any thoughts would be very helpful.

 

[iamwill1973]

Re: Motor tilting up on its own

Hard to get a reply on this site for some reason maybe the higher up members are all mechanics deeply enthralled in their repair businesses.
I am an electrician by trade and my thoughts would be first to spray some contact cleaner on the switch getting inside as best as you can also remove any connections and spray with the contact cleaner and using dielectric grease to keep the moisture out if all else fails maybe check the relay that powers the tilt/trim pump and make sure it is functioning properly.

 

[Charlie61]

Re: Motor tilting up on its own

check your oil in your trim pump sould like your bleeding off one of the cyc holding in place or maybe water in it chaeck that first sorry can't help more

 

[Chris1956]

Re: Motor tilting up on its own

Will you are on the right track. I have seen water get into rocker-type switches and do that, but not to the extent you describe. That motor likely has a two wire motor and a set of relays. Maybe the up one gets stuck? When she starts tiltiing, and you push the switch down, you remove the ground from the tilt circuit, stopping the tilt.

 

[Silvertip]

Re: Motor tilting up on its own

If the switch doesn't operate the motor and the motor rises or falls under pump motor power by itself, you can bet there is a bad relay. Relays that stick generally require removal of power in order to release. That said, a switch that is going bad can cause the problem but intermittent operation would typically be the problem with it. Disconnect the switch and use an ohm meter to verify its operation. If there are two identical relays (check part numbers) on the motor, swap them and see if the problem changes. If it stays the same the switch is suspect. If the problem changes, the relay is the likely cause.

 

[DNLBOONE]

Re: Motor tilting up on its own

Sounds like the same problem i just had. I changed both relays and kept the old one as a spare. Should be the up relay. Blue wire up for sky. Green wire down for grass. Fixed my problem hope it does yours.