Ghost in Power Trim

[AndyS]

Have a 1996 50hp Evinrude with pwr trim. Located in northeast and have been hit with strong storms that removed cover exposing control console and throttle to driving rains. Engine worked fine before storms. After storms when trying to start, the engine would not start, starter would not even turn and the power trim (on its own) put the engine down and remained engaged. Battery was disconnected to prevent damage but each time the pwr is reconnected the pwr trim starts once again. the engine is equiped with a remote trim control switch on the engine. This has been disconnected but with no improvement to problem. Any suggestion would be greatly appreciated.

 

[farginicehole]

Re: Ghost in Power Trim

Sounds like water may have gotten into your control and shorted something out or maybe caused some corrosion and a bad ground to your trim switch. I'm certainly a far cry from an expert, but that's what I would start checking out unless someone else has other suggestions. Good luck!

 

[SoulWinner]

Re: Ghost in Power Trim

This just happened to my 2003 Johnson 50. The switch on the motor was corroded. It is easy to replace. Undo the plastic nut holding the switch in place, unplug the three wires and pull them one at time through the nut, then remove the switch from the motor. Mine was fixed under warrantee, so I don't how much the switch costs, but it can't be much.<br /><br />I guess these switches aren't water proof, the salt water I opperate in killed mine in a hurry.

 

[AndyS]

Re: Ghost in Power Trim

Hey, thank you for your input SoulWinner. We compleatly disconnected the switch on the motor and it didn't change anything. Do you think the trim switch on the throttle control would fail in the same manner? Would/could this also be the cause of the no start? (Or is that another issue)

 

[Hooty]

Re: Ghost in Power Trim

Sure could. There'll be two are three wires going from the control back to the t&t. One will be blue (for sky and up trim) the other will be green (for grass and down trim). Disconnect those at the control and see it that stops the phantom trimming.If it does, it's the trim switch.<br /><br />c/6<br />Hooty

 

[1986mariner150]

Re: Ghost in Power Trim

If your's is like mine (1996 150) there are two relays side by side. When mine acts up I take them both out and switch them around. Has worked every time so far. The last time mine did it I was at wfo about 65 mph and started noticing rpms increasing then more than normal chine walking then the prop pierced the surface, needless to say it stuck going up. With quickness i popped to cowl pulled the relays, put them right back in and problem went away. One other thing, do not let the hella brand and the shape of the relays fool ya. While they look exactly like driving light relays and have the same pin arrangement they do not interchange, and an attempt to do so will let a little smoke out of your harness.

 

[AndyS]

Re: Ghost in Power Trim

The saga continues. Disconnected both the trim switch at the control and at the engine. Also pulled and rearanged the relays. (thought if one relay was bad and I switched it with the other it would stay on in the up position) the result was nothing changed it remained engaged in the down position. If either of the relays are removed the trim dosent operate at all. Another clue is when the power is connected, and placing a finger on each relay, it feels like each of the relays are switching. What's the opinion that this could be caused by a bad ground? Does anyone have a schematic of this circuit?

 

[Hooty]

Re: Ghost in Power Trim

Here's a t&t schematic. <br /><br /><br />

<br /><br />c/6<br />Hooty

 

[1986mariner150]

Re: Ghost in Power Trim

One other thought comes to mind. Do you have trim control in the bow?, if so that switch may be stuck.

 

[AndyS]

Re: Ghost in Power Trim

Hooty, thanks for the great schematic. This has been great and I really appretiate your thoughts. I still havent got it working but your ideas keep me going. Because I switched the relays and have the same exact problem I'm thinking there not involved. I disconnected both trim switches and it still does the same. My thought is now that it's one of the connectors. Corrosion or moisture. The connector identified as C1 above is my main focus. I just need to find it.

 

[AndyS]

Re: Ghost in Power Trim

I got it. Basically checked all the components and found all ok. Finnaly checked wire assembly between throttle switch and motor connector. It showed a short on one end and all fine on the other. Pulled the cable and found that a critter had chewed and shorted the cable. Rewired and all OK. Thanks to all of you for your suggestions. Hooty... thanks for the schematic.