NS90A slow trimming down, wire to motor getting hot and smoking

[younggun]

I have a 90 2 stroke on one of my boats. Trim has gotten very slow going down. It is still normal speed going up. I noticed when I held it down for a couple seconds(about half way down) the wire gets so hot it starts smoking. The jumper power wire to the relay gets very hot along with the wire to the motor. I changed the jumper and still the same thing happening. Changed the relay and same thing. I’m stumped other than motor is going bad? Just odd it’s only one way and down at that which should have less load. Any advice is appreciated

 

[alldodge]

Have no knowledge of these OB's, but hot wires and smoke means something is shorting out. When current increases (what happens when shorts happen) then the wire sized for the motor is drawing more then designed for.

It's most likely the trim motor. Reason being is the relays just pass voltage to motor and draw very little current.

 

[younggun]

Have no knowledge of these OB's, but hot wires and smoke means something is shorting out. When current increases (what happens when shorts happen) then the wire sized for the motor is drawing more then designed for.

It's most likely the trim motor. Reason being is the relays just pass voltage to motor and draw very little current.

That seems to be where I’ve narrowed it to in my thoughts too. Guess I’ll be ordering a trim motor.

 

[MattFL]

If the wire is smoking hot, either the wire is corroded through, or the motor is drawing a lot more power than it's supposed to. The second option is more likely I think. Get yourself a DC current clamp and measure how much current it's taking when trimming up and down. Down should in theory be less than up because gravity is helping, but I suspect down will be significantly higher than up. If so, then it may be a motor issue.

 

[pvanv]

A poor connection could do that.

 

[MattFL]

A poor connection could do that.

Good point. Since he didn't specify the end of the wire, I took it to mean the majority of the wire was smoking. But now that I think about it, shouldn't it be fused? Meaning surely the fuse would burn before the entire wire got hot enough to smoke. So I think your idea of a loose or bad connection is most likely.