Overheat alarm in with motor not running

[WATEREDDOWN17]

This morning while out fishing, I used my trolling motor for about 3 hours after I ran my 96 Mercury 90 HP 2 stroke to my area. When I attempted to move, I went to crank my motor, and when I put it in what I guess would be the ACC position, it gave me the overheat alarm. (constant beep). Again, motor hadn't been run in 3 hours. Still turned it all the way on, and motor was peeing fine, no grass or anything on prop. My question is: I am sure this COULD be just a bad wire, but, with it peeing the way it is, could it be a bad impeller as well? It ran to my spot fine. Just want to gather some more info before I call a mechanic. Thanks.

 

[Sprky]

Re: Overheat alarm in with motor not running

Float in oil tank is saturated. Find the blue wires comming from the float sensor and disconnect one of them. If your alarm quits, you will most likely need a new tank as the float is non replaceable.

Chris

 

[WATEREDDOWN17]

Re: Overheat alarm in with motor not running

I add the 2 cycle oil straight to the gas for this model. Therefore, would I still have an oil tank?

 

[Sprky]

Re: Overheat alarm in with motor not running

Is there a tank on the motor?

There is a sensor on the water jacket near the plugs on the back of the motor. Disconnect it and see if your alarm stops.

The only two alarms on that motor are low oil (tank) and overheat.

 

[WATEREDDOWN17]

Re: Overheat alarm in with motor not running

There is no oil tank on my motor. (My buddy has a 150 where I think he adds his separately, 2 stroke also. ) Now, it doesn't do it consistently. It is the overheat alarm, where it is constant. However, I hooked up some water to the intake, ran it at the house a couple of times, and there are times it would sound the alrm, and times not. The motor and the lower unit both didn't feel abnormally hot (I live if central Florida), so I am starting to think short. You mentioned a wire, and there is a wire, I think pink or light orange in color, above the top plug that is just there. It looks like somebody cut it, but it has been like that since I got the boat a year ago.

 

[j_martin]

Re: Overheat alarm in with motor not running

There is a single wire from the motor to the alarm itself. When it is grounded, the alarm sounds.
It is normally grounded, in your case, only by the overheat switch on the head. It can also be grounded by getting pinched somewhere, mouse bite, etc.

The circuit color code is tan. If there are 2 tan wires, it's the one with a blue stripe.

 

[WATEREDDOWN17]

Re: Overheat alarm in with motor not running

I'm going to head out back and see what I can find. I'll report back later. Thanks for the help, guys!

 

[WATEREDDOWN17]

Re: Overheat alarm in with motor not running

Went out and saw the tan wire you're referring to. The one with the blue wire runs into an 8 prong harness. When I disconnet the harness, beep is gone. Wehen I checked the huge wire that the harnessgoes into that runs to the throttle, it looks old and like something burnt in a spiral pattern for a foot or two. I assuming that is the culprit. My question now is, is that a part I can purchase and replace? It looks to be 6-8 foot long, but it goes under my flooring so difficult for me to tell exactly, and do you know how much it will run?

 

[Sprky]

Re: Overheat alarm in with motor not running

Must be Force by Mercury. Harness is available from Mercury, or maybe somewhere on this site.

Cut the damaged area open and see if you can make repairs.

Solder and shrink tubing go a long way...... It ain't rocket science.

Chris

 

[WATEREDDOWN17]

Re: Overheat alarm in with motor not running

Not a Force. I thought about cutting out the damaged part, but what would the other 7 wires go to? I think 1 or 2 of them are closed, I just don't want to create another problem. I am going to order the manual for my motor.

 

[j_martin]

Re: Overheat alarm in with motor not running

If you have room to cut out the damaged part and splice the wires back together color for color, you don't even have to know where they go.

Know this, if in that burn spot power gets into the kill circuit, yer in for expensive repairs.

 

[Sprky]

Re: Overheat alarm in with motor not running

Unless oil tank was removed, it is a force.