94 Merc 75 Continuous Beep

[acollins74]

My OH alarm will not turn off. Not even in the driveway when engine is cold.

I have lotsa posts that say were the wire is that I can test but I can not find the Tan Wire?

Can someone help me find the wire and offer any advice.

Here are some images of my engine with the cover off:
http://www.mustachenation.com/BoatEngine/Side2.jpg
http://www.mustachenation.com/BoatEngine/Top.jpg
http://www.mustachenation.com/BoatEngine/Back.jpg

 

[acollins74]

Re: 94 Merc 75 Continuous Beep

I found out which wire.
The Tan wire with the blue stripe.


If I tug on the wire coming out of the back of the engine to the left of the Plugs Pictured here.
http://www.mustachenation.com/BoatEngine/Back.jpg

then the alarm stops sounding. But as soon as I stop pulling the wire, the horn beeps again.

What should I do next?
also, How hard can I pull this wire before it breaks off. I'm pulling pretty hard.

 

[acollins74]

Re: 94 Merc 75 Continuous Beep

I followed the tan/blue wire from out of the rear of my motor to where it was screwed into a black plastic cube looking object along with two other wires.

If I remove the tan/blue wire from the bundle, the alarm stops.

Does this mean this wire is bad? How do I remove/replace this wire from the rear of the engine, It seems to have a rubber plug into the back of the motor.

 

[CharlieB]

Re: 94 Merc 75 Continuous Beep

The rubber plug is a seal to keep water out of the sensor, it sometimes sticks. You can try using a very small screwdriver, like for eyeglasses, poke it in alongside the rubber all around to loosen the stuck seal.

A new sensor comes with a new seal.

 

[acollins74]

Re: 94 Merc 75 Continuous Beep

I will try the screw driver trick this weekend and hopefully I can get it out.
Once the seal is essentially 'unstuck' should the plug come out fairly easily. I know I was pulling the heck out of it on Sunday and It wouldn't budge.

I also looked up the sensor online to purchase it in advance and it seems there are two versions so once i get it out, I can order the replacement. I hate missing another weekend on the water but I suppose its part of the game.

 

[acollins74]

Re: 94 Merc 75 Continuous Beep

Fantastic. Got the sensor out. It was a wire that had what looked like a watch battery on the end of the spring that went into the motor but it still cost me Fifty dollars plus Handling.

Thanks for the screw driver trick. that was all i needed to do to loosen it up enough to pull right out.

Got the replacement part in on Friday and installed without issue. No more continuous beep. Thanks everyone for your help and suggestions.