Wiring problem

[bonita14]

We have a problem with our 91 Mercury 75 horse on a Monarh boat. We ran our boat for about 45 minutes first time out. The alarm systen began to sound a steady ring. I was told it could be the water pump or the sensor. Water pump is replaced.<br />Ran the boat about 1 hr and the alarm sounded aain, continued to run boat and noticed a good deal of smoke under cowel near ignition. The wire that goes to the gas tank is melted. Ken cut the wire therefore gas gauge doesn't work and radio doesn't work. Would a bad censor cause this problem and where is the censor loated?<br />Any help would be appreciated.

 

[kdmiller8251]

Re: Wiring problem

Do you have a temperature gauge?? I believe some boats have alarms if temperature goes up real high.... Something to look at...<br />Tallman

 

[Charger183]

Re: Wiring problem

You might have a dead short at the tank sender unit, and the radio was on the same line. The heat sender wouldn't cause this, but it may be reading a hot spot caused by a vapor lock in the engine cooling system.

 

[Charger183]

Re: Wiring problem

Sorry. Forgot to say that if the heat sensor wire insulation is warn through and the bare wire touches a ground, the alarm will sound.