'89 70 hp hot horn

[schifsky]

The hot horn on my 70 hp Evinrude intermittently sounds when the engine is not hot. It's pumping plenty of water through the hole at the back of the engine housing.<br />Mike S

 

[DJ]

Re: '89 70 hp hot horn

Carefully touch the top cylinder head when this happens. Can you hold your fingers there for a few seconds? If so, it probably is not hot.<br /><br />The horns do go bad. You can test it by touching the tan heat sensor wire (on head, with key on) to a good ground (engine block).

 

[sooke]

Re: '89 70 hp hot horn

I just had the same problem and it was a short in the horn. Once replaced it was fine.

 

[seahorse5]

Re: '89 70 hp hot horn

Is it a steady tone, a chirp, or a beep every 30 seconds?

 

[badbill]

Re: '89 70 hp hot horn

The same thing happen to me with my 78 55hp Johnson. I had trash behind the thermostat. I removed the water jacket cover replaced the thermostat and gasket. My cylinder head was hot as DJ stating that is what made me start looking at the thermostat.

 

[marinemech]

Re: '89 70 hp hot horn

make a note as to horn sound is it steady or beeping every 1/2 second or beeping once every 20-40 seconds or low pitched whine could be fault in oil tank vro pump or boat check battery grounds<br />disconnectone at a time:1 oil tank wires brown wire usually near starter 2 vro wires three or 4 pin connecter coming out of vro pump 3 and temp sensor brown wire out of cylinder head<br />if temp sensor isthe culprit have dealer look up the service bulletin on false overheat warning and replace temp sensor with the one recommended brown/blue wire i think the part number is 584995 but am unsure