Heat Sensor for a yamaha 90 two stroke outboard

[lawhon11]

where are the heat sensors for a 90 yamaha two stroke and where can I go to see a pic of them.

 

[robert graham]

Re: Heat Sensor for a yamaha 90 two stroke outboard

where are the heat sensors for a 90 yamaha two stroke and where can I go to see a pic of them.

Looking at the back of the motor with the cowling off, upper right side of cylinder head you'll see a small black rubber plug with a wire coming out of it. The sensor/plug is held into the head with a small metal clip and small bolt. You can remove the sensor/plug by removing the bolt and clip and just pulling it carefully outwards towards you. Good Luck!

 

[lawhon11]

Re: Heat Sensor for a yamaha 90 two stroke outboard

OK I think that the part in the pic is the temp sensor. What I was getting is a continous alarm when i turn the ignition key to crank or even when i just turn the ignition key to ac. when i unplugged this part from the motor though the alarm did not stop, however it did stop when i unplugged a wire leading to this part. Any suggestions.

 

[99yam40]

Re: Heat Sensor for a yamaha 90 two stroke outboard

Easy to test with an ohm meter, should be open while cool and close when heated up around 200F