Temp head sensor importance

[Fishfinatic]

So I have a JR30RESS I’ve gone through basically the whole motor and discovered the temp sensor is unplugged from the ignition coil, it looks like it’s been unplugged for a bit, showing signs of corrosion a little in the plug end. After seeing this I checked the compression to make sure there was no resulting problems that might have been caused by someone’s eagerness to by pass this switch rather than fix the issue at hand. I’m changing the thermostat and water pump as I think anyone would when obtaining an older motor just as standard measures for proper cooling. I have a temp gun and tac meter to check engine temp once I change these items and clean any water cooling passages that may have been blocked over the years. My research tells me that if the motor is running over 160F at 5000 rpm, then the contacts will close and limit rpm to prevent damage. My question is, does an alarm sound on the motor itself or only in a key remote throttle unit, or does it just cut the rpms and not signal it’s doing it with an alarm on the actual motor. I definitely don’t want to hear the alarm after changing thermostat and water pump.. she smokes some but I think it’s related to be slightly rich in fuel or carbon build up which I’m going to give it the engine tuner treatment, I’m sure it’s never been done seeing the original condition I got it in, probably change plugs again after..

 

[juno pierrat]

you maybe able to test temp alarm by , with key on, ground the tan wire the goes to the sensor

 

[jasper60103]

... My question is, does an alarm sound on the motor itself or only in a key remote throttle unit, or does it just cut the rpms and not signal it’s doing it with an alarm on the actual motor. I definitely don’t want to hear the alarm after changing thermostat and water pump.. she smokes some but I think it’s related to be slightly rich in fuel or carbon build up which I’m going to give it the engine tuner treatment, I’m sure it’s never been done seeing the original condition I got it in, probably change plugs again after..

I doubt the motor itself has a built-in alarm. The powerpack monitors the cylinder head temperature (or when the sensor trips), it will govern accordingly.

 

[Fishfinatic]

Ok maybe that’s why it wastakrn out of the equation... I’ve read nothing on alarms on the motor so figured i would ask if someone knew, thanks for the responses, greatly appreciated