Hello

[DonB]

I'm in my fourth year with a ZD21 and 60" Pro deck. It's right at 280 hours and has been a fine and economical and agreeable machine (except for the safety interlock system).

My engine had a little encounter with a stick the other day which stripped off the fan belt and removed the little thingy off the bottom left rear of the radiator that was probably called the drain plug. Anyway, I have some issues to work through and need to ask for a little info. The engine is just fine but it seems my overheat warning buzzer has quit working since this accident occurred. How would I test and troubleshoot that little jewel?

Thanks,
Don

 

[ETRon]

Hi,

Welcome to the Forum, I'm new here as well. I'm sure someone familiar with you specific model will be much more knowledgable than I but being a long time mechanic I can offer some generic info. First though I'd ask why you think the overtemp sensor is faulty? The only way I know to check one is to actually remove one, heat it to it's set temp all the while checking it with an ohm meter. When it gets to temp it should go from infinite to zero ohms. From personal experience if it really is suspect it's easier just to replace one. One more tidbit though most people don't always realize.... if you loose coolant to where the sensor is uncovered, it will not warn you or reflect the tru temp of the motor usually until it's much to late.


Ron

 

[DonB]

Hi and thanks for the reply Ron.

Ultimately, I suspect something is faulty with the overtemp warning system because I covered the radiator and ran it up to the point I figured the alarm should go off. It didn't.

Am I correct to assume a fault either has to be the warning horn itself, the sensor screwed into the upper radiator hose housing or the wiring in between?

Edit: I grounded the horn and it works so I guess that leaves me with a bad overheat sensor.

Don

 

[KubotaTech]

That is usually how I test the system, if you ground it and it works, the circuit is ok and it only leaves the sensor