My coolant sensor got pulled out when I was working on my cam chain tensioners but no fluid leaked out of the hole. The sensor sure looks like it lives its life bathed in coolant.

Running, not running and with the coolant topped up this hole leaks nothing. How is this possible?

Thanks
Eric

 

The sensor detects the float inside the tank, magnetic if I remember correctly. The sensor just plugs into the tank.

 

That makes sense. It's not a Lucas part so I knew it wasn't magic.

Thanks

Eric

 

The sensor (magnetic reed switch) is isolated from the coolant in a tube integral with the tank. The magnetic float rides on this tube and when lower than the switch allows the switch to open.