Thread: Engine watchdog

For my 300tdi Disco I've an engine saver for low water in the radiator and then I was looking at an Engine Watchdog TM2 but haven't made that purchase when I saw this. It is smaller approx 75x38x20mm and the cables are 5 mtrs. I've no association with the seller. The smaller size is appealing as I'm tight on space as well as the cheaper price but then evidently you need to purchase a buzzer to connect to it. The cable also comes out from the right side and but they told me that they could run the cable in other positions (just take a few days longer to arrive).

I'm interested if anyone has any experience with the latter sensor/monitor before I make a purchase.

Om my 300Tdi Defender I have the wire from the ignition switch to the fuel shutoff on the injector pump detour slightly through a temperature sensitive switch on the cylinder head. It opens at 105 degrees. ( 95 degree satisfactory on some diesels but goes off to readily on 300Tdi). So if head gets to that temperature, which should be well below that doing any damage, motor stops. Best to have push button that can be held down to override this so motor can still be run - most likely for just a short time eg to drive vehicle off roadway. A push button override is essential if you also have the solenoid wire going through an oil pressure switch. These operate the opposite way from oil light ones. ie no current flows through them if oil pressure below a certain level, eg 10 psi.







This type of setup is considerably more fail safe than many others. It protects the engine from overheating, whatever the cause. Not just monitoring water temperature or level. Also, some protection systems depend on the system working to stop the motor or alert the operator, which are not fail safe or idiot proof. Have heard stories of cooked motors because watchdog systems have malfunctioned or idiot drivers ignored warning buzzer or whatever. eg " I just tried to get home". If this system I use malfunctions, most likely the motor will stop - or not start immediately. Stupid things such as wire coming off terminal can cause this. Far preferable to having a more complex system that may fail to stop motor or warn operator if a wire has become disconnected and then overheating occurs.