Hitachi Zaxis 210 False Overheating Problem

[digdigger]

Hi,

I'm a newbie in this forum. I have a 2007 Hitachi Zaxis 210. While working, every 30 minutes, the temperature meter will go up, reaching the maximum. However, the actual temperature of the engine and radiator water is normal, no sign of overheating at all. These were things that we had done:
- Change cylinder head and gasket head
- Serviced radiator
- Change sensor thermo
- Injection pump timing is correct
- Injection pump nozzles are okay
- Change monitor
- Tried making a new circuit line from sensor thermo directly to the monitor. Still, it didn't work
- New water pump
- Cooling system is okay
- Switch overheat is okay

Curious over the false ovearheating alarm, we tried working the excavator for an hour after the overheat buzz, the engine still works normally. (no power dropping or stalling). I'm running out of ideas of what the possible culprit could be. Really need your help to solve this problem. All ideas are welcome. Thank you so much for your help.

 

[tool_king]

have you tried replacing the sensor again?

 

[digdigger]

We replaced the sensor thermo after we tried working the digger for an hour after the overheat buzz. Please kindly advise why we need to change the sensor again.

 

[cutting edge]

Ive seen corrosion problems at the connector at the back of the cab (X1 maybe?) cause weird problems....mostly with the can circuit though.

Worth a look there and at the connectors under the engine.

 

[tool_king]

digdigger
Because you might have bad sensor .You stated (Tried making a new circuit line from sensor thermo directly to the monitor. Still, it didn't work ).I have had new sensors fail right out of the box.

 

[rgl726]

Temp monitor sensor and overheat sensor are 2 different sensor. Did you replace both of them?

 

[digdigger]

I will try all of your suggestions and will give an update. Thanks a bunch!!!!