MYSTERIOUS OVERHEATING ISSUE

[Nickincabin]

My LR DEF 90 has exhibited a strange overheating issue over the last year. Whilst I am driving (low or high speed) the temp gauge will occasionally move to the right, stopping short of the red. over last 12 months I have replaced: radiator, water pump, thermostat, even the gauge. The guys who do my lady's and my vehicles have carried out all tests and say it cannot be the head gasket, and not to worry....obviously it bothers me! Anyone out there got a thought? The new gauge has condensation in it. Grateful for any any advice

 

[miktdish]

Is the sensor in the engine a black or green one ?

https://www.ebay.co.uk/itm/204738086489
https://www.ebay.co.uk/itm/201949613614

 

[Nickincabin]

Pardon my ignorance, what difference does it make?

 

[Phill]

The sender must match the gauge or you'll see fake readings. Usually overheating when it isn't.

 

[Nickincabin]

The sender must match the gauge or you'll see fake readings. Usually overheating when it isn't.

 

[Nickincabin]

Ok thank you. Will talk to Simon, my mechanic tomorrow. A guy at a power station where I was delivering a course today talked about Kenlowe fans. Any opinions?

 

[Nickincabin]

Sender or sensor?

 

[Anaconda]

Sender or sensor?

Same thing, sensor unit.
Have you actually checked the temperature ?

 

[Nickincabin]

Indeed not...will look into it. Thanks

 

[miktdish]

Pardon my ignorance, what difference does it make?

"DEF 90 has exhibited a strange overheating issue over the last year" - it causes this.

You don't need a mechanic.
Look at the sensor which is under the thermostat housing on the front left side of the engine.
Buy the other colour unit, ie if it's Green buy a Black one or if its Black buy a Green one.
With a cold engine ...
Ignition off
Unplug the single wire (it pulls off)
Put the new sensor on top of the engine so you can grab it quickly.
Use a 10mm (or 11mm i can't remember) socket.
Take out the old.
Fit the new one as quickly as possible (minimising fluid loss).
Go for a drive/heat up the engine ....

A 5 min job

 

[Nickincabin]

Nice one, thanks. will have a go tomorrow as today have many a chore for 0A...

 

[Forrest Gump]

Nice one, thanks. will have a go tomorrow as today have many a chore for 0A...

Had same issue as you. Did basically what Miktdish has said above. It worked. Had wrong sensor put in.