overheating disco 200tdi

hi all,having a bit of trouble with my disco.have fitted a new radiator,thermostat and water pump to my disco(about 2 months ago).was running fine and temp gauge seemed ok.went out on sunday with an empty car trailer on the back,i noticed the temp gauge went 3/4 way up while doing 65mph on the motorway.i slowed down to 50 and the gauge went higher so put the heater on to hot,the gauge came back down to 3/4 .it is not pressurising the cooling system.am getting abit stuck now.does anybody have any ideas.
thanks.

Are you sure you havn't got an air lock ?

Hope for an airlock but I would check your stat.
I recently bought a new one unfortunately it was made by ****part.
It didn't work and cooked me motor!
Head now off!

i re bled cooling system yesterday to make sure ther was no air in system.have been out in it today and temp gauge still reads 3/4.

doris.girlracer said:

i re bled cooling system yesterday to make sure ther was no air in system.have been out in it today and temp gauge still reads 3/4.

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Is the coolant tank pressurising excessively (can you hear it hissing)?
If so your headgasket may be leaking slightly

no its not pressurising,all parts that were fitted are genuine landrover not ****part!!!

Do you still have the viscous fan fitted? may be worth checking

viscous fan is ok put a new one on after it fell in bits.

doris.girlracer said:

no its not pressurising,all parts that were fitted are genuine landrover not ****part!!!

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That just means ya paid 5times more for parts that were probably made in the same factory in china.

Test stat by hanging it in a kettle of water and waiting for the water to heat up stick a thermometer in the kettle to see what temp the stat opens at.

check all hoses for leaks whilst engine Is running and hot.

what lead you to change all these parts? other than the fan falling apart?

its just as easy to feel top hose it gets hot when stat opens

i changed rad because fan went through it when it fell in bits,water pump because it was leeking and there wasnt a thermostat in it.an not bothered about price of bits they all go through my business.

strange there was no stat in it, maybe someone else had the same problem before, what temp did it run at before these problems?

just below halfway.

dont rule out bits just cos they are relitavly new... even oem parts can fail.

is the outside of the rad clean ....in the past ive had a blanket of fluffy dandelion seeds completely blocking the airflow through the rad causing overheating ....if you aim a garden hose at the rad the water should go straight through the fins between the cores... if it bounces back and washes yer face the airways is blocked.

job sorted now,it was the metal water pipe that runs across the head.it was blocked with ****e!!!