TD5 overheating problem...

Hi, i have a disco td5 and it keeps overheating intermitently. Have had radiator replaced 2months ago, thermostat replaced 2 weeks ago. Its been pressure tested and no coolant leaks from anywhere. Can drive for ages no probs then all of a sudden loss of power and temp guage goes right up. Sometimes if i put the fan on full, temp comes down and when this doesnt happen all coolant has been chucked out of tank! If i fill it up again can drive again for ages without any problems! Any ideas as to what this could be, am going mad.....

craigmc said:

Hi, i have a disco td5 and it keeps overheating intermitently. Have had radiator replaced 2months ago, thermostat replaced 2 weeks ago. Its been pressure tested and no coolant leaks from anywhere. Can drive for ages no probs then all of a sudden loss of power and temp guage goes right up. Sometimes if i put the fan on full, temp comes down and when this doesnt happen all coolant has been chucked out of tank! If i fill it up again can drive again for ages without any problems! Any ideas as to what this could be, am going mad.....

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Working on the basis that it's not head gasket, the next obvious area would be an airlock somewhere in the cooling system.

Did you refill the radiator from the header tank or the top of the rad. Have you tried bleeding the system using the black screw on the top hose to the right of the engine?


If this doesn't work, then I would be getting the coolant "sniffed" for exhaust gases, by a competant garage.

Hi, a garage replaced both the radiator and the thermostat so presume it was done in the correct way. Also sometimes i can hear trickling water when i accelerate..... Have had couple of garages look at it and no luck as yet!!

craigmc said:

Hi, a garage replaced both the radiator and the thermostat so presume it was done in the correct way. Also sometimes i can hear trickling water when i accelerate..... Have had couple of garages look at it and no luck as yet!!

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When this happened to me it was the head gasket. LR dealer (it was under warranty) pressure checked it and told me they couldn't find a problem. Insisted I go away and drive it and "if it breaks down we'll relay it back".

It was the gasket. They eventually did it under warranty. Badly. Using plastic dowels. Later on the head cracked. I reckon that was their fault.

The trickling water noise is strange - the only place it could come from methinks is the heater. Could you have a heater matrix leak that's causing you to lose coolant and overheat? Or it may be that the heater has an airlock as a result of the garage's work. This wouldn't cause overheating but might explain the noise: does the heater work OK?

It sounds like headgasket to me too.

If you squeeze the coolant hoses after a drive are they rock solid?