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Old 2nd December 2019, 16:46   #61
kaiser
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Not by a factor which would keep the coolant below the opening temperature of the thermostat! The heat loss through the matrix is minuscule compared with that generated and dispersed by the radiator and its fan.

Simon
Define "minuscule" and provide some relevant references for your claims, please.
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Old 2nd December 2019, 20:41   #62
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Define "minuscule" and provide some relevant references for your claims, please.
Think about the comparative surface areas, the fan sizes and the function of the two heat exchangers. I'm surprised that you need "relevant references". It's surely obvious to someone with your level of engineering appreciation Kaiser.

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Old 2nd December 2019, 22:10   #63
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In post no. 33 Jim gives more detail which may be of interest.

Alan; I think you're allowing your familiarity with the diesel engine to colour your judgement. None of the factors you mention affect the warm-up time of the KV6 to any material degree. It will produce enough heat to open the thermostat over about a couple of miles. If it is cooled to 88 degrees, by whatever means, the thermostat will close again. It's a regulatory device which prevents the temperature dipping to the values which Jim has reported. There is only one reason for that and it's not supposition.

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Originally Posted by SD1too View Post
Not by a factor which would keep the coolant below the opening temperature of the thermostat! The heat loss through the matrix is minuscule compared with that generated and dispersed by the radiator and its fan.

Simon
My familiarity with the diesel is not clouding my judgement. My comments are based on experience of a controlling the heat in a few petrol engines in the past that were leaking coolant catastrophically (not the 2.5 here). However as the laws of physics have not changed in millennia, I can only assume my experience of trying to stop these heads from boiling over the principles would still apply safely and with ignorance.

If your car is overheating and you need, for whatever reason, to control the rise, you switch on the heat with blower on max, and reduce load on the engine, by maintaining a constant engine speed. By driving with the heater on, it will slow down any engine heat build up, and a continuous speed of an engine will maintain and potentially lower the temperature if it is moving in clear (and particularly cold) air.

Your argument of not having the thermostat opening is moot, without additional background. To add to the previous data required, there is no mention of opening temp of the new stat fitted - is there such a thing as an 84 degree stat for the V6, perhaps even for alternative models, such as the Freelander or ZR etc?

There simply are too many variables not accounted for to leap in and condemn components. (just as there are too many variables for a belt manufacturer to allow for and therefore err on the side of caution when recommending replacement times!). If you can account for these variables, you can then make judgements based upon them. If you cannot account for them, then you cannot make a judgement/diagnosis.
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