406 hdi 110 coolant loss

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Wed 22 Jun 2005 22:56
406 hdi 110 coolant loss - area1
I have a 2002 406 HDI 110 which is loosing coolant pretty fast while driving. It seems to loose it out the expansion bottle and the needle sits at 90 all the time on the temp gauge on the dash. This is with a new thermostat fitted too.

I can loose about a litre of water in about 15 miles or so now. It has got progressively worse as the last week has gone on.

Is it common for water pumps to go wrong on these engines, meaning that the water isn't pumped around properly and therfore is getting too hot, causing the pressure to build and it blow the water out the cap?

Any thoughts would be gratefully appreciated.

Thanks in advance

Andy
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Thu 23 Jun 2005 09:16
406 hdi 110 coolant loss - Collos25
head gasket
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Thu 23 Jun 2005 10:09
406 hdi 110 coolant loss - Canuck
Did you bleed the air out of the cooling system using a header tank on the reservoir after changing the thermostat? If the air was not removed, then it will overheat. Any significant overheating can easily blow the headgasket so you may be stuffed already, but I would try bleeding the air out if you haven't done so already.
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Thu 23 Jun 2005 13:37
406 hdi 110 coolant loss - Martin1981
Could be a faulty pressure cap. Try replacing it and see what happens then. If the pressure cap is faulty, the coolant will not be pressurising sufficiently and the temp will run higher than usual. Losing a litre of water in 15 miles is one hell of a lot. If a new pressure cap doesn't solve the problem, run the engine with the cap off and if bubbles are present in the tank within a short space of time, then it's more likely to be head gasket failure, which would allow compression from the engine to enter the cooling system, causing bubbles and high pressurisation. Therefore the only way out would be a new head gasket.

Regards
Martin
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Thu 23 Jun 2005 14:43
406 hdi 110 coolant loss - madf
IF the head gasket has gone, you should have the head skimmed as well to ensure it is perfectly flat. If not, all you will get is another HGF in a few 000 miles.

You can tell a HGF even more simply (and safely).
Feel the top hose with the engine switched off. It should be flexible.
Now start the engine and let it idle. If the HG is gone the hose will feel stiff due to the pressurising effect of the exhaust gasses on the water system.

(best done when engine is throuughly warmed to operating temperature)

madf


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