BMW 3 Series Compact E46 318iSE - BMW Coolant loss

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Mon 29 Jul 2013 14:25
BMW 3 Series Compact E46 318iSE - BMW Coolant loss - mspaff

The low coolant warning light came on and I topped up the radiator with about a pint of water. Very soon after the warning light came on again and the level indicator top was level with the filler neck top. After driving a long way, keeping a careful eye on the temperature gauge, the next morning it just needed a pint to top up but then soon lost that pint. What is going on? There are no obvious leaks and there is no 'mayonnaise' under the oil filler cap so hopefully the head gasket is OK.

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Mon 29 Jul 2013 17:36
BMW 3 Series Compact E46 318iSE - BMW Coolant loss - Peter D

Most garages have the kit to detect combustion gases in the header tank. So have it tested. Is this an automatic gearbox. Regards Peter

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Mon 29 Jul 2013 17:38
BMW 3 Series Compact E46 318iSE - BMW Coolant loss - Peter D

Get the car upto temp when it is dark then search the bonnet area and radiators with a high powered light. You may se stream, water vapour. Regards Peter

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Mon 29 Jul 2013 21:16
BMW 3 Series Compact E46 318iSE - BMW Coolant loss - Collos25

HG is a very very common problem on all BMWs especially the 4 cylinder engines more than likely the cause other problems are the water pump mounted on the engine side and gear driven you will not see a leak coming from the bottom of this unit .Also look very carefully at the radiator.The fact there are no tell tale signs is meaningless they are sometimes evident but more often than not they do not occur.

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Thu 1 Aug 2013 15:27
BMW 3 Series Compact E46 318iSE - BMW Coolant loss - mspaff

Thanks. I'll have the header tank checked for engine gas. As the car is 2001 I guess it will be the end of it if it is. I have come across a treatment claimed to cure head gasket problems. It is put in the radiator. Does anyone know if it works?

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Thu 1 Aug 2013 15:20
BMW 3 Series Compact E46 318iSE - BMW Coolant loss - mspaff

Many thanks. It is a manual gearbox

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