Coolant loss no leak found

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Tue 27 Sep 2022 21:45
Coolant loss no leak found - Redcar01

Hi All

I have a coolant leak first noticed had to 500ml in topping it up to max, then 250ml the next day and every 2 days or so its below min and have to top up. I cannot see any leak.

its a BMW X1 1.5 petrol I cannot get it into the dealers for 3 weeks so having to keep topping up

any ideas pleas whats wrong

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Tue 27 Sep 2022 22:25
Coolant loss no leak found - Brit_in_Germany

There was a massive recall of diesel engined car because of the egr valve leaking coolant leading to a fire risk due to the glycol. Maybe the petrol engined versions are suffering too.

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Tue 27 Sep 2022 22:41
Coolant loss no leak found - bathtub tom

Any dead cats round your way? They love coolant and will lap it up, despite it being toxic to them.

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Wed 28 Sep 2022 01:01
Coolant loss no leak found - Crickleymal

It's difficult to tell. You could have a leak, you could have a blown head gasket or a damaged radiator. I'm sorry I can't be more definite.

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Wed 28 Sep 2022 09:18
Coolant loss no leak found - Andrew-T

Could be alll kinds of things - there are lots of places in the coolant circuit where a leak could start, plus the header tank and the heater matrix. You have to look for drips on the ground, stains on the block, anything.

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Wed 28 Sep 2022 09:26
Coolant loss no leak found - Adampr

If there is no coolant visibly leaking (on the ground or in the engine bay) your most.likely culprits are the radiator cap or head gasket. First step is to visually check the cap. If knackered replace. Second step is to check the oil for 'mayo' or other discolouration. If both of these are clear, maybe replace the cap anyway. After that, it's off to the garage for a pressure test.

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Wed 28 Sep 2022 09:26
Coolant loss no leak found - catsdad

Check under the oil filler cap for mayonnaise like scum. It’s not conclusive proof of a failed head gasket but it can be indicative.

Also it may not apply to BMWs but I’ve had cars where the heater can leak behind the dash and drip into the footwell, so check them for damp.

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Wed 28 Sep 2022 12:00
Coolant loss no leak found - 43576

My had same issue, it was steam out of my exhaust, the coolant was bubble smell of diesel fume it was head gasket leaking. Look if there are any steam out of exhaust when the engine is warm.

Edited by 43576 on 28/09/2022 at 12:01

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