Engine Coolant Leak

[MuhammadK]

Leak on floor
Leak underneath car

I have noticed some terrible coolant leaks and have been getting requested to top up my engine coolant frequently. Anyone know what could be the source? I’m looking to DIY a fix if possible. Seems to be happening just above the skid plate.

[Sundayjumper]

Did you fix this ? I had a leak from this hose - part 11537843273, #12 in this diagram:

https://www.realoem.com/bmw/enUS/sho...diagId=11_5036




It fell apart completely when I removed it, as you can see. You could probably bodge it with a length of generic hose.

While I was doing that, the right-angle bit that joins onto the water pump broke too:




Not available from BMW on its own, you have to buy the entire return line 11538092641. A guy on ebay sells the connector for £37 which is 😮 but still less than the whole thing from BMW.

https://www.ebay.co.uk/itm/177205290532

It's just one of these, €17.91:

https://www.iq-parts-shop.com/en/nor...-12-10-mm.html

But the shipping & tax makes it almost that much to buy them singly so I paid the £37 from ebay.

And while you're there, you may as well put a new thermostat in. I'm not getting into the low temp thermostat debate 🤣 but pretty much every car I've ever had has run better with a new thermostat. Even if there's been no obvious problems, a new thermostat just behaves better.