Replacing Coolant Reservoir
 

Can anyone give me a hint on how to remove and reuse the coolant level sensor at the bottom of the reservoir? Thanks in advance. Ben

I did this job last night - it's easy to get the sensor out once the expansion tank is freed - just twist the sensor (blue part) round 90 degrees anticlockwise and withdraw from the tank.

The fluid was still boiling hot some hours after last driving, so I'd advise doing this in the morning or with thick gloves... pulling the big hose off the bottom was the tricky part for me

I've had instances where the old level sensor leaks when installed into a new reservoir. for this reason I just get a new level sensor. An original BMW sensor is about $13 anyway so might as well.

and speaking of original...the hella/behr china made reservoirs lasted me 11months on my E39 with less than 6k miles of use. Since then Ive replaced it only with original BMW...

Biglion,

Thanks a million for the counterclockwise hint. It saved a sensor. I performed the swap this morning. Hint for others: be careful with the 8mm plastic return pipe at top. I managed to break mine during removal and gave to patch until I get replacement part. If you don't pry exactly under the attachment, you will like I break the fragile plastic pipe.

No problem my friend - I just need to go down to the garage with a paperclip as I managed to drop one of the fastners down into the engine bay... will be getting an original from the breakers' yard later

its good to have the plastic prying tools to remove the hoses gently placing leverage between the plastic tube connector and the old reservoir rather that by pulling the rubber hoses