Do you think the water pump should also be changed? What is the life on it normally? I have low mileage but the X is 2004 and has most likely sat around quite a bit.

If you are doing the overhaul, then you might as well do it anyways. Along with the thermo.

Will do thanks alot and congrats on the new whip

The lower hose has a temp sensor, and the O ring on mine was shot. Had a slow drip after replacing the lower hose with original sensor until I replaced the sensor also.

Thermostat cracked
 

Thermostat cracked pulling the expansion tank off. It was already kind of tilted and then the broken piece and little spring valve popped out. Now the other half is still in there. Checked all the hoses and they seem perfectly fine. At this point I believe the leak was actually coming from that section because i found a whole bunch of sludge underneath it when I removed the bottom tray. Any ideas on taking the other half out so I don't break anything else?


So far:
Already pulled the old tank out and am ready to replace everything so I can start driving again

I'm having a hard time picturing it where those pieces fit. Can you take a bigger picture of the general area? I must be reading it wrong. You were taking the Expansion tank off and the thermo cracked? They aren't near each other.

Now you peaked my interest, off to the diagrams I go.

EDIT: Ok I got it now.http://realoem.com/bmw/diagrams/u/y/254.png

So 4, in the diagram is what is in question then. Looks like it goes in the expansion tank?

#4 in the diagram is the piece. I will be picking it up from an indy close by its about $80. That piece goes into the expansion tank on the bottom. I am assuming I have to get the old one out with some clips holding it and then nicely place the tank over it. I have not messed with it yet but I think it should be some clips around it to take it off.





**** edit - also out of curiosity when I was removing the expansion tank the silver box connecting the oil cooler pipes got loose and leaked coolant but that was during draining process anyway so it was not a problem but does it just hang on to it because there was nothing locking it into place.

That silver finned oil cooler had coolant in it? It should have oil in it.

I would change the cap too if you haven't already decided on it. It's an inexpensive part and they do wear out since they are under pressure. If you're changing your coolant reservoir anyway, order the $7 cap to go with it.

As far as your water pump, your mileage is kind of low for it but it couldn't hurt if you're doing a coolant flush. Then if you do that, you might consider changing out the serpentine belt too since you're in there. It would all be prophylactic and would give you some peace of mind but you might not even need to replace those parts.

I needed to change my belt so while I was at it I swapped out the water pump, even though there was nothing wrong with it. I did it out of paranoia that it was a plastic impeller version and would give out any minute.

I may have mistaken the oil for coolant then but didnt mess around with any of those parts. Just pushed the whole thing back into where its connecting to the radiator. Also the amount that came out looked like what was in the pipe. I had no other issues prior to this with anything else.