jools182 Report post Posted May 21, 2017 I've just bought a 325ti sport I was aware it had a water leak, I am pretty sure it's the expansion tank How easy are they to change, and the more important question, how easy is it to bleed after I have changed everything? (I had a nightmare bleeding the system on a mk1 golf years ago) One last question, what is the recommended coolant to use? many thanks Quote Share this post Link to post Share on other sites
ibrahimx2001 Report post Posted May 21, 2017 Hi mate fairly easy job. Might have a bit of an issue getting the tank off the holder but with a bit of force it will come out. Bleeding ain't hard but a bit time consuming. I personally use ready mix red/pink coolant on mine which I find is good. You can find videos on YouTube on how to change expansion tank and how to bleed the system 1 jools182 reacted to this Quote Share this post Link to post Share on other sites
DaveNE Report post Posted May 22, 2017 (edited) There is a easy solution to removing the expansion tank without loosing skin ( I lost quit a bit on my e39 ) So glad a found this when I was tackling my Expansion tank on the E46 https://www.bimmerforums.com/forum/showthread.php?1756608-DIY-E46-Expansion-Tank-Removal-Made-Easy Edited May 22, 2017 by DaveNE 1 jools182 reacted to this Quote Share this post Link to post Share on other sites
jools182 Report post Posted May 22, 2017 Thanks Ibrahim and Davve It's losing a lot of water and I can't really pin down the leak. I ran it for about 5 mins yesterday while parked up and after I switched off I could hear a hissing that seemed to be around the expansion tank area. I did see a tiny, tiny jet of water, but couldn't see the direction it was coming from (expansion tank side or radiator side) I filled it up again this morning before setting off for work and after about 4 miles, the low level light was on again Quote Share this post Link to post Share on other sites
DaveNE Report post Posted May 22, 2017 Yeah sounds like the Expansion tank mate get it sorted ASAP. Me personally I would replace the cap at the same time. 1 jools182 reacted to this Quote Share this post Link to post Share on other sites
LV426 Report post Posted May 25, 2017 If you change the tank, get a genuine beemer part (£120) the cheap ebay ones can go bang sooner than you want, These cars can be a pig to bleed out, so I imagine the heater matrix was set to hot when bled and if so you are getting good heat out of it, my car drinks a lot when driven hard, although mine was pressure tested I'm sure its the gasket going slowly, I can't see any leaks. Quote Share this post Link to post Share on other sites
DaveNE Report post Posted May 25, 2017 £120 Quid? BMW Seen you coming pal I played £62 Quid about 8 months ago From BMW Quote Share this post Link to post Share on other sites
jools182 Report post Posted May 25, 2017 I ended up taking it to an independent bmw garage today. The fairly recent (cheapo) radiator was split. As the expansion tank was the original from 2003 I had that changed as well. £327 Quote Share this post Link to post Share on other sites