deedub 39 Report post Posted August 13 Replaced the battery and battery tray today in the boot ('87 E30 325i). After lifting out the original tray I noticed a plastic box underneath. Looking up what it is on realoem I found out it's the battery expansion tank. The hose on it wasn't connected to the previous battery and didn't have the elbow connector on the end of the hose either (https://www.realoem.com/bmw/enUS/showparts?id=1112-EUR-07_1987_E30_BMW_325i&diagId=61_0684#61211377835). The replacement battery I got is an SLA. From what I understand after some searching is SLA's still vent, just not as frequently (and mostly when overcharged). Does this sound right? Should I order one of the elbow connectors and hook it up to the battery? I guess it's important for a battery in the boot (enclosed and not well vented in there)? Quote Share this post Link to post Share on other sites
Olaf 3342 Report post Posted August 13 yes. 1 Quote Share this post Link to post Share on other sites
