Hose connected to battery in C230K

[Pete]

My original battery has been in use for 4.5 years, so I figured that it was time to replace it. When I replaced the M-B battery, I noticed that there is a (drainage?) hose that connects to the top of the battery. What is this for? There appears to be a hole on the new (Interstate) battery, but it's ovular, not circular, like the M-B battery's. Do I need to connect a hose to this? I thought that this is a sealed battery, and therefore would not need anything to drain from it. Can someone shed some light on this?

[ajcrowe]

It is a vent for any fumes that may come off the battery. So yes you should connect the hose.

[Pete]

Thanks for the reply. However, according to the battery manufacturer, it is a "drainage" line for battery acid, in the (hopefully unlikely) event that the charging system malfunctions and overcharges the battery. In that case, the acid would drain, directed downward through the hose, rather than spewing out into some undesirable direction under the hood. According to the manufactruer, the battery has vents, but that's not what the hose is. This satisfies my intuition, as a footlong hose that hangs downward wouldn't be a good "vent". Does this sound correct?

In any case, whatever it is for, Interstate Battery has a warehouse that is only a few miles from my house, and they have the adaptor kit, which will allow me to hook up my OEM hose (round cross-section) to the ovular port on the battery. So, I plan to pick this up and install it, in the next couple of days. Thanks.

[ajcrowe]

I have not heard of a drain for acid. The only hose I have seen is the one on most batteries to vent any gas. Although it may be the same thing.