Flow-Rite battery watering system

[Snowman9000]

Just bought a 2014 golf cart that came with almost new batteries and Flow-Rite watering system. Since I didn't know the state of charge I went ahead and charged it. The battery tops looked squeaky clean before charging, but during charging I got a lot of fumes, and some electrolyte ended up on the tops of the batteries. From several caps, maybe all 6 batteries.

I checked the level after charging and they were not close to over filled. Looked to be less than 1/4 inch over the plates.

So how does this system vent? Somewhere on the caps, I have to assume. I looked at their site but didn't see anything on this. The tubes all look like new, the whole system does. But I don't want to have to contend with this mess after every charge.

As to the charge, it was definitely vigorous. I measured voltages. Suffice it to say it was doing absorption at the equivalent of 14.8v per 12v, at over 80 degrees F. They were definitely bubbling. (Club Car 48v using their PowerDrive3 charger.)

[Snowman9000]

I have decided some of the base gaskets are crapped out, causing the leaks. I called the company and they advised that since my caps were made in 2016, they were probably switched from the previous batteries to the new ones. He said they don't recommend doing that, because the failing batteries can mess up the caps. So the best practice is to buy a new system.
Since I can easily reach all the batteries to water them, I don't care too much about the system. So I ordered Water Miser caps to replace it.

[Snowman9000]

They are 8 volts.

[2oldman]

6-6v batteries should have a 36v charger, not a 48, unless they're 8v batteries.