Possible Voltage Regulator or Battery Failure

[AustinWash]

I have a 2000 Ford Explorer Limited I'm working on and I'm trying to figure out whether I need to get a new battery, a new alternator, or just a new voltage regulator. The battery before starting reads a decent 12 volts, but reads 14.6 or so once running, which seems a bit to high. Occasionally when it's cold in the mornings once I'm done driving it someplace, I can see the battery producing a bit of "venting", which is fairly dumb to ignore. The vehicle performs normally otherwise.

Anyway, I'm just wondering whether it would be idiotic to start by replacing the battery. It's clearly not got a dead cell as the reason it might be receiving too much charge from the alternator, but it is an exceptionally old battery, and it probably couldn't hurt to replace it anyway. My only concern is whether I might fry a new battery if what I'm looking at is a mild voltage regulator failure or alternator failure. Any thoughts?

Thanks for the input!

 

[BrooklynBay]

14.6 volts for a cold charging system is fine. Is it the same voltage once it warms up or does it drop? It usually drops a half to a whole volt once it's warm.

 

[AustinWash]

Interesting, because I measured it once I ran it for a while and it wasn't terribly different, 14 or in that area. I'll measure it again today but the fact is that I've not gotten a warning about voltage on the dash and it still runs normally. I guess now I'm wondering whether a battery can just start venting without it being because of a dead cell, even while the alternator and voltage regulation are working fine. I have had this battery for a seriously above average amount of time but it still holds 12 and still functions, so it took me a while to notice any issue.

 

[BrooklynBay]

Does your regulator have a large aluminum heatsink? That model doesn't reduce its voltage when it warms up as much as the regular model without the heatsink.

 

[AustinWash]

Does your regulator have a large aluminum heatsink? That model doesn't reduce its voltage when it warms up as much as the regular model without the heatsink.

I think its the alternator model with the internal regulator, which has a heatsink I think? In either case I tested the regulator again today by giving it some gas and it actually seems to work fine, doesn't climb above 14.6 or so. So I'm supposing its just the battery now. It might be worth trying to top off the distilled water in the cells?

 

[BrooklynBay]

Any auto parts store could test the battery for you.