Car is making batteries leak... how & why?
 

I had a basic DieHard battery that was a year or two old. Noticed it had leaked - heavily - and was basically sitting in a puddle in the battery tray. I cleaned up, replaced the battery with a new DieHard, and proceeded to do a track day today with the new battery. Sure enough, by the last session it was visibly leaking again.

Possible causes? I've got 13.8-14.1v showing on the PFC commander, which seems normalish. Could I be overcharging the battery at high rpms on track? Too hot in the engine bay? The car's barely been driven since last November except for three track days in cool weather. Or is it something else? Short somewhere or something?

Thanks for any help. I'm in the dark and googling hasn't gotten me too far yet.

Voltage sounds normal.

I had to switch to an AGM battery as a result of acid spilling while going around turns(autocross)

Are you over-tightening the tie down? Any large electrical draws? Stock alternator?

IIRC the alternator has a switch built in to prevent overcharging, could be gone or failing on yours....
Hopefully some others have good ideas.

I thought about the tightness thing so i just screwed down the new one to the min where it wouldnt move with a mild shove. I don't think it's overtight.

Not much draw. Three guages and a PFC, but stereo is deleted.

Stock alternator.

Hmm.

K-Tune, that's really interesting. I was pushing hard for entire 25min sessions bc the car loved the cold air temps. Grippy street tires (RE71Rs). Wonder if it literally splashed out. Hmm. Anyone else have that issue?

high electrolyte level and poor vented caps, sometimes you can't avoid it.

Yep, that's what I'm thinking as well. The battery caps aren't sealed so you're sloshing the fluid around in the battery and it's leaking out the caps on the top.

I don't see anything wrong with the charging system. Go to a sealed battery or see if there's a better regular battery out there.

Dale

Wow. What's the easiest/cheapest way to put a smaller AGM or Li battery in the stock location without a bunch of rewiring? I was planning on relocating soon anyway, but I've got another track day in a week!

I have never had this problem with an Interstate battery. Been using them for decades.

Buy Optima Red Top -> Remove old battery -> Put new battery in.

On left handers I was able to get acid to come out of the vents. You can see it on the intercooler...but it also got on the IC bracket, pulleys, catch can and IC couplers. I now run a group 51 yellow optima in a turbojeff tray.

Attachment 604607

Drycell is the way to go.

K-Tune, that battery is IDENTICAL to my diehard. Must be a rebrand. Same rounded rectangular vent and brackets for the handle. Maybe that design is just prone to it for some reason.

That battery is made at the Johnson Control factory, and they supply a bunch of other "brands". So it's likely the same battery with the same problem. It probably wasn't designed with near or over 1G lateral in mind.