Battery Leaking - 4th Replacement
 

Has anyone experienced battery leaking issues with the BRZ? I have had my battery replaced under warranty 4 times now and the issue occurred again after less than 8 months.

Each time I have gotten a replacement OEM subaru battery. I am now concerned with the leak effecting rust in the engine bay.

No, not on my 2013 FR-S.

Where is the battery leaking? Out the fill places? Around the posts? From a crack in the case?

Is the battery secured properly?

It could be that the battery is overfilled.

It could be that the alternator is overcharging it, causing it to boil over.


humfrz

With that many replacements it is likely an undiagnosed issue with the car itself IMO.

Overcharging? Have them check the charging voltage.

And yes due multiple cleanings with baking soda and lots of water!!!!!!

Have the alternator tested. Not just voltage and amperage, get a full charging system check

Leak in the same spot ? Something rubbing it ? Gotta find the source the leak and see if it is common and if it is what could be causing it.

22R

I bet that they were all damaged by the guy who installed them. The seal between the soft lead posts and case are extremely vulnerable. Few people consider that when tightening the connectors.

If it is a crack then mounting or bad install.
If out of the cap vent then over charging.
After four times I would thing you would want to know where the leak is coming from.
After four times I would think the dealer would look at the battery carefully.

What is a "full charging system check"?

Thanks for the responses guys. Here are some pics of the battery. The leak seems to be coming from the two fill ports. Also the negative post has a bluish hue and also seems to be leaking. The rust is an accumulation of the 4 batteries failing on me.

The alternator overcharging could be a good guess as to what is causing this. What type of test can be done to check on this?


https://i.ibb.co/yYVHzH2/IMG-1535.jpg
https://i.ibb.co/vPnxv4g/IMG-1536.jpg

Put a volt meter on it while idling and see if it is close to 14V. If you can hook up a scan tool or gauge to the ODDB2 port and read the Volts while driving to see if it exceeds 14V

22R

If it is coming out the vents it is the probaby from overcharging. If you have a volt meter put it on the battery when running. You are looking for around 13.8 to 14.2 volts. It should be stable even at high rpm’s. Everything needs to be cleaned with baking soda and lots of water.

Just got a multimeter on it. With the car idling(no auxiliaries). It showed 14.4 volts consistently which is around normal voltage.

I'll try to get my OBD reader and measure voltage during a drive cycle. Could be overcharging then. I'll report back with my findings.

Yeah that's overcharge.

A voltmeter will show voltage, but you need to see ripple, loaded voltage and amperage too. He needs a real tester, not a voltmeter.

I was asking because voltage and amperage are the only metric to test an alternator by.

"Loaded" is the only way to test an alternator, as sticking multimeter probes on the battery terminals at idle with all accessories off isn't an alternator test. He can easily do it all with a cheap meter. VAC on the alt case and B+ terminal will show ripple better than the usual "charging system tester" with a ripple/diode indicator. But a leaking battery isn't likely to be a ripple issue. You don't need an amp clam, all accessories and lights on and a 1500 RPM idle is all the load you need, observing an output voltage that remains comfortably around 14V is all you need to know to confirm amperage output.

What we want to know here however is if the system is over charging, and we'll find that out by turning all the accessories off and having the engine turning at usual driving speed. It's OK to do this parked, and an overcharging alternator will simply show up as gradually increasing voltage following engine RPM, steadily increasing over 15 and possibly over 16V.

Is your car tracked or auto-crossed?


Mine was always fine durint street use, but would notice it to be a tish wet after tracking/autox events.

Possibly (likely) culprit is a faulty voltage regulator. A fellow racer had his battery spew it's guts all over his engine bay twice until we finally put a volt meter on the terminals and revved the engine a bit. The Voltage regulator should keep the voltage at a constant despite RPM like RZNT4R mentioned. However his would climb with RPM - 12v @ idle and I believe it jumped to 40v or more over 3000rpm.



On his car the voltage regulator is inside the Alternator (not sure on our cars) so swapping the alternator, along with cleaning the engine bay with baking soda, and we were back on track.

I installed a Shorai battery in September of 2014 and I've had no major issues. I have noticed the battery doesn't like cold (sub 40s F.) but it still starts first try.

There was an old thread (locked now) where a forum member was selling custom battery trays to accommodate it and I picked one up. Definitely recommend running Shorai, I've been very happy with their products.

I removed the factory style and went to a 11lb Braille unit. Made my own install kit as I wasn't going to pay 100ish for the FT86SF unit.

Nice, any issues? When it gets cold I think the longest I can go without driving my car is about 8 days. However I picked up the Shorai charging unit so if it goes longer I just hook that up.

I have a CTEK charger wired into the car, its not a daily and is stored in winter.

I had a little trouble starting the last autocross I was at when I took it off the trailer and in the morning for the 2nd day. It was 34 degrees and I am on a E85 OFT map with no adjustments to cold start tables. I did have some cold start issues on really cold mornings with previous battery as well.

Hi, sorry for resurrecting a kinda old thread... But has anyone found the issue yet?

I've had the battery of my 2013 BRZ leak twice within the passed 3 months. Had the first battery replaced under warrany after it leaked during autocross and when I had it checked with those fancy tools you clamp onto the battery, I was told the charging system was fine...

The replacement I got leaked 3 months after out the vent hole during a trackday. (Maintenance free battery)

While on the track I plugged in an obd2 reader and was monitoring voltage during a track and if I remember correctly, it never went above 14.5 or (14.2 I think) which is supposedly normal. Had my eyes on the track.
It seems to only happen at high rpm high load scenarios as it didn't leak on the way home from the track, but would always leak when I would go out for a lap on the track... I taped a piece of tissue over the vent hole to confirm that the battery was leaking out of there.

Now I'm thinking if this is still an issue with the alternator even after having it checked and nothing is wrong, OR it is the sensor with the plug on the Negative battery terminal as it is supposed to monitor the battery (?). I'm not completely sure, but I'm stumped right now. :( not sure also if it's the brand of battery I'm using or if I got a bad battery? But c'mon 2x within 3 months!?! 😪

It's the second time I will be having to clean and paint my engine bay because of the battery fluids leaking and rusting out the car :/

Anyone have an idea what may be wrong?