VN Keeps Killing Batteries?

[DarrenF]

First post here so hello from ACT!

I think I'm having an issue with my VN killing batteries. I'm on my 3rd battery this year. I thought the first one failed because it was old. When the second one failed I took it back to Supercheap and was given a voucher refund. The first battery was a Yuasa. The second one was a Century battery. My current battery which just died is an Exide battery.

It seems really unlikely that I'm getting faulty battery after faulty battery. Is there something else I should be checking to determine if my car is killing batteries? Alternator output and battery voltage seems normal until they're randomly dead.

This car has been good to me otherwise, reasonably reliable and lots of fun!

Thanks!

 

[strgas]

any extra power requirement's on the car or added extras to load up the electrics ?

possible the alternator is over charging and cooking batteries , poor earth return circuit or lead to engine block may lead to voltage spikes from the alternator ?????

 

[DarrenF]

There's no aftermarket stereo or lights or anything. I've been keeping an eye on alternator voltage output and it seems to sit around 14.2 volts.

 

[hakhawk]

14.2volts when? at idle? at higher rpm? with lights/aircon/other elec loads on?

 

[DarrenF]

It doesn't fluctuate much from 14.2 volts. Idle, limiter bashing it, highway cruising etc.

 

[Immortality]

14.2 volts seems good. Where are you measuring this?

What size battery?

 

[AdventraAddict]

Check the wire from Alternator to battery for damage and corrosion, Use a multimeter to check resistance from alternator lug to battery positive, Common issue to get slight overcharging due to over excited alternator usually caused by this..

 

[HarryHoudini]

I had 2 Exides die on me but my VN wagon isn't used much,i purchased the first one at K-Mart as i had some return vouchers,expensive top of the line one,lasted less than a year but K-mart surprisingly gave me another one,that lasted just over a year and a cell collapsed whilst at my Brothers place in Sydney,purchased a NRMA one and so far its lasted 5+ years.
I was the same as you starting to look for potential faults after the second one but it was the battery,Exide must have produced a bad batch where the cells weren't seated properly.
Anyway not saying that your problem,but the batteries themselves were mine.

 

[DarrenF]

I was measuring 14.2 volts from the alternator. I haven't seen the batteries over 13.5 volts. There's no corrosion surprisingly. What should resistance be on the wire between alternator lug and battery positive? I'm guessing it's okay since the batteries haven't been over 13.5 volts that I've seen. Thanks everyone.

 

[strgas]

.7 of a volt difference should be less than .2 of a volt .
quick check is jumper cable from alternator lug to battery and remeasure voltage at battery no change then try jumper cable on engine earth point and battery negative recheck battery .

14.20 at alt should see 14.00 at battery aleast .