Testing batteries
 

I have 2 group 27 deepcycle batteries I took in for testing. @ 2 places. Continental brand batteries.

1st place input 450 CCA in the tester, both batteries tested good. ( I thought the 450 was to low of input, hense shop #2)

2nd place used 575 CCA input, now both checked bad. So I'm thinking both may be border line.
I mentioned the previous shop test, so they rechecked. Now 1 was good. :rolleyes: Then they rechecked at 450, both good.

Do I have no bad battery, 1 bad battery, 2 bad batteries, or 2 unqualified shops?

Re: Testing batteries
 

i always replace questionable batteries, it would suck to miss a weekend of boating over a lame battery

Re: Testing batteries
 

I think your right, they are borderline at best. If there remaining capacity is about 400-450 CCA, they will test good if tested as a 450 CCA battery, and bad if they are tested as a 575 CCA battery. Either way the batteries are weak and will fade fast at this point.

Merc recommends minimum 750CCA for a 502Mag MPI.

Dave

Re: Testing batteries
 

Thanks for reaffirming my thoughts Dave. Just wasn't sure if that's how they work, good at the lower rating, but bad at the higher.

Re: Testing batteries
 

junk them, the last thing u need is a battery problem -trust me.

Re: Testing batteries
 

The last thing you need is a blown engine and drive.

Bad battery would be at the top of my list of desired problems actually! :D

But in all seriousness, I agree that these sound like they are fading.

Re: Testing batteries
 

i'm w/you fund razor, bad batteries are at the top of my list for desirable mechanical problems -jeff

Re: Testing batteries
 

Update

charged both batteries for 2 days each @ 2 amps, and retested at 1st store, but had them use 700CCA. 1 Battery good, other required recharge and retest. I don't think so Tim, it was charged. So replaced it with a dual purpose battery with 1000CCA from AutoZone. Duracel (AutoZone) DieHards and many other are all made by the same maker: Johnson Controls. I 'think' JC also makes the Optimas????
If the other battery acts up this summer, I'll replace it with a starting battery.