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What size Battery for a AH BJ7 neg grd

Johnny

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A friend of mine recently asked me what size battery do I have in my car as he needs a new battery. Upon looking at mine I realized I too probably should get a new battery as well. I bought mine from Walmart in August of '07. It's an EVERSTART part # 58R3, with CCA of 580 and CA at 690. I'm using a generator so I don't need a large battery, plus I use a trickle charge occasionally (not good to leave on all the time). I've heard the new Optima battery's are good to use because they are gel filled not acid type. However at $200 plus it's kind of pricey for a battery.

The size of battery should be group 22, correct?

So, what are you using?
 
A group 42 with 675 CCA Min
 
Thanks Keoke......

I've heard there is available a "tar-top" battery that is gel filled. Anybody own such a battery? If so, where can you buy one?
 
I've heard there is available a "tar-top" battery that is gel filled. Anybody own such a battery? If so, where can you buy one? Yes there is, it might be the Odesey line ????
 
I don't see a tar-top battery by Odyssey. Odyssey and Optima are both AGM type, which is not gel. Gel type batteries require a different charging voltage for best results. Either an AGM or wet cell is satisfactory for a 3000. I have one from Costco which works fine.
 
Hi, I've had good luck with a group 27 in the Healeys with the battery in the boot. It fits the original tray and mounting bracket correctly and the posts are on the opposite side from the bracket, avoiding any shorts. If you have converted to neg. ground, go for the 27f which switches the position of the posts. I'm using Bosch, available at Pep Boys, and I see Advance Auto Parts has Auto Craft brand. So far the two I'm using are 6 and 7 years old with no problems. Bob
 
Thanks John, BN4. What do you mean by different charging voltage?

Other than by changing to an alternator how can you change the charging voltage using a generator?

I know you have to be careful and not buy a battery too large or the generator won't be able to keep it charged.
 
Thanks Bob, I'm a little confused here. I always thought it would be better to have the posts face towards the center of the boot, rather than next to the rear fender where it's difficult to get a wrench.

Also, isn't a "27f" battery larger than a "24"?
 
Johnny, The 27 and 27f are larger than the 24, but fit the bakelite tray and fit the metal hold-down bracket correctly. Having the posts away from the metal bracket prevents the bracket from shorting out across the posts if it should loosen. If you're not using the metal bracket, putting the posts more toward center would make it easier to use jumper cables. The BJ8 had a thicker wooden spacer on the inner fender that put the battery more into the boot area, with the tray on the fuel tank a little. The Bosch runs about $100. and the label peels right off if you like a plain black battery. Good luck, Bob
 
I believe BJ8s--and possibly other models--were designed for a battery that had a horizontal notch on the side, where the wooden standoff would fit (kind of a 'tongue-and-groove' setup). Since those batteries aren't available any more--I did see them advertised once many moons ago--I trimmed my BJ8's wooden standoff lengthwise so the battery wouldn't take so much of the (limited) boot space. Also, the battery remains more centered vertically over the metal brace below the bakelite tray.
 
Johnny said:
Thanks Bob, I'm a little confused here. I always thought it would be better to have the posts face towards the center of the boot, rather than next to the rear fender where it's difficult to get a wrench.
No
Imop this orentation IS preferable too.This minimises the potentil for shorting the battery when loading the boot and prevents acid damage to articles placed in there. .

Also, isn't a "27f" battery larger than a "24"?
 
The earlier BN4's and four-seat 3000's also have the wooden spacer along the inner fender. My battery has the posts toward the center of the trunk, and the top of the battery is covered by a vinyl cover, as standard, that provides some insulation against shorts.

As to the charging voltage of gel batteries, the ideal charging voltage is about 0.5 volts less than wet or AGM batteries. Gel batteries are not usually used for starting batteries, but if they are overcharged, bubbles form in the gel, reducing their capacity. If AGM batteries are overcharged, the can lose moisture and capacity, but they are not as sensitive as gel.
 
Sorry to resurrect a past "post" but I finally decided on the group 27 battery for my AH BJ7. Thanks to you Bob, I agree it fits the tray nicely and seems more than adequate.
I paid $91 at Sam's Club for a Energizer battery with a 3 yr and 8 yr prorated warranty. The cover is from Moss, plus I lined the inside with an absorbant material in case I get a leaky cap.

Thanks to all who responded.
 

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Looks good. Did you by-pass the on-off switch for a reason? Looks like you went right to ground. There's a Bakelite tray available that offers a good support and containment. Bob
 
Thanks Bob, I did bypass the switch to avoid any future problems. The switch is working but it's almost 50 yrs old so I decided to re-route the ground cable to avoid possible trouble.
 
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