Conversion from 2 6-volt batteries to 1 12-volt

[Sr_Pinguino]

Hi, I would like to convert my Austin Healey from two 6-volt batteries to one 12-volt battery.

If anyone has done this, then please let me know which battery was used and why. Also, did you have a tray custom made or buy one already manufactured.

Fyi, my Austin Healey has its original generator and also the original positive ground electrical system.

Thanks in advance. Sr. Pinguino.

 

[roscoe]

Many people would not do what I did, but I didn't want to spend hundreds of dollars for reproduction batteries when nobody but me will see them. So what I ended up doing was using 2 12 volt "lawn tractor" batteries, available for about 35 or 40 dollars at any auto parts store, wired them in parallel and voila! (or as some people say viola!). There are issues that may pop up when you charge batteries in parallel, in that they may not charge evenly and one may end up with a shorter life as a result, but I avoid that by swapping them around once or twice a year. I have plenty of cranking power and I know that no matter where I am I can go into a car parts or tractor supply store and get a replacement. I did make my own trays and hold-down brackets, using the attach points on the frame that were stock. They are the perfect size. One might do it, but I am glad I have two.

 

[AH100M]

Jon-

Sounds like a great idea. (Sorry for hijacking the thread but I'll give it back in a minute.)

When I first restored my BN2 back in the early '80s, VW 6V batteries were available in any auto parts store so it wasn't a cost issue. However when these disappeared I took my tape measure down to Sears and bought a 12V Diehard battery that would fit the space of one 6V. I'm not at home right now so I can't tell you the part number but the only dimension that proved to be a problem was its length (ie, front-to-back dimension when it's installed). So I had to remove one lip of the standard battery tray so that it would fit. Height, the most important dimension, was fine.

But now I'm going to try Jon's idea. I'm going to try to keep the stock trays and brackets.

 

[vette]

Hi Sr,

I own a '63 Healey 3000, BJ7. I have one 12v battery in the trunk mounted on the right hand side tucked tight into the inside of the rear fender. It is mounted on small angle brackets that have some plywood set across them for a base to set the battery on. It has a typical hold down arrangement that you would see on many cars. I am pretty sure that my arrangement is stock/original set up. I installed a group 27, 650 CCA battery in my car about 8 years ago and it and the charging system has been working fine. I also have a generator and a positive ground system. I did not know that some Healeys had 2 Six volt battery set ups. I had an MGA some years back that had 2 six volt batteries mounted in battery boxes behind the seats, but did not know that Healeys had them. anyway, a group 27 or even a group 24 battery with 550 to 650 CCA should do just fine.
Dave.

 

[Randy Forbes]

The 100s and the 100/6 & 3000 2-seaters all use a pair of 6-volt batteries.

I put a single 12-volt battery in mine probably 25-30 years ago, and never looked back.

I put it on the RH side to offset the car always being operated with a driver in the LH seat__so far, this too has worked just fine...

From memory, I'm thinking it's a Group 24 battery, but I've been wrong before. Currently fitted, is a sealed battery available from NAPA

 

[bighealeysource]

Like Randy said above, real simple to do and far less money than dealing with two 6 volt batteries. I cannot recall what size battery I used but it is one of the smaller stock sizes at places like Advanced Auto Parts,Auto Zone, etc. I also used a different battery pan but make sure it will clear your differential and if need be simply do an angle cut on the side that could be the problem. Your standard battery tie down rods will hold it in place.
REgards,
Mike

 

[Healeysince59]

I have a single Miata WestCo 12v battery in my BN1. Like Bill, I had to notch the tray on one side to get it to fit. It's small, light, has plenty of cranking power and, it's AGM technology. ( The replacement battery Miata dealers sell is a wet cell, not AGM)

Marv J

 

[John Turney]

I think several owners are using a single 12-volt Optima batteries on one of the trays.

 

[Sr_Pinguino]

Thanks everyone for your most interesting and valuable responses!

Sr. Pinguino