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MG MGA - Battery life query

I have two 6v batteries fitted to my roadster that were installed in 2007. They still work fine. Car averages around 30 days use a year and say 12 starts a day when in use. In 2015 I plan to take the car to the UK and Europe for a couple of months touring around - do I need to replace before I go or would using a Ctek type maintainer keep them in good condition? Why do batteries fail and can it be prevented?
Mike
Mike Ellsmore

Just an aside - a friend of mine who ran an acid plant years ago would drain his batteries every couple of years and then top up with new acid solution. He reckoned his batteries would last forever by cleaning out the lead sulphate deposits!
Mike
Mike Ellsmore

Mike, I keep trickle chargers on my cars (including veterans) to try to keep the batteries going. They have gone up in price in recent years but probably still worth the trouble!
Barry Bahnisch

I'm guessing 7 years is pushing your luck with 6-volt batteries. I could never get more them 4 years out of them in regular use, and the things are particularly expensive. I switched to a single 12-volt battery about 1994 with no regrets.

I installed an alternator in January '07. My most recent 12v battery replacement was in August '07, and that battery is still doing well 6-1/2 years later even in cold weather.
Barney Gaylord

I have bought more of those old technology 6volt batteries than you can shake a stick at. Some lasted no time at all.
I suspect that yours have lasted so well because ...
# Your voltage regulator is adjusted precisely; the maximum charging voltage (and therefore charging current) are as specified by Mr Joseph Lucas. (Extended time at high charging current kills batteries).
# You probably don't need to continuously run the electrical system 'flat out' (headlights, heater, wipers going for weeks. I assume you've not got aircon... :o)
# Your batteries probably haven't been left out in -20C when nearly discharged (frozen electrolyte is another good way to kill a battery)
# Oh yes, I lost another pair of batteries when the car was under a metre of water for a couple of weeks.

I've made all those mistakes in the past. A couple of years ago I bought a new tech calcium battery, reset the voltage regulator. Should have done it years ago. It's easy to do (and to revert to 2x6v).

You'll enjoy it here but don't come between November and April!

Yours
David
D Brown

Mike, I have fitted a single 12v battery to my car, it is probably a little bit undersized for my 1900 MGB engine but it has worked ok so far for about 5 years.

I use the car once or twice a week in the summer for short journeys but in the winter it is pretty much in storage with a cheap ALDI battery conditioner connected to it.
Im hoping to get at least another year out of it.

When the time comes for you to replace your batteries may wish to try Steve Gyles system of fitting two 12v batteries wired in parallel(I think). You would get brilliant starting power,save a lot of money, get better battery life and keep the car looking almost original.

Colyn
c firth

Gents. In my humble opinion a single 12 volt battery is quite sufficient and works really well on my Twin Cam. It has ample cranking Amps capability and, unless you need masses of Ampere Hour capacity for parking for hours with lights left on - our cars are probably too cherished and prone to theft for that to be a good idea - then the single battery is fine. It also leaves the other battery tray available for keeping bits and pieces stored out of sight. But, the bottom line is you don't need two 12 volt batteries to reliably start your car, even in adverse weather conditions. You also minimise the potential for more cable connection problems with just one battery. Just one suggestion - the most common starting problem area is the battery earth connection to the chassis of the car. It is well worth the effort to run a dedicated battery cable from the existing battery-to-chassis connection point all the way forward to one of the starter motor mounting bolts. No more earthing problems!
Bruce
Bruce Mayo

Bruce
I totally agree.
Once I had done that, starter performance was transformed - better than any time since I bought the car in 1970.
David
D Brown

Colyn

I have reverted to just the one battery now. I have my doubts about the overall battery lives when I had the two. I operated them alternatively (every day or two) but I have come to the conclusion that it is perhaps better to have one battery being worked hard continuously than two working at half pace. Yes, I had them in parallel and each independently isolated.

I only went down the dual 12v route as I had a spare good battery in the garage and thought it might be more useful in the car than on the floor.

Steve
Steve Gyles

Being partial to the original look of the 2 six volts, but put off by having to replace them anytime soon at their price, I checked around and found these guys: http://batteryminders.com/
I got their model 12117 & have been using it for the past couple years. I also got one for my regular car. It keeps the battery(s) charged w/out overcharging (you can keep it plugged in for weeks, months..) What compelled me to get it though, is that it addresses the sulphation build-up in the battery that can lead to early failure. Peruse their site for details.
Rick deOlazarra

Being partial to the original look of the 2 six volts, but put off by having to replace them anytime soon at their price, I checked around and found these guys: http://batteryminders.com/
I got their model 12117 & have been using it for the past couple years. I also got one for my regular car. It keeps the battery(s) charged w/out overcharging (you can keep it plugged in for weeks, months..) What compelled me to get it though, is that it addresses the sulphation build-up in the battery that can lead to early failure. Peruse their site for details.
Rick deOlazarra

I just left the lights on my 6v farmall cub tractor. Had to remove battery cover to charge it and just happened to see I bought it in '06. I only use it for snowplowing and never charge it during the summer. Just a regular 6v from our local farm store,Farm&Fleet. I also still have a 2000 Motorcraft 12v battery from my Dads old Town Car that I use in a boat. That one I keep on a Schumacher maintainer,I'm to the point that I just want to see how long it will last. It does have two batteries so I don't worry about it starting. I retired a couple of years ago from AT&T,we had over 100 vehicles in one garage. They tried going cheap and I alone went thru 3 batteries in a month in a 8.2L Chevy.Our mechanic started putting Motorcrafts in everything and the problems went away.
gary starr

This thread was discussed between 07/02/2014 and 09/02/2014

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