Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Determining the age of the battery

Hi All,
I have just purchased my first Morgan - a 2014 Plus 4. How long do the batteries last for on average and how do you determine the age of the existing battery? The markings on the battery seem to indicate Nov 2017 i.e. the number 11 and 2017 have x's on them. Is that the age of the battery or the recharge/ replace ?

Congratulations and welcome to the forum.

The battery on my 1999 Plus 8 is eight years old now and still spins the engine over effortlessly, never been on a battery charger but I do have a battery Isolator switch which I throw when leaving her without a run for over a week.

The newer models have a lot more alarm/electronic gizmoes and a few people leave them plumbed into an intelligent trickle charger, having worked in electronics my whole life I am not a fan of this practise.

I'm sure you have answered your second question.

Enjoy your miles and don't lock it away in winter if there is no salt around. some of my very best runs have been in winter in light snow on Dartmoor when only the farmers are about.

Either buy or borrow a battery tester. Your local garage will have one. If you are in East Suffolk you can borrow mine

Age isn't necessarily an indicator of health.

More details here

Hi Richard,
Where have you fitted the battery isolator switch and what make is it?

Thank John - a very useful link.

Hi Bob, mine came fitted but it's behind the drivers seat fitted to the vertical saddle board just above the battery and it is identical to this one.

The ECU leaves a little of it's running data on restoration of power but within a few miles it is back up to speed monitoring your habits online as it were.

Interesting that the content provider of the oft quoted GoMoG`s much valued Morgan related website, is seemingly not welcomed to post on TM by some here...

I have found that some battery`s have the week/year date code stamped on top of their negative terminal.

As Richard suggests, over the years such has been the "advance" in terms of on board digital electronics, that we may have moved on from the possibility off just disconnecting and reconnecting of a vehicles battery causing the ECU to adopt a limp/get you home mode, whereby more modern vehicles can throw up all sorts of fault codes to scare one to death...!!! Thus while a battery isolation switch might still be a good idea....????

The service life of the battery could also depend on the Morgan model. I am not familiar with the Plus 4. In my various Roadsters, the battery was drained after three weeks. I sometimes forgot to use the main battery switch and disconnect the battery. As a result, the battery was often deeply discharged and the service life was only one or two years. My 4/4 has had its first battery for 10 years and 120,000 km. So a lot of starts etc. I never use the main battery switch, because in the 4/4 I can start the car after three months and no consumer sucks noticeably on the battery although I also have an immobilizer.

Hi Bob and welcome to the forum. Regarding starter batteries remember they are consumables. I wouldn't be too concerned with age either since it's possible to ruin a typical lead/acid battery in a matter of months if it's not charged adequately on a regular basis.

Another point is that Morgan cars are often used sparingly and/or laid up during the winter months. Leaving the battery on a smart multi-stage charger in such situations offsets their degradation due to loss of capacity but is still not optimal.

Batteries thrive on being used so an easy starting car used regularly throughout the year will provide the greatest longevity. Six to eight years is a typical span for one well looked after. Some claim as much as twelve years but that's nothing to be proud of, it simply means you're sailing closer to the inevitable day there is insufficient capacity to turn over the engine, typically when winter temperatures strike.

Measuring the voltage across the battery a few hours after use gives a good indication of its state of charge (SOC) but since this is only within the confines of remaining capacity, it's not always that helpful.

Most Morgan's should survive three weeks at least without charging. If in doubt though leave it on a smart charger with float mode if it's going to be unused for longer. This in preference to those who use a battery kill switch. Modern cars have adaptive mapping within the ECU and this will lost with battery disconnected so the engine will have to re-learn which may take some time to optimise. Car radio's loose station memory similarly.

Finally please stay clear of old style "battery testers" since they put a brutal load on the battery which may achieve little more than finish it off and at best may take a chunk out of its life.

The battery on my 2013 lasted 7 years and then threw in the towel, the battery on my Fiesta ST is 9 years old so who knows.