Was having a tiptoe through another forum today and found a thread that contains troubling info that may or may not be correct (you know what these forums are like!).
Allegedly the pre-Thor cars have a lower set point voltage on the alternator which is incompatible with calcium based batteries, resulting in them never charging completely and an early demise of aforementioned battery.
Anyone got any real-world experience or info on this? My MF31-1000 gives me a warm cuddly feeling whenever I open the bonnet, in the "one thing I don't have to worry about" region.
Now I am!

Hmm, not that I have a Calcium battery, or at least I don't think I have, but the alternator I got in France when mine died had the original LR label on it with the part number. That showed it to be the correct one for cars with a VIN up to TA so early cars. I wonder what the set point is on that? Although it's been on there for almost 5,000 miles, virtually all of it with the lights on (and the AC, a Peltier fridge and numerous other electrical odds n sods), and the battery hasn't gone flat yet

There were talks that the earlier Diesel models have an alternator with a voltage output of 13.8V, but the later ones then have a voltage of 14.1V
I'm not sure about the petrol models, but the resident know-it-all on LZ says the 'Thor' alternators were set at 14.5V (I don't think so as I see 14.1V at my battery when the engine is running!) so are fine with charging Calcium batteries.

I didn't have an issue with my '01, and a MF31-750 (well, it was a MF31-750 under the bonnet - now a 1000) AND a MF31-1000 in the boot. The MF31-750 lasted just over 4 years.

I think most car batteries these days have some calcium in them as it reduces bubbling and water usage, which is how they are all branded as 'Maintenance Free'. There is a LOT of debate, and contradicting information out on the www about it all. All I can suggest is that you check what voltage you are seeing at the battery terminals when charging, and if it's above 14V, then the battery will be getting a decent charge. Even if you need 14.4V minimum to 'fully' charge a calcium battery - it will be 'close enough' I think to keep the battery going for a few years. It was in my case, anyway.

If you are that worried about it, then you could always fit a battery conditioner to it when it's parked up to give it the extra boost to fully charge.

Orangebean wrote:

Was having a tiptoe through another forum today and found a thread that contains troubling info that may or may not be correct (you know what these forums are like!).
Allegedly the pre-Thor cars have a lower set point voltage on the alternator which is incompatible with calcium based batteries, resulting in them never charging completely and an early demise of aforementioned battery.
Anyone got any real-world experience or info on this? My MF31-1000 gives me a warm cuddly feeling whenever I open the bonnet, in the "one thing I don't have to worry about" region.
Now I am!

Hi,
I have a concern about my MF31-1000 battery because when the engine is running the alternator voltage is 14.3 volts. when you say "gives me a warm cuddly feeling" what voltage do you get with the engine running?

If the battery is fully charged, or close to it, that is fine. The very early alternators (up to 96 MY) had a set point of 13.9V, later ones are higher, around the 14.4-14.6V mark. Voltage will drop the closer the battery gets to fully charged so if you are measuring 14.3V that shows the set point is high enough and the battery is fully charged.

There is something in it though? People do tend to put in batteries without thinking about battery chemistry but different chemistry batteries do need different charging voltages and unless batteries get fully charged the effective amp-hour rating, cold cranking amps and life expectancy are all lower?

I suspect that back in 95-96, Calcium batteries didn't exist so the alternator set point was correct for basic Lead acid batteries. As battery technology moved on, so the alternators were changed to match the more modern batteries. It's much the same with anti-freeze. For GEMS the recommendation is Ethylene Glycol but for the Thor it's OAT. The engines are the same just OAT didn't exist when the GEMS cars first came out so the recommendation was what was current at the time. There is nothing to stop you using either anti-freeze in either engine (just as long as you don't try mixing them).