p38 battery power

Datatek said:

Not really, it just makes sure you are less likely to flatten the doner battery. It's quite possible to jump start a vehicle using a spare battery, I do it all the time, I keep a large tractor battery on trickle charge for just that purpose. It does tractors mostly and my digger cos I'm too mean to buy a new battery for it.

Click to expand...

Haha nice, I jumped my boat engine with a spare live from the starter motor once when the remote ignition system packed up on the Thames! Closest I've come to hotwiring

Datatek said:

I did say "others". There are also several who have good experiences with them.

Click to expand...

I also had problem with one of these battery's

battery mega store did replace and so far replacements been good

jeff. said:

I also had problem with one of these battery's

battery mega store did replace and so far replacements been good

Click to expand...

Confirms really that they had a bad batch, the designation changed after I bought mine, I suspect they changed supplier and got burnt fingers

thanks for the replies folks

Datatek said:

Confirms really that they had a bad batch, the designation changed after I bought mine, I suspect they changed supplier and got burnt fingers

Click to expand...

Have known lots of new batteries fail over the years. Had a new Varta that failed, dropping a cell after three weeks, a year or so back. It happens.

I use a 115AH, 750CCA Alphaline from Battery Megastore in my P38 - replaced it when the one that was in it went dud the day after buying the P38... so far, so good though will be 2 years in Feb since I've installed it and still going strong. Starts the RR first go after having been sitting for 3 weeks whilst I'm away at work too.

And if that isn't enough, I've got a split-charge system with a 130AH (1000CCA) Alphaline (also from Battery Megastore) in the loadspace. Can be manually linked for boost starting - and I've got an 175A Anderson connector with 5m jump leads in the boot - so no need for opening bonnet if I need to jump someone..

Cheers,
Marty

well the new battery i got from battery megastore in oct is knackered had to get the rac out to get me home tonight its a 750cca and its only putting out 202 cca so rather peed of at the moment have sent them a email so will see what they do now

mutsnutz said:

well the new battery i got from battery megastore in oct is knackered had to get the rac out to get me home tonight its a 750cca and its only putting out 202 cca so rather peed of at the moment have sent them a email so will see what they do now

Click to expand...

Alternator OK? Too many short journeys to charge the battery?

RAC tested it with midtronic tester and the battery came back as goosed he said even if i put it on charge for 24 hours it still wouldn't give me the charge it needs to start the car supposed to be 750 cca from cold and it will only do 202 which is not enough to start a fiesta

mutsnutz said:

RAC tested it with midtronic tester and the battery came back as goosed he said even if i put it on charge for 24 hours it still wouldn't give me the charge it needs to start the car supposed to be 750 cca from cold and it will only do 202 which is not enough to start a fiesta

Click to expand...

Batteries will fail if not kept charged, you can't test the CCA on a flat battery. If the car stopped it was not the battery as the alternator provides the power when the car is running.

contacted battery megastore and they said i should fully charge the battery and get a battery test report done from kwickfit or halfauds and send it to them and if they deem its faulty i will get a replacement within 24 hours the car was running and starting fine had no probs with it and when i went to start it again wouldnt start it tried jump starting from a focus and no go it took rac jump starter plus a battery pack to get it to start

mutsnutz said:

contacted battery megastore and they said i should fully charge the battery and get a battery test report done from kwickfit or halfauds and send it to them and if they deem its faulty i will get a replacement within 24 hours the car was running and starting fine had no probs with it and when i went to start it again wouldnt start it tried jump starting from a focus and no go it took rac jump starter plus a battery pack to get it to start

Click to expand...

So, it sounds like it's not getting charged.

what should the alternator be putting in to the battery and i will test it once ive changed the battery back up

mutsnutz said:

what should the alternator be putting in to the battery and i will test it once ive changed the battery back up

Click to expand...

14.2 volts at 2K rpm after a couple of minutes max. Any less and the battery will be undercharged especially if you do a lot of short runs.

thanks data i will get onto it once the battery is charged up

Morning all,
we've been having a bit of bother with the battery power on the better half's discovery, (as I had on the P38 a few weeks ago.) Bitten the bullet this morning and ordered two 130 amp ones, as recommended by you learned folk, from Battery Megastore. That should sort it. My question is - what is the length of run needed to charge, or maintain a charge, in the battery? Obviously it uses a fair bit of 'reserve' to get started, and then there's lights, wipers etc etc, but how long do you need to drive for to charge it back up?

plumbfisher said:

Morning all,
we've been having a bit of bother with the battery power on the better half's discovery, (as I had on the P38 a few weeks ago.) Bitten the bullet this morning and ordered two 130 amp ones, as recommended by you learned folk, from Battery Megastore. That should sort it. My question is - what is the length of run needed to charge, or maintain a charge, in the battery? Obviously it uses a fair bit of 'reserve' to get started, and then there's lights, wipers etc etc, but how long do you need to drive for to charge it back up?

Click to expand...

In practice it is very difficult to recharge a flat battery by driving. starting a car is a very high draw but for a very short time if is all in order, so in amp hour terms not a lot. Lights & wipers etc do not use the battery when you are driving except perhaps at idle, they are powered by the alternator.
If the battery is flat you need to use a charger, same if you do a lot of short runs.

I've realized through recent experience that there are all sorts of strange effects on the P38 from having a weak battery. The much discussed key fob problems, strange fault messages, let alone the obvious starting, can all be sorted by having a fully charged up battery. That's one of the reasons why I'm getting the 130 amp one - it removes a hell of a lot of doubt. At my age I'm all for a stress free life ... (so why did I get a P38 ?!)

How about to maintain the (fully) charged battery? Presumably lots of short runs will eventually discharge it, so what do you need to do to maintain it?

If you have a calcium battery fitted and a standard 14.2 volt regulator the battery will never get fully charged. Calcium batteries need 14.4 volts to reach full potential.