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Odyssey or try a Varta.

Expect over ten years life.

I had a BL Unipart battery on my MGB - guaranteed as long as you keep your car. They didn't figure 22 years and after about six batteries, they stopped the deal.


DaveW
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Originally Posted by Peter J
Update:

I disconnected the battery, so no connection to the car. After 36 hours in "Recovery Mode" on the Ring Charger It will not go above 60% charge.
So my conclusion is that the battery has developed a fault.
Back to Halfords. The only battery they stock that fits the Plus 8 is the one I have: there are no other options. I paid £71.00 in April 2019, it was replaced for the same reason a year ago.
Third time lucky?

Or should I cut my losses and get a substitute: because of the way the battery is fitted in the Aero Plus 8 there are limitations on size, in particular the Optima Red Top is too long: the maximum is 242mm, the red top is 254. The best candidate seems to be an Odyssey model.


So the battery is cream crackered although not surprising considering its open circuit voltage dropped to six! Although lead/acid batteries don't have a memory per se there is a scenario where they are regularly re-charged to only say 90% and they end up with 90% of 90% capacity and so forth in a downward spiral.

My own view is that a good brand such as Varta suggested by DaveW, will last for many years if treated well, but so will many others, again if treated well. Very expensive exotic brands may last longer still but in so doing leave you with marginal capacity for longer towards their inevitable and extended end of life.

"Treating well" means using regularly with an easy starting engine, and journeys long enough to fully re-charge. Not flattening whilst attempting to start a faulty engine. Being left permanently on smart charger/conditioner when not in use for more than a couple of weeks commensurate with re-cycling charger every two to three weeks if it doesn't do this automatically.

Pointless doing any further tests until you have a new replacement, but important to determine the level of static drain and reduce/eradicate once you have determined what's causing it. FWIW I would be tempted to stick with a new Halford's one whilst you sort the issue.


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If you can get your money back a swap might be better. I have Halfords worked fine . So maybe 3rd time lucky.


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Not sure if this relevant, but on the disco3 forum that I frequent from time to time, there was a thread on batteries. The original L-R item seems to last 7-9 years (my disco 4 is just 8 years old and still on the original). Halfords batteries last a lot less than half that time in the Disco.


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Peter J Offline OP
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Halfords changed the battery without any discussion. Well Done Halfords!

Installing the battery I connected an ammeter between the negative pole and the ground cable.
1.2A with the ignition off.
Clearly something is wrong... it was associated with what sounded like a relay cycling inside the electronics box.
I think this is something for an auto electrician, it is beyond me....!

For now, I'll leave the car connected to the charger....


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Hunting around, consensus seems to be that anything in excess of 50mA is too much.
Good luck with finding the fault.


Paul
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Originally Posted by Peter J
Halfords changed the battery without any discussion. Well Done Halfords!

Installing the battery I connected an ammeter between the negative pole and the ground cable.
1.2A with the ignition off.
Clearly something is wrong... it was associated with what sounded like a relay cycling inside the electronics box.
I think this is something for an auto electrician, it is beyond me....!

For now, I'll leave the car connected to the charger....

Good call Peter, with both confirming an excessive discharge and Halfords service. 48 hours with that discharge, assuming constant, would have a Mog sized, new fully charged battery completly flat within 48 hours! It definately needs attending to a.s.a.p. if only because that amount of energy is being dissipated, probably locally, as heat!

Suggest popping that 150 amp breaker in the meantime when not in use.


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Peter J Offline OP
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Originally Posted by Richard Wood
Originally Posted by Peter J
Halfords changed the battery without any discussion. Well Done Halfords!

Installing the battery I connected an ammeter between the negative pole and the ground cable.
1.2A with the ignition off.
Clearly something is wrong... it was associated with what sounded like a relay cycling inside the electronics box.
I think this is something for an auto electrician, it is beyond me....!

For now, I'll leave the car connected to the charger....

Good call Peter, with both confirming an excessive discharge and Halfords service. 48 hours with that discharge, assuming constant, would have a Mog sized, new fully charged battery completely flat within 48 hours! It definitely needs attending to a.s.a.p. if only because that amount of energy is being dissipated, probably locally, as heat!

Suggest popping that 150 amp breaker in the meantime when not in use.


Richard,
I did that, but the drain is still there and the relay cycling sound didn't go away, which is why I took both connections off the battery and tried to recover it.
Talking to Tony at Williams he said that the Aeros with the 4.8L motor all draw about 500mA with the ignition off, so something isn't right.

Anyway, the car is connected to a Ring Charger on "maintenance mode", I don't want to damage this battery.

Peter


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Originally Posted by Peter J
Talking to Tony at Williams he said that the Aeros with the 4.8L motor all draw about 500mA with the ignition off, so something isn't right.



Even half an amp sounds like an awful lot to me, do the equivalent BMW cars with the same engine do the same, or is it something MMC have done that causes it?


Tim H.
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Originally Posted by Peter J
Halfords changed the battery without any discussion. Well Done Halfords!

Installing the battery I connected an ammeter between the negative pole and the ground cable.
1.2A with the ignition off.
Clearly something is wrong... it was associated with what sounded like a relay cycling inside the electronics box.
I think this is something for an auto electrician, it is beyond me....!

For now, I'll leave the car connected to the charger....

Was that immediately after switching the car off? It can take some time for various modules like the ECU to power off. Are you positive there isn't a tracker fitted? My son's car had had a black box fitted and not removed by a previous owner. When its internal battery ran out it drew off the main battery and drained it after a few days.


1972 4/4 2 Seater
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