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MG Midget and Sprite Technical - Discharged Battery

I've done it again, left the trickle charger off too long (I don't like leaving it on permanently) now the battery is too low to accept trickle or normal charger.
I think it may be sulphated? Is their a way to recover or do I need to bite the bullet and fit a new one? I guess its the clock that drains it.
Colin
C Martin

Do you have a smart charger? Or even a "dumb" charger - I'd try charging it anyway, you've nothing to lose.
Most garages can put it on a battery tester for you, but it needs charging first.
My wee 8amp smart charger was only about twenty quid or so and it's been a godsend. Worth every penny for the batteries it's rescued. Right now it's aboard my mate's RIB.
I'd give it a go Colin, before buying one.
Greybeard

ETA: Grey posted whilst I was typing - 8 amp is big compared to my old 4 amp which I use in conjunction with my Accumate battery conditioner to rescue and recharge neighbours' cars.

Colin,
it depends what you mean by trickle charger, given long enough, possibly a few days, with all being clean and in good condition the battery should pick up again. You want to use the trickle charger, not faster and more powerful battery charger, for a couple of days (as the modern battery chargers don't work on battery in a very low state of charge).

The discharge was low and long, the recharge wants to be low and long.

You could try Granville Bat-Aid Battery Aid Tablets and/or a battery conditioner charger (like, for example only, Accumate 6v/12v Battery Conditioner).

It's important to have the battery and all connections clean, secure (and protected) this includes battery posts, battery clamps, other connections and earths to get the full charge and prevent discharge.

Of course driving the car more regularly over reasonable length journeys will help the battery and rest of electrical items used and/or tested - plus the tyres, brakes, steering, suspension even the very less important components like engine, carbs, gearbox, rear axle, ect..

You can leave a battery conditioner on all the time, it cycles itself as required.
Nigel Atkins

A lot of the cheap modern "smart" chargers won't do anything if the battery voltage goes below a certain voltage.
Rob
MG Moneypit

Rob's right - most modern chargers need to sense a minimum voltage before they'll switch on. You can fool them by connecting another battery in parallel long enough to get the charger going. Use jump leads. Once it's up and running it should just get on with it.
Greybeard

Most modern chargers are too clever for their own good.

I have success in reviving batteries that have stood for years by putting them on my starter charger on "start" for a while until they start to take a current, then reduce the charging voltage as necessary to maintain 5 to 10 amps of charging current.

Chris at Octarine Services

Yup - that too.
Nigel is right - a little trickly conditioner can be left on without detriment. I have one permanently fitted. Just plug in and switch on. Done.
Also a battery isolator switch is worth considering if the car's not used much. Might even stop the more casual class of thief too.
Greybeard

Thanks for all your help. Tomorrow I will connect another charged battery via jump leads, then connect my trickle charger. As soon as that starts to charge I will disconnect the charged battery. Is that a good plan?
Colin
C Martin

Yes but you might not need to do that, if your trickle charger is a battery conditioner you can just connect it to the battery and be patient.

You need to have the battery disconnected from the car otherwise it's fighting the clock too - (as well as good practice, H&S, ect.).
Nigel Atkins

Grey,
you are a naughty boy -

"Also a battery isolator switch is worth considering if the car's not used much."

Nothing should be fitted that will further deter more frequent use.

It was sunny here this morning and afternoon.








Cold and wet in between though. :)
Nigel Atkins

Trickle charger might or might not have the oomph for the job. Maybe better using the "normal" charger you mentioned.
Disconnect the remote, charged battery first, in case the one being charged is gassing. You don't want sparks around it.
Edit: thanks to Nigel for the correction lol!
Maybe I ought to have suggested that as long as you have the jump leads on you could just start the car and take it out for a canter. Let the alternator have a go. At least its not like a modern with an engine management computer to get all sulky about battery voltage.
Greybeard

Only recently I used my Carcoon (Accumate) battery conditioner on my neighbour's very, very flat battery, it took well over 24 hours possibly 36 but I don't know as I forgot to check in between.

I was nearly tempted to get my 4 amp charger out but we waited instead.

You lads with your 8 amps and 5-10 amps, no patience of us younger generation, big hammers and heat torches instead of finesse.





:)
Nigel Atkins

Oh aye, by the way I reckon you're right about the clock. Mine did that too. Now it goes off with the isolator and I can't be ar*ed resetting it so I'm often tempted to chuck it away. The only thing that's stopped me is deciding what to put in its place to fill the hole.
Greybeard

Lol - the starter charger is rated at 250 amps ....
Chris at Octarine Services

I wish it was mine Chris ;)
Greybeard

Grey,
you could always fit an isolator with a bypass for the clock.

Or to fill the gap you could fit an oil pressure gauge or if you already have that, and better still, an oil temperature gauge so you can worry about the oil temperature in one part of the engine, especially if you have an oil cooler fitted without an oil stat.

Or a voltmeter or ammeter, unnecessary in a later car but so is a clock when the sun or stars are out.

Or a compass for when the sun are stars aren't out.

Or a modern multigauge that has a mix of functions, see what horsepower is used cruising on a flat road at 50mph - with different colours for each function.

Now where's that catalogue . . .

Nigel Atkins

250 amps! I didn't know you could get that many in one box, it must be the size of a double-wardrobe with as many knobs and dials as the TARDIS.

Not just a BFH but Thor's, I need a lie down.
Nigel Atkins

Grey,
what about a cluster of warning lights, temperatures too high or too low, over and under charging, pressure too high or too low, battery connected or not - interior light on. :)
Nigel Atkins

You might be onto something there. The triumphs I ran had a nice little cluster of idiot lights like pie segments in a round "clock". That's a thought.

THREAD DRIFT ALARM!!
Greybeard

Be better to have both lights and gauges - strips of each fixed under the dash - then we can also break into a radio and speaker console apertures, Prop would be proud of us, we you my ideas but your car, money, items and work - but it's the idea that counts, the seed. :)

Thread drift warning light! 🚨
Nigel Atkins

As there was mention of battery chargers I had a walk around Wem (Shropshire) this afternoon and wandered into an antique/collectors shop and found this battery charger brand new in box for £20. Needless to say it's now in my garage.
Rob


MG Moneypit


😲

Jammy!
Greybeard

Nigel
Actually a voltmeter IS useful. An alternator only needs to generate battery voltage (say 12.6v) to extinguish the red light. You cannot be sure it is charging properly (ok you can see if the headlights go brighter when you rev up at night but more difficult in daytime). I intend to fit one in the Frogeye. (An ammeter is ok but more difficut to wire up safely and reliably).
Bill Bretherton

Lol

Grey
I'd put a mirror in the hole and drive round to Nigels house and tell him what a good idea it was, his suggestion --
"you could always fit an isolator with a bypass for the clock. "

When it was the clock draining the battery--

He could then watch his lightbulb moment in your mirror---


William Revit

Aye Willy, the clock/battery controversy had dawned on me too. But I'm a gentle soul and didn't want to rub it in lol.
I like your thinking though.
I also wondered about one of those huge red emergency stop thump buttons to instantly kill all the electrics in a drama. Might look quite cool in a perverse, industrial chic kind of way, but maybe a little OTT, since I don't have an electric fuel pump.
Greybeard

Bill, there is another option for ammeters, which is common on industrial three phase supplies. Essentially there's a coil around the conductor which picks up a charge by induction and the meter reads the charge density (for want of a better term) and displays it as current. This would mean no need for heavy cables behind the dash carrying big amps looking for a place to short out.
It's sort of a first cousin to a clamp ammeter.
I don't know much about them yet, but I'm assuming they would be happy with DC too. For curiosity's sake I'm going to do a bit of reading about them.
Greybeard

There are amp meters that just lay on the battery cable for checking starter motor draw

My scope has an inductive pickup for the amp meter- acurate as anything, measures down to 0.1 amp --just clips on a battery cable, probably the most usefull part of the machine, well, not really, but it is handy
William Revit

Grey, Willy
My initial thought was that you can't have electromagnetic induction with steady DC so I did some reading. A DC clamp meter typically uses a hall effect device to detect current as I understand it. Maybe you can both add to this though. Interesting.
Bill Bretherton

Returning to somewhere close to the initial post, I can't comment on reviving batteries save that I have used Bat-aid tablets in the past and they have given a bit of life back to dying batteries.

I do, however, have quick release terminals on the battery. It's a two second job to open the bonnet and unclip them.

While my Sprite doesn't have anything that's officially live and operating when it's parked with the ignition off, the relatively new battery was draining mysteriously. I eventually tracked it down to a short in the horn circuit but there must have been so much resistance (rust?) in the way that the horn wasn't sounding. Unclipping the battery at least stopped the drainage.

My daughter gave me a conditioner for Christmas a couple of years ago. The plastic covered quick releases don't give access for the crocodile clips, but it's still only two seconds to unclip and and another couple to fit the croc clips. Result: no problems starting after a couple of weeks without use.

The plan is to install and Anderson plug so that I can leave the quick release terminals in place and just plug the charger/conditioner into it, making it a single stage two second job!

C
C Mee

Bill, Willy, Grey,
you could all be journalist but not lawyers. :)

"Or a voltmeter or ammeter, unnecessary in a later car"
- later cars have alternators, the number of times over years and decades that I've had charging problems with an alternator on various cars including classics is zero. Thinking about it the same is true with dynamos for me.

The clock by-pass was for Grey that isn't having problems with his clock drain the battery as he uses a charger (and possibly/hopefully use his midget more often).

My lawyer will be in contact with you three for defformation, no, deffirmation, er, deff... anyway my lawyer knows the terms and how to spell the words.

How very dare you even suggest that I could sometimes get fings wrong!





:)
Nigel Atkins

Returning to the original subject -
C (to save confusion),
now you've sorted the drain you should be able to leave (a standard electric load) Spridget for many weeks and not worry about the battery needing charge, if all electrics and battery are in good condition, clean, secure and protected and the battery was in reasonable charge.

I'd no idea what an Anderson plug was until I looked it up but with some battery conditioners you can buy, or make up your own, permanent connectors, and I see Accumate now have SAE connectors so you can't get it a*se-about-face.

Nigel Atkins

An update - after doing as suggested i.e. connecting up a fully charged battery and then my "normal" charger I finished up with a charger that indicates a fully charged battery, but that battery did not have enough oomph to do more than turn the engine over about three times. Its off to my friendly garage tomorrow for their opinion but I've already started to source another battery.
Thanks for all the help and advise. I will also fit an isolator to a battery terminal.
Colin
C Martin

Colin,
thanks for reporting back.

Unless it is truly a friendly garage they'll say you need a new battery. The battery is one of the most oversold parts on a car. However obviously sometimes the battery does need replacing, but many times it doesn't necessarily.

I don't have too much faith in the modern battery chargers that don't pick up a battery below a certain level and charge at too faster rate. Tortoise and hare, long and low recharged has always worked for me (but there would be a limit).

Even the RAC want to sell you one of their new batteries, they did this to my mate when he had to call them out. As he'd kept the old battery I took it off him to try to revive it which I did just by using my battery conditioner (and perhaps 4 amp charger but I can't remember). It kept its charge and he uses it as a spare 12v supply.

On the other hand I changed the battery on the Midget a few years back when I could have kept it longer because a pet hate of mine is a car that won't start and I can't be bothered connecting and disconnecting my battery conditioner as my Midget sits outside 365 days a year.

BTW old batteries have a small valve, £5 upwards (depending on size) for recycling.

Nigel Atkins

Nigel, I would trust my friendly garage with my life ( they do work on my daily cars brakes, among other things) They will know I will shop around for a new part if needed. If the battery is u/s I will leave it for them to "dispose" of.
Colin
C Martin

Colin,
that's great news to hear, I wish we had one locally.

Tayna are good for batteries, but where ever you source from before fitting check that the new battery is fully charged as they're not always.

I fitted Tayna's own Enduroline to my Midget and before that to my wife's previous daily very short-journeys modern car and both batteries proved to be very good.

I'm purely a satisfied customer so give above as information only.

https://www.tayna.co.uk/MG-Midget-Car-Battery
Nigel Atkins

I've got various battery chargers and a new charger/conditioner from Lidl.
None of the clever ones will work if the voltage is low - the Lidl one seems good but will only start pulse charging to restore a heavily discharged battery if there is 7.5 volts present.

So I resort to my trusty old 'Bradex' which is about 50 years old and it will start work on a totally flat battery ! (its only about 4 amp) but after a while if the battery comes up I can use a bigger one - well only about 8amp! to speed it up a bit. Or I just leave the old one on for a longer time but check battery temps - charging a knackered battery can boil the acid and it will expand out of the battery casing + dangerous fumes etc !

I agree with Nigel (again !) Tanya are good and also Battery Megastore have given me good service on numerous occasions.

R.
richard b

Colin, while you're sourcing a new battery it might be worth your while looking at suppliers of spares for lawn tractors.
Oddly enough many Mountfield (for example) machines use the same 019 (?) spec battery as Spridgets but for some reason their prices are better, or they were last time I looked.
Just a thought - might save you a few quid who knows?
Greybeard

This is an interesting read, for those of a curious frame of mind.

https://batteryuniversity.com/learn/article/charging_the_lead_acid_battery

By the bye Colin my isolator switch is fitted in the passenger side glove box. No need to open the bonnet. It's a Red Key type switch. They're not expensive but make sure it's rated for the starter current. Mine is 200A rated which is way over the top but lots of comfort factor.
Greybeard

My 1971 midget has always been fitted with a 038 battery, and I will go for the same I think. Tanya seem very reasonable and I quite like the look of the Lucas brand.
Hopefully I won't need a new one just yet.
C Martin

C Martin I think you're correct. 038. My bad - I'm on a rare weekend off duty so I've had some wine.
But my point remains that some lawn tractors use the same spec battery as Spridgets. And sometimes they are cheaper.
Thanks for the correction, very wise.
Greybeard

Is there some way if interpreting these 3 digit battery codes? Or are they just a simple reference number?
I have always selected batteries using their physical dimension and the type of terminal post, and then chosen the best CCA / price combination. Often batteries not specifically listed as being for classic cars are a good deal cheaper.

One other thing that impacts price is the guarantee period offered. Which in effect consists of an insurance premium added to the basic battery price. I don't believe it has anything to do with battery quality but is based on a probability of the number of owners who would attempt a claim within the purchased guarantee period.
GuyW

Codes - see here -

https://www.puretyre.co.uk/car-battery-specification-chart/
Chris at Octarine Services

Thanks Chris. I do already have a copy of a very similar table. What I was asking was if the battery perameters could be interpreted from the code, a bit like interpreting a modern VIN number, or a tyre code. That is rather different from simply looking up on a list. But I guess not.

Another source of cheap batteries is if you have a local old-style car breakers. Its amazing the number new batteries fitted to cars in their last few months of life! I guess as a car becomes difficult to start and in other ways unreliable, many owners think that replacing the battery is something straightforward they can do to fix it and that it is going to sort out all their problems! 6 months later and it terminally fails its MOT!

Take along a battery tester and look for clean batteries with a recent date stamp. It'l probably cost around £15
GuyW

Guy said: "Its amazing the number new batteries fitted to cars in their last few months of life!"

Great comment. Wish I'd remembered this from Prop's teaching.

Good call Guy.

If buying a new one take a bathroom scale and buy the heaviest one. It's surprising how much they vary.
Greybeard

Richard,
once again you have shown your great judgement, experience and intellect - the 4 amp charger I was referring to that I use is a Bradex.

My elderly neighbour bought mine for me new as a present perhaps 20-25+ years ago. As I used his same one to charge his car (but that another story).

It's a red plastic-cased, Bradex BX4 - "Powerful 4 amp charger". (Stellar Industries Ltd., Brighouse, W. Yorks.)

When I first connect it to a battery I can tell within seconds what state the battery might be in by just looking at where the needle is on the 'Charge Rate' (analogue of course) dial.

Then within a few minutes more I can tell if the charge period will be relatively short or long by how far the needle has moved from when I first connected.

The needle on mine never goes lower than the end of the first white square so if I really want to double check I put my Carcoon battery conditioner on for the very last bit but often that then goes immediately to it's green light.
Nigel Atkins

Hi, an update on my battery.....
After being on a trickle charger for just over a day my battery was indicated as being fully charged. However the checking instrument the garage used indicated a voltage of over 12volts but only 228CCA on a battery rated at 330CCA and a recommendation of "Replace Battery"
I shall replace in the car for starting up to move in and out of the garage but will replace before serious use.
Thanks to all for help and advise.
Colin
C Martin

Colin,
be careful about CCA figures, apart from the fact there are different standards of measurement so they can vary any battery will be below stated CCA after a time.

Have patience - put the battery on another slow and long(er) charge and either test it at the garage again or just put it on the car.

If you have a standard Spridget with standard electrics and all parts of the starting, ignition and recharging systems are in reasonable condition then starting the car isn't the same as with a lot of other cars and vehicles.

If the battery easily starts the car to move it in and out of the garage without taking the car for a reasonable length run or left running at fast idle for half an hour then the battery is probably fine, keep it until it isn't.
Nigel Atkins

Nigel, I put the battery back on my trickle charger and it went quickly to green indicating it was fully charged. I put it back on the car and it started very quickly. I let it idle to warm up to normal temp. I will put the trickle charger back on, but I would expect it maintain the current level of charge and not increase it. Is that a correct statement?
Colin
C Martin

Not quite. If it's a battery conditioner (also called a battery optimiser), then yes - it will go into a float charge maintenance state which is ideal for the battery, but a dumb trickle charger won't.
It might be useful to put a simple voltmeter across the battery terminals with the car running at fast idle to see what the alternator is doing. Or dynamo if you have one. It might give you more confidence to use the car without worrying about the battery.

228 CCA should be more than man enough for a Spridget engine. I'm inclined to agree with Nigel that spending beer coupons on a new battery might be a bit premature. A more than adequate optimiser can be found for not much more than about 20 quid and can be safely left connected full time.
Greybeard

(ETA: once again Grey has posted whilst I rewrote my post (3 times), now it's tea/dinner time)

Colin,
er, yes and no.

Which make and model of trickle charger are you referring to?

Many and most new ones will top up the missing charge and maintain the full charge - so depending on your battery state the charger should top up its charge if it needs it and maintain this topped up charge.

Electronics can be affected if stored in somewhere very cold and if used straight from cold might not work properly so it's best to warm them slightly by taking them somewhere a bit warmer to warm up a bit, or plug-in and use to warm themselves with use but give them time to warm before you take notice of any measures off them.

It might be your charger is reading correctly and your battery won't improve but leaving a conditioning charge on won't do any harm and could do some good.

The test for the battery is continued high drain such as starting the car a good number of times in quick succession. If the battery can do this then it is definitely worth recharging and keeping.
Nigel Atkins

I've got a fairly old charger with a high and low setting that I rarely use, but I have a couple of trickle chargers from Aldi or Lidl that I put on to keep the batteries charged, I also use them on a large spare battery that I use for jump starts (my neighbours knock for me sometimes) and a leisure battery for my caravan.
The 228CCA certainly had no problem starting the midget today.
Colin
C Martin

The old charger might be very good, I'd use it on low and at the end use the trickle charger (especially if it's a conditioner as I suspect it might be).

The trickle charger my neighbour got from Lidl was a charger/conditioner which is it's a battery charger that switches itself to a conditioner when the battery is fully charged.

I was being too subtle before, very unlike me, Colin when all else fails you could always try RTfM (read the manual). If you've not kept the user instructions then tut, tut. :)

The checking instrument the garage used if it's modern one might be more suited to batteries for use in modern vehicles with their higher loads and a lot less tolerance than a Spridget would give a battery. Plus of course you don't know its accuracy, things can go out of calibration, faulty from conditions of use, age, use and abuse, or it might be 100% accurate, I can't know either way but the battery started your car (no high drain drop test though).

With the three batteries you mention, plus probably at least one other, you don't want to be replacing a battery if it is still good.

Nigel Atkins

This thread was discussed between 20/02/2020 and 25/02/2020

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