Battery charging

Technical MGB discussion
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Charles Farran
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Re: Battery charging

Post by Charles Farran »

I appreciate my car is a later one with a cigar lighter socket that is permanently live. I have a CTEK & paid for (admittedly not cheap) for the small connector plug lead & simply plug in & then do the opposite when i want to take the car out. Saves all the hassle. Earlier cars , without a cigar lighter could be permanently wired up with the short lead & socket provided with the CTEK under the bonnet to a suitable live end of the fuse box & a ground. (Replacing the "eye contact" with a suitable insulated female spade type connector etc. leaving the "eye contact" of the negative to fix to a suitable ground). Given the low demands, current wise of the CTEK , there should be no issues with the original MGB wiring. (I was always advised to disconnect the battery from the car when using a traditional charger).
The flexibility of my arrangement is that i can use my CTEK on my "modern" which has the battery under the boot floor , but a big + terminal under the bonnet. I simply swap the cigar lighter lead for one with crocodile clips.
Cheers
Charles
1980 Roadster
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Bumpa
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Re: Battery charging

Post by Bumpa »

On the 1971 car I am rebuilding I have mounted a terminal block by the pedal box with a high amperage cable going down to the starter motor. The block has a snap on lid to keep the electricity safely under cover. Since the starter motor is connected directly to the battery, this is as good as plugging into the battery directly. For charging with my Accumate smart charger I clip the positive lead in the block and the negative lead on to a bolt on the engine. Having the connector under the bonnet is useful when I want to use 12v appliances like my timing gun, or an inspection lamp.
Battery connector.jpg
Mike
1969 MGB GTV8 3.9 Conversion. Many classics have passed through my hands but the faithful BGT V8 is the last man standing.
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Bumpa
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Re: Battery charging

Post by Bumpa »

I should have mentioned that the biggest benefit of the under bonnet terminal is that the car can be jump started from there, or indeed it can be used to jump another car. This is the connector I used.
https://www.vehiclewiringproducts.co.uk ... x-two-stud
Mike
1969 MGB GTV8 3.9 Conversion. Many classics have passed through my hands but the faithful BGT V8 is the last man standing.
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Michael Barclay
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Re: Battery charging

Post by Michael Barclay »

Hi Geoff
If your car has a factory fitted cigarette lighter then you can use this as a useful way of charging the battery as it is permanently live even when the ignition is turned off. I use a CTEK battery charger connected via their cigarette lighter plug accessory, allows me to conveniently connect and disconnect the charger when I drive or park the car in the garage.
Mike Barclay
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Paul Heffernan
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Re: Battery charging

Post by Paul Heffernan »

I'd also vote for the hard wired smart charger option with the SAE connector on a short lead through the bulkhead, easily accessed behind the seat . Mine has a battery cut out switch also fitted on the rear bulk head, just behind the seat. Ideal if the car is garaged and there's a plug socket handy. Never had a problem with the installation.
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Re: Battery charging

Post by Vic Butler »

Further to my earlier post, I disconnected the Accurate from the battery recently so I could crank the engine over on the starter as I haven't been able to work on it for a couple of years due to hip problems (now cured) and I wanted to check the engine was free and the clutch wasn't stuck. All ok so I reconnected the Accurate and the yellow light came on to indicate the battery needed charging. Today, 2 days on the yellow light was still on and the charger was too hot to touch. I immediately disconnected it and checked the battery voltage. It was 12.94! Obviously the charger was overcharging so as a temporary measure I connected a conventional battery charger as there is an electrical leak which I can't trace. I believe it's down to the replacement steering lock/ignition switch I fitted years ago as that's when I noticed the battery was running down.
A new Accumate will be ordered. Fortunately I don't need the wiring to the battery or the extension lead as I have them already.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
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Bumpa
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Re: Battery charging

Post by Bumpa »

12.94 volts is not excessive. I've just measured my MGB's batteries as it has been on the Accumate for days and the green light is on. The voltage is 13.42. When you are driving the car it would not be unusual for the alternator to be supplying 14 volts to the batteries. The Accumate does get hot when the batteries need a lot of topping up. It isn't really designed for that. It is meant to maintain an already charged battery.
Mike
1969 MGB GTV8 3.9 Conversion. Many classics have passed through my hands but the faithful BGT V8 is the last man standing.
Vic Butler
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Re: Battery charging

Post by Vic Butler »

Despite the voltmeter reading for the battery the battery charger, 24 hours later, is indicating that the battery is coming up to be fully charged. When I cranked the engine over the starter motor was sluggish as if the battery was down on charge.
Anyway the replacement Accumate will be delivered tomorrow so before I connect it I'll make sure the battery is fully charged.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
Donie
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Re: Battery charging

Post by Donie »

Hi Guys, and Gals.........and GeoffK

I can't speak highly enough about CTEK. They are superb battery mainteners.

They come with both 'charging side' lead types, crocodile and eyelet with quick connector plug, and helps make them a wonderful bit of kit,

Connecting the eyelet lead to the battery permanently takes only 15 minutes or less and only requires unscrewing the nuts from both battery terminals, and putting one the eyelets in the correct colour sequence, and it makes fitting a doddle. The quick connector can be left hanging in the footwell behind the drivers seat with the battery cover panel permanently in place.
Vic Butler
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Re: Battery charging

Post by Vic Butler »

I don't know about the corded CTek chargers but I 've got a cordless one which I use on the Land Rover which is parked outside and it does exactly what it "says on the tin!"
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
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