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MG MGB Technical - Dead Electronics!?!

Hi,
My 1977 MGB sat for about 2 weeks and when I went to start it up it tried to start and got usual trying to start stuff, starter click and engine trying to fire up(usually starts after 2-3 x after setting)but after 3 tries nothing, only a click. Thought battery may be dead so I hooked up the charger and waited 30min. Charger said battery charged so I tried starting the car and nothing. After I disconnected the charger there was zero electronics in the car, no door light, no radio, no flshers, etc totally dead. I hooked the charger back up to battery and it said battery charged so I tried starting with charger attached. Got all the electronics back (with chargr on) but when cranked engine all I got was a "buzzer" tye sound from the started area.
1. Can the battery be dead/bad even though charger said it was fully charged?
2. Could the starter relay have gone bad?
3. Did I just blow a few fuses?

The fact I have 0 electrics without the charger makes me think its the battery but....with charger on wcar won't crank.

Any input greatly accepted.
Joe Fabian

Check your battery cable connections on both ends. If you have the battery cables with the molded on battery connectors give the cable a good pull and see if it pops out. They are known to corrode internally, while they look fine they may be shot. You can also just start feeling the connections after trying to start the car, the poor connetion will get warm.
John H

Try a different battery. Your battery might be knackered. Standard lead acid batteries (as opposed to deep cycle batteries) can't take a total discharge, and they can't go below 50% charge more than around 7 or 8 times before they become fairly unusable. Theyre more about peak amps than amp hours. Firstly, I'd see if the car will start using a good set of jump leads from a running car with a beefy enough alternator (not a 1980's toyota starlet for example). If it still won't your next port of call is your connectors on the starting motor. Remove them, clean or replace them, and clean the terminal post on the motor. Check for frayed connections. If that still doesn't work, take a look at John Twists video on youtube about starter motor problems. He gives some good ways of diagnosing faults. But seriously, Id say all it is is your battery. Im a car salesman in a big car dealership and we have to contend with dead batteries all the time. If the battery has been completely discharged, we'll generally just replace the battery before the car gets sold cause its only going to give us more trouble otherwise and the customer won't be happy.
Ross Kelly

Don't forget to check the ground strap between the body and the transmission.
Pat
Pat Harrison

Did you clean the battery terminals?
Tom

With no lights or anything else it wouldn't just be the engine ground strap, but it could be contributory. Sounds like battery connectors, check both ends of the ground strap, but also the battery cable and browns at the solenoid.
Paul Hunt2

Thanks all. It was the battery. After charging overnight all is well again, well, as well as MG electronics can be.
Joe Fabian

This thread was discussed between 02/05/2008 and 08/05/2008

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