MG T-ABC

Hello all, just fitted a new voltage regulator to my TC to fix a no charge problem. Seems to be working fine but wondered if the rate of 10 amps as shown on the gauge is high? Of course I dont know how accurate the gauge is. With headlamps on etc is is just on the charge side of zero so its holding it's own but will 10 amps cook the battery?

Thanks.

just trying to determine whats up with one of my dynamo's on TC1472. Tested to show only charging at 3amps. I checked with a fellow guro and he said they should show 13amp ... the regulator then determines to let it, or stop it.
I've removed my dynamo so it can now be checked to why and replaced it with one from TC4245 to try for a while. The red light dims but doesnt go out, nor does it register much at all on the ammeter gauge ... so a little thinking and testing to try.

I don't have first hand knowledge of the TC charging system but I assume it is similar to my TD's. First check the generator to determine if it is generating the proper voltage. At about 1500 rpm it should be a little above 14 volts at which point the red ignition light should go dark. It really won't go much above the 14 volts ever. There are sites to show how to test the generator in while in the car. If the generator is okay then the problem most like is in the regulator. I am assuming that the TC dynamo output voltage should be the same as the TD.. You could also install a temporary ammeter in the circuit to check the dash gage although the dash unit is usually pretty accurate. Not much to go wrong with them.

Steve, sounds like your battery is pretty discharged. Best to charge it up with a charger whenever it gets low like that. What you are doing you will not likely burn up the voltage regulator, but rather the dynamo. If your battery is fully charged, then the regulator might need adjustment. You can have a regulator set up in such a way that you will cook the battery by overcharging it.

Thanks, I'll charge the battery up and see what the meter reads under 'normal' conditions. What sort of amps should I see running without lights etc? My old bikes seem to just waver into positive.

These may help:

http://www.mg-tabc.org/library/lucas_check_charging.pdf (by Al Moss, 1981)

http://www.mg-tabc.org/library/lucas_ge ... _tests.pdf (Factory manual)

10 Amps won't kill your battery so long as the regulator is working properly and reduces current to the battery when it approaches full. A plug-in battery charger puts out more than 10 amps on full charge, often as much as 30 amps intermittently It may also be worth checking the calibration of your amp gauge to be sure the readings are accurate.

Thank you. Now the battery is fully charged the reading has come down and just shows 2 or 3 amps and all seems well. Thanks again.