Connect a 20v meter between the control box 'D' terminal and a good ground.
Switch on the headlamps and slowly increase the engine rpms whilst watching
the voltmeter. The voltage should steadily rise then drop slightly just as
the cut-out relay operates, the voltage just before the slight drop should
be between12.7 and 13.3 volts.
If your voltage is higher than this then the cut-out relay requires
adjustment, adjust the cam until the right voltage is obtained.
If the voltage is correct then switch off the headlights, disconnect the
wiring from the dynamo D and F terminals and connect these terminals
together. Connect a 20v meter between here and ground. Slowly increase the
engine revs whilst watching the voltage. Do not allow the voltage to reach
20v, and you should not have to exceed 1000 rpm. Do not race the engine to
achieve the voltage. If it takes more than 1000 rpm there is a problem in
the dynamo, possibly worn brushes or a worn commutator.
PaulH.
----- Original Message -----
From: Sam Perera <sam_perera@yahoo.com>
To: <mgs@autox.team.net>
Sent: Tuesday, January 25, 2000 3:29 PM
Subject: MGA Charging problem
> I'm having problems on my 60 MGA with the charging
> system. When it is idle, there is absolutely no power
> reaching the battery - it idles at about 1000rpm. I
> almost have to rev the engine to 2000rpm before I see
> any chrage back to the battery. The system is still on
> the generator with a negative ground 12v system. I
> also have an ammeter attched which allows me to see
> the + and - charge as the revs decrease or increases.
> Its also a brand new battery. I have been checking the
> system with a cheap alternator/generator battery
> tester with led lights.
>
> Is there anyway to correc this problem or even check
> if it is normal etc ...
>
> Thanks
>
> Sam
>
> =====
> Sam Perera,
> Houston, USA
> http://members.tripod.com/sperera/
> Do You Yahoo!?
>
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