Voltage regulation with an alternator

Post by **southerly95** » Mon Jul 28, 2008 6:41 pm

What happens to the standard voltage regulator when an alternator is fitted? Does it still operate or is all the control through the alternator?

Thanks, John

Post by **PSL184** » Mon Jul 28, 2008 6:48 pm

Regulation is through the alternator. The box stays in place to feed the circuits but the charging side of things is disconnected.

Post by **bmcecosse** » Tue Jul 29, 2008 10:55 am

Yes - you can throw it away or leave it in place to keep the wiring tidy. But the Dynamo and Field connections are not used - the alternator is connected directly to the main power connection on the solenoid - and the alternator field connection comes from the 'ignition warning' lamp.

Post by **southerly95** » Tue Jul 29, 2008 11:02 pm

Thanks for replies, I was wondering what happenens to the voltage stabiliser on the back of the speedo. I think the two replies above refer to the control box. Regards, John

Post by **bmcecosse** » Tue Jul 29, 2008 11:09 pm

It remains ! It gives a 'steady' 10 volts to the fuel gauge - and to an electric temp gauge if you fit one. Actually - it's not 'steady' at all - it's a bimetallic strip that makes and breaks - giving similar effect to flat 10v to the 'hot wire' instruments.

Post by **southerly95** » Thu Aug 14, 2008 9:37 pm

Ok good - could I use the regulated 10v supply to feed the ditributor and coil to stop the coil from getting hot and failing every 2/3 months?? Getting desparate - you can tell! Thanks, John

Post by **alex_holden** » Thu Aug 14, 2008 9:40 pm

No, you can't do that. Are you sure you have the right type of coil fitted? How is it mounted?

Post by **bmcecosse** » Thu Aug 14, 2008 10:10 pm

If you have a Mini 9 volt coil - then it will certainly overheat! My coil is as old as the car - it doesn't overheat - they are extremely reliable.

Post by **southerly95** » Fri Aug 15, 2008 11:46 pm

The coil that failed was a gold Lucas 12v sports, the second in a year with one from DSN inbetween. Minispares thankfully replaced the last one.

Coil is mounted vertically on the offside wing just behind the washer bottle but is recent move so will see if that helps.

Car went in yesterday to local garage to have an autoelectrician look over it. Circuitry is fine except that the base plate on the distributor is very worn affecting points opening and dwell angle etc.

It's all a puzzle, I will see if I can get an old one like bmecosse I think!

Post by **Alec** » Sat Aug 16, 2008 7:09 am

Hello S95,

you don't, by any chance, have a habit of leaving the ignition on without the engine running, say to run a radio when stopped etc. This does a coil no good if the points happen to be closed?

Alec

Post by **bmcecosse** » Sat Aug 16, 2008 10:09 pm

If you had a coil from Minispares - it would be a Mini 9 volt coil!

Post by **southerly95** » Sun Aug 17, 2008 1:47 pm

Bmecosse, Minispares do some good stuff for A series engines and seem to be the cheapest for good quality 12v coils - see link below

http://www.minispares.com/Product.aspx?pid=33876

Post by **bmcecosse** » Sun Aug 17, 2008 10:02 pm

Yes - I have bought from Minispares in the past - but mostly for my Mini!! If you are sure it's rated for 12 volts - then fine ! It won't burn out!!

Post by **grumpygrandad** » Mon Aug 18, 2008 8:42 pm

i thought some coils should not be mounted up right