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VelodromeRacer

VelodromeRacer

Jedi Trainee
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I don't want to think my volt regulator or generator have suddenly gone bad but.....

Suddenly, even though so far today the car starts right up, the ignition light does not go out after starting, it stays on.

Any thoughts on what to check?
 
Start with a simple check of the drive belt. Make sure it's there and tensioned properly. If that's OK move on to the basic volt meter check across the battery terminals. With the engine off, you should see somewhere between 12 and 13 volts. Start the engine hold the RPM near 1000. Return to the battery and measure the voltage again. You should see a 1 to 1.5V increase over what you saw with the engine off. If you see more than 15V, you can assume the problem is probably in the control box. If it has not increased it could be the control box or generator.

You can make a couple of generator measurements in the car. Remove the two wires from the generator. Check each for continuity back to the control box. If they're OK, make up a test jumper. This jumper will go between the two terminals on the back of the generator when the regular wires to the control box are removed. The jumper needs to have a bare spade lug so you can probe it with your volt meter. Start the car and connect your volt meter between the jumper and chassis ground. Note the reading. Have an assistant slowly bring the RPM up to 1000. The voltage should increase steadily but not exceed 20V.

If the meter shows no voltage, examine the brushes for wear. A reading close to 1V indicates a potential problem with the field windings. A reading close to 5V indicates a problem with the armature.

These steps were paraphrased from the AutoBook series of manuals.
 
Thanks,
Looks like I am going to have a busy day Saturday!

I had bought a amp gauge to install in the car a while back, do you know of any good instructions as to what or where I should wire it in?
 
Put the Amp meter in the Bin and get a voltmeter. Much safer and easier to integrate.---Keoke
 
Wiring for Ammeter or Voltmeter
A short description of how to wire in an ammeter or voltmeterfor your car.

The ammeter shows direction and rate of current to and from thebattery. Under normal conditions, the meter should show a (small) charge. This will be higher after starting, but probably never more than 10A, and often about 1A. If you see a discharge reading (other than maybe at tickover) you're running on borrowed time.

The voltmeter also indicates whether the battery is being charged. A reading of ~12V indicates that there is no current flowing into or out of the battery. Less than 12V indicates discharge (typically 8V when cranking the starter) and 13-14V is a healthy charging voltage. More than 15V when charging indicates a faulty regulator on the alternator.

A voltmeter actually shows more information than the ammeter, and is also safer to wire insince it takes no current and this allows the use of a small (1A or less) fuse. The ammeter needs to take the full normal load. This is 30A or so for a Seven, but add a few extra lights etc. andit could be more.

Here's an artistic pic. of how both could be wired in.

https://www.houlihane.co.uk/amps.htm
 
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