1967 Amp gauge

[Jeremy H.]

I have a reading of +20 at idle and close to +35 to +40 at higher rpm's. Does that mean that the alternator is not working? I think that's what that means but I wanted to make sure before I asked Pirkle about it?

Thanks

Jeremy hedges

[John H.]

Re: 1967 Amp gauge

That usually means that the battery is low and the alternator is working hard to charge it, or the voltage regulator needs attention. What's the voltage across the battery terminals with the engine running at 1500 rpm?

[Jeremy H.]

Re: 1967 Amp gauge

I will check it tomorrow. What does it need to be?

[Bill I.]

Re: 1967 Amp gauge

Jeremy, if I may, I'll answer for John, it should be around 14.5 to 15. Anything higher indicates problem with the VR. Bill.

[John H.]

Re: 1967 Amp gauge

Engine-off, you should see 12.4-12.6 volts across the battery terminals for a fully-charged battery. With the engine running at 1500 rpm, you should see between 13.8-14.5 volts or so; as Bill noted, if you see more than 15 volts, there's a voltage regulator problem.

[Gerard F.]

Re: 1967 Amp gauge

Jeremy,

The voltage adjustment at the voltage regulator on a 67 is a snap. Just follow the service manual.

Here's a convenient way to measure the voltage:



Plugs into the cigar lighter socket. Available at Walmart, pretty cheap.
I keep it in all the time just to monitor the battery condition.

After I had restored my original alternator with a 60 amp rotor/stator, I was wondering why I kept cooking my lead acid battery. The voltage was set too high and above 15v. So I got this gadget and adjusted it down.

Adjust it when it is hot, as the voltage will always be higher when the VR is cold. If you have a maintenance free or gel battery (which I have now), keep your voltage below 14v, preferably in the mid 13 range. Above 15v with these type batteries can ruin them.

[Wayne M.]

Re: 1967 Amp gauge

.... Available at Walmart, pretty cheap ....

Jerry ---what a neat gizmo . Hope Walmart carrys them up here in Canada. Thanks for posting this diagnostic tool.

[Rick S.]

Re: 1967 Amp gauge

One other thing to check is the ground wire at the voltage regulator. I had my voltage regulator and alternator rebuilt by John Pirkle earlier this year and started to get spikes from negative to a positive read. Called John and he suggested to check the ground and that was my problem.
Rick