Electrical Overcharging

[zzmac]

Ok, I just hooked up my multimeter with the egine running and it was bang on 14.5 by the looks of it.

So... can I assume that it was just the gauge? If there was something drawing the current wouldn't it be constant? Also, the other day, as soon as I parked it after the gauge was showing over 25, I felt the battery and it was cool. Would that also point to a misbehaving gauge?

[zzmac]

One other thing, the gauge is now showing properly coinciding with the multimeter reading.

[Bartruff1]

Those of us so old to have driven post war (WWII) english cars or riden bikes like a BSA or Triumph had so much trouble with Lucas that we are always suspicious about any electrical component made by them..not fair...but hey.. life is not fair and it is always a good idea to try the simplest solution first..

[FWB]

Originally Posted by Bartruff1

Those of us so old to have driven post war (WWII) english cars or riden bikes like a BSA or Triumph had so much trouble with Lucas that we are always suspicious about any electrical component made by them..not fair...but hey.. life is not fair and it is always a good idea to try the simplest solution first..

all this lucas talk makes my zenon diode malfunction.........

[patrickt]

Originally Posted by zzmac

So... can I assume that it was just the gauge? If there was something drawing the current wouldn't it be constant? Also, the other day, as soon as I parked it after the gauge was showing over 25, I felt the battery and it was cool.

Maybe, but it could still be a "sticking" voltage regulator. Were you able to find your VR? If it happens again what you should do is rap your knuckles on the amp gauge and see if it returns to normal. If that doesn't do it, rap on the voltage regulator and see if it returns to normal. This is where a little cigarette lighter volt meter helps. If the amp gauge swings all the way to the right and your volt meter also registers 17 volts then that tells you it's not a malfunctioning amp gauge.

[DougD]

A voltmeter reads VOLTS, an ammeter reads AMPS.

The ammeter reading will vary by the load imposed on the circuit. Were your fans running? Headlights on? Anything else that cycles on/off or operates intermittently?

[patrickt]

Originally Posted by DougD

A voltmeter reads VOLTS, an ammeter reads AMPS.

The ammeter reading will vary by the load imposed on the circuit. Were your fans running? Headlights on? Anything else that cycles on/off or operates intermittently?

Assuming his car is wired normally, the ammeter will sit between the battery and the entire system's load and alternator. Increasing or decreasing the load should not affect the current running through the ammeter if the alternator/VR are performing properly -- and certainly will not make the ammeter point over in the plus direction. He really ought to buy that inductive ammeter of mine that I show in my previous post. It's a hundred bucks well spent. It sounds like he might just have a misbehaving gauge, and seeing a "normal" volt reading doesn't really tell you too much about current flow. Putting an inductive gauge on the wire would tell him for sure. Not to mention how cool it is to capture the intitial draw of heavy items, like fan motors, when they come on. MSD boxes usually have their feed sit on the "battery" side of the ammeter, though -- and they make a big deal about that in their instructions. Big stereos sometimes sit there too. But it boils down to either his gauge is broken, or the current is going somewhere over to the battery side of the ammeter's circuitry.