Amp light problem

Lee ODell

On my 52 Hudson Hornet the Amp light used to work right. Then it stopped lighting. The brushes have been replaced as well as the regulator. However, neither turned out needing to be replaced. Now the light comes on like it should. It glows bright red while idling now, then dims so you can barely see it, but as the car speeds up the light increases in intensity. By 35 MPH in third gear it is glowing bright red. Shift into 4th the light dims again, but never totally goes out. As the speed increases the glow gets brighter. By 50-55 MPH the light is glowing bright red again. I had everything with the generator check and all is well there. The voltage to the battery checks OK within specs.

Any cure for this problem will be greatly appreciated.

Lee O'Dell

[Deleted User]

Take the generator and voltage regulator to an electrical repair shop and have them set the regulator to the generator. You can't do one with out the other. Walt.

Lee ODell

I forgot to mention the reason for why the light sent out was the bulb burned out. Replacing the bulb brought the light back on.

Walt, the new regulator came from Dave Kostansek. I gave him the number off the generator to be sure I got the right regulator. Will doing what you said eliminate the odd amp lighting situation? I had an automotive shop check out the charging system. He couldn't determine why the light was acting like this even though he said the charging system was working.

[Deleted User]

agree with the last, but in my opinion you may have a faulty generator field. If you are not compatent with a good multi metre and know your way around electrics. Take it to an auto electrician. otherwise pull the generator apart and check that the fields dont have a short to ground, further check that the fields are within resistance tollerances (when a field becomes oil soaked, or other liquids penertratae the field winding it can cause the field winding insulation to fail. If the slip ring on the main armature is worn or crap has built up in the insulation groovs it will cause the globe to do wierd things.

Another good test to run is check with a multi metre the voltage or amp draw while the vehicle is running.

Park_W

The symptoms described suggest the generator may be overcharging. Doing as Walt suggests should reveal if that's the case. Take the car to a reputable shop and have them check the voltage and amperage as the rpm is increased. Most parts stores that sell batteries and regulators have test equipment to do this, and typically the test is at no charge (no pun intended!). The only question is whether the person conducting the tests knows what he or she is doing.

[Deleted User]

I just finished a 39 C C S 8, and it was doing just like you say your car is doing. Had the generator rebuilt and voltage regulator set to 6.7 to 7.2 volts and 29 to 32 amps at 1800 RPM's. All is fine now. Even though the voltage regulator is new, it must be set with the generator. Walt.

russmaas

did you polarize the voltage reg. after install. Need to touch the "bat" and "arm" with a jumper wire when replacing either or.

Park_W

Russ, there's nothing in a regulator that needs polarizing. A generator may need to be polarized on rare occasion. But in this particular case the symptoms don't point to a polarization problem.

Lee ODell

Yes, charging system polarization was done. From what I have spent so far I could have changed to 12V and had $$$$ left over. Trying to keep it original.

Thanks Walt and everyone for your help. I want to get it reliable for the trip to the Nationals this summer. The charging system has been a persistant problem.

Lee

Lee ODell

The amp light is workiing like it is suppose to now. Charging system is in spec..

The solution was none of the above. It was the circuit breaker above the steering collumn.

Lee O'Dell

Park_W

Lee, that implies that circuit breaker powers the ignition switch. I didn't think the ignition was run through a CB. Has the car been re-wired?

Lee ODell

Park,
The mechanic that cured the Amp Light problem told me it was the circuit breaker and about the different watt #55 bulbs. I'll look under the dash to see if any wiring changes have been made.
Lee

Park_W

Lee, my recollection from when I rehabbed my '51 and had the dash all apart, was that the ignition switch supply wire came from that CB, but from the "supply side" terminal that's connected direct to power at the starter solenoid. Evidently Hudson didn't want the engine to quit if a short circuit elsewhere caused that breaker to open. It's easy to imagine that at some time someone could have had it off and reconnected it to the "downstream" side of the CB.

[Deleted User]

That is exactly how it is on my 54 coupe and like Park said it would be easy to get it backwards if not paying attention...
Bob Hickson

Lee ODell

All the wiring looks original except the wires going up the steering collum to the horn and turn signal sw. I noticed all the wire attaching screw threads are shinny so there may have been a mixup with the wires and he corrected it. I recall him mentioning the possibility of wires being crossed before he started checking it out. Looking at the wiring schematic I can see there is no circuit breaker in wire to the Amp Light. I'm glad the Amp Light works properly now.

Thanks everyone for pointing out how easy it is to cross wires.

Lee O'Dell