I can remove the output wire at the alternator to do this?Disconnect the alternator and see if the noise goes away.
Yes that will work, that will "turn off the alternator". If the sound goes away that will let you know that was the problem.I can remove the output wire at the alternator to do this?
You can either swap alternators or have that one fixed on an original or restored car.I UNPLUGED THE 2 WIRE PLUG AT THE REAR OF THE ALTERNATOR AND THE NOISE STOP,S THE RADIO SOUNDS FINE UNTIL I PLUG IT BACK IN ?![]()
Still haven't pulled the alt wire to test this as a source of noise... Does an HEI have a condenser? I don't recall seeing one last time I pulled the cap. My setup is a factory regulator. I've been thinking about upgrading to a 3-wire, internally regulated. Thanks!Are your condensers (capacitors) hooked up? There should be one on your voltage regulator and another at your distributor or coil.
AM radios are susceptible to any electric "noise" like lightning or electric trains. Your ignition system is no different.
If you didn't see one near the coil or distributor, both Mallory and MSD make noise filters. Your factory voltage regulator should have something like whats pictured below coming off the side spade and the case grounded out with the regulator chassis.Still haven't pulled the alt wire to test this as a source of noise... Does an HEI have a condenser? I don't recall seeing one last time I pulled the cap. My setup is a factory regulator. I've been thinking about upgrading to a 3-wire, internally regulated. Thanks!
Yes, my external regulator does have a capacitor. I pulled my red/hot alternator wire off and still have radio noise. I have a GM HEI with MSD "Street Fire" wires #5551. They're for a stock HEI application and have EMI supression. My plugs are Champion Copper Plus, RJ12YC resistor. Did a new cap/rotor/wires/plugs just recently.If you didn't see one near the coil or distributor, both Mallory and MSD make noise filters. Your factory voltage regulator should have something like whats pictured below coming off the side spade and the case grounded out with the regulator chassis.
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Hmm, did you try double checking all the plug and coil wires to make sure they're on tight? It certainly wouldn't hurt to replace the regulator condenser like Custom Jim said..should be a $4 part. The next thing I guess would be to check the ground on your radio. Make sure the radio is grounded as close as possible..i.e. don't use the factory harness ground unless it terminates nearby.Yes, my external regulator does have a capacitor. I pulled my red/hot alternator wire off and still have radio noise. I have a GM HEI with MSD "Street Fire" wires #5551. They're for a stock HEI application and have EMI supression. My plugs are Champion Copper Plus, RJ12YC resistor. Did a new cap/rotor/wires/plugs just recently.
Pulled my antenna connector from the radio and still ignition noise.
I wonder if my capacitor needs to be replaced? And switch to different plugs? The noise source is definitely somewhere in my ignition. Thanks!
Thanks Jack, I'll check to make sure my wires are on good and tight. I suspected the radio at first and send it back for a replacement board and to confirm everything is good. Yes, I hear the static noise on AM and FM, makes no difference. With no volume I can here the noise. I'm going to replace the condenser in my HEI and voltage regulator. Hopefully this will cure it. Oh, and I have a good chassis ground near the radio. I tried moving the ground to different locations, no improvement.Hmm, did you try double checking all the plug and coil wires to make sure they're on tight? It certainly wouldn't hurt to replace the regulator condenser like Custom Jim said..should be a $4 part. The next thing I guess would be to check the ground on your radio. Make sure the radio is grounded as close as possible..i.e. don't use the factory harness ground unless it terminates nearby.
I just saw you had the radio upgraded to AM/FM. When reassembling the radio someone might have forgotten to solder or connect all the ground points making the radio chassis an ineffective shield (or something along those lines). I'd check into that possibility as well. BTW, If you're hearing noise in FM mode, then the problem is not in your receiver but in the radios audio amplifier circuit (definitely a shielding issue).
Ahh...you're getting noise with the volume all the way down. I wish you had said that earlier. That sounds like a ground loop, i.e. more than one grounding point on the radio. Think about this for a sec...when you're volume is all the way down, the input to the audio amp is "grounded out" which ideally doesn't let anything through to the amp because there is no signal to amplify. If a ground loop is present, it acts as an antenna, picking up noise and feeding a signal into the amp through the ground. I don't know what else it would be. You might want to ask a CB or HAM guy about it.Thanks Jack, I'll check to make sure my wires are on good and tight. I suspected the radio at first and send it back for a replacement board and to confirm everything is good. Yes, I hear the static noise on AM and FM, makes no difference. With no volume I can here the noise. I'm going to replace the condenser in my HEI and voltage regulator. Hopefully this will cure it. Oh, and I have a good chassis ground near the radio. I tried moving the ground to different locations, no improvement.