C2 Am/fm Radio Noise

[Jim R.]

Is there anything you can do to get rid of the SCREECHING when you first turn on your radio without removing the radio from the car i'm assuming it is dust on the tuner knob, also is this a deduct on opps. any radio guy's out there.

[Bill I.]

Re: C2 Am/fm Radio Noise

Jim, get a hold of some contact cleaner in a spray can, take off the knob, spray on the shaft while rotating it a few times, you might get lucky. Bill.

[Jim R.]

Re: C2 Am/fm Radio Noise

Thanks bill i will give that a try.......jim

[Randy S.]

Re: C2 Am/fm Radio Noise

Jim,

If that doesn't work remove the side radio panels and try to remove the radio from the car. I never could get it all the way out but did get enough clearance to get a good shot of contact cleaner into the tuner from some of the open holes on the case.
No more pop when I touched the volume knob.

Randy

[Mike M.]

Re: C2 Am/fm Radio Noise

Sorry, Jim, but yes, that would be a "Fail".
Good Luck
HaND

[Stuart F.]

Re: C2 Am/fm Radio Noise

There is a trick to removing the radio, but I too had to learn it over again every time. It will come out. You just have to turn it a certain way. I am past that now since I put in a modern am/fm w/ cassette and CD capable. They have many more features and are half the size. My original am/fm rests peacfully wrapped up in a nice box for someone else to deal with after I'm gone, cause I'll never touch it again.

Stu Fox

[Alan D.]

Re: C2 Am/fm Radio Noise

If the contact cleaner does not work try a little
oil. An old trick, but not a radio guy so follow the other advice first.

[Jack H.]

Re: C2 Am/fm Radio Noise

I'm not sure we're all on the same vine here... I know I'm a little 'lost' with the description of the radio SCREECHING in response to turn-on/warm-up.

The components used for power and volume control were NOT of high quality. By that I mean the volume pot isn't a sealed unit and they're notorious for attracting airborne crud (that's a high tech term) that results in what electrical techs call 'rumble'.

That's a 'scratching' sound that eminates from the speaker due to intermittent contact between the pot's wiper and its resistance windings. Essentially, the ohmic contact is no longer uniform and the radio's amplifier is getting 'mixed mode' instructions as to what level of output it should be tracking.

If that's the problem (you verify by slowly turning the volume knob once the radio is warmed up and observing a 'crackling' noise here/there across the pot's dynamic range), then shooting contact cleaner onto the pot IS the fix...

If there's something else wrong (say, an amplifier stage coupling capacitor with high leakage that's allowing excessive DC coupling), cleaning the volume pot won't cure the problem...

[Bill I.]

Re: C2 Am/fm Radio Noise

DO NOT use oil, it is an electrical conductor. Bill.

[Wayne M.]

Re: C2 Am/fm Radio Noise

...If that doesn't work remove the side radio panels and try to remove the radio from the car. I never could get it all the way out but did get enough clearance to get a good shot of contact cleaner into the tuner from some of the open holes on the case.
No more pop when I touched the volume knob...

If the decision is to remove, these instructions from the 1967 Delco Radio Manual might help. I've found removal easier when the shifter console is removed, or at least slid back until the side rails are out of the way.

[Stuart F.]

Re: C2 Am/fm Radio Noise

Wayne;

Thanks for posting the radio removal instruction. As a retired tech writer from GM, I automatically try to do everything I can first. And then, if everything fails, I read the instructions. I'm just like everyone else. As I recall with my 63, you really need to get EVERYTHING out of the way - just about like it says. Perhaps it is more difficult on a 67, I don't know, but I've had radios in and out of my 63 enough times to have stripped some of the screws - specially on the heater ducts. I had to fix some of those with clip nuts like they should have been in the first place! Tapping into fiberglass! you have to be kidding!

Stu Fox