'55 Radio Static

Ever since I have owned my 1955 Century I have had static on the radio. It is a loud popping noise. I had the radio rebuilt and they replaced several components but the static is still there. The antenna looks fine and I made sure it was securely plugged into the radio. I am sure the static is ignition-caused since when I turn off the engine the radio comes in loud and clear.

I have replaced the condenser on the generator, and replaced the copper-core wire running from the distributor to the coil with a modern carbon core wire (I think it is carbon). I have not yet installed an in-line noise suppressor but before I spend $30 for one I wanted to check with you folks to see how your cured your radio static and if the in-line suppressor would do the job.

Thanks.

R U sure the antenna cable outer shield is properly grounded?..............Bob

Is the antenna trimmer properly adjusted?

Al

Sorry Bob and Al, I know nothing about antennas except they mount to the fender and plug into the radio. So I don't know what you mean by "trimmer" and I don't know where the "outer shield" is. Please help me with these.

Also, since the radio plays just fine when the engine is turned off, could the antenna still be the issue?

Hi Joe

Sorry I don't have an answer for you on the radio issue.........

I was wondering if you have ever posted photos of your 55 on this forum.

If not I'm sure we would all like to see some .........well I know I would......so how about some nice exterior and interior shots.

The antenna "wire" is a shielded cable. there is a braided copper layer (shield) directly under the outer plastic cover. That braid should be electrically connected to the couplings/connectors on both ends of the cable..............Bob

Bob: I am sure the ends are properly grounded, although I can't really see under the fender. But I assume since the radio plays just fine with the engine off it must be getting the reception it needs. Maybe that's a bad assumption on my part?

Brian: Pictures of the car from the first day of ownership to it being judged at this year's National Buick Meet in Portland, OR can be seen at http://picasaweb.google.com/packick. It has been a long journey but I enjoyed every minute of it. And thanks to the help provided by the folks on this forum I was able to work through the problem areas.

The center conductor in the cable carries the signal from the antenna to the radio. The outer jacket, the grounded shield, shields the inner conductor from ignition noise. The outer shield has nothing to do with "reception". I'm not saying your shield is definately the problem, it may not be, but how the radio plays is not a valid test of the cable's shielding ability. Twer it me my first test would be to take a new antenna and plug it into the radio, ground it to the fender, and see how the radio behaves. If it was the same noise you have at least eliminated an obvious problem point..

BTW. Your shop manual has a section describing how to chase down ignition noise. It also describes "trimming" the radio but that should have no bearing to engine noise.........Bob

Bob, thanks for the advice and explanation of the antenna wire operation. I happen to have another antenna which, when I get time, I will experiment with as you describe.

I didn't know about the shop manual noise debugging section either. Thanks again.

Section 11. You are welcome.........Bob

Even a near perfectly functioning antenna will have noise if not extended enough. Ignition noise can get through the same antenna if sparkplug wires are bad or just not completely seated in the distributor cap or on the plugs. Generators and voltage regulators can contribute noise. Maybe if you could give a description of the noise or post a video with sound...

Wilie

i wonder if the car in question has the static collectors installed inside the front wheel bearing dust caps ?, i'm surprise that it has not been mention before now.

charles l. coker

1953 pontiac tech advisor

tech advisor coordinator

poci.

Since he says turning off the engine cures the problem the supposition has been the noise is present with the car at rest..................Bob

Even a near perfectly functioning antenna will have noise if not extended enough.

I concur with this diagnosis. There is a noticeable difference in static even if my antenna is 6-8" down. Full extended gives best retention. And as per the owners manual, don't start the car with the radio on.

That may be a function of the short antenna having reduced signal strength while the ignition noise is intruding at full strength. When the antenna is extended it's signal is able to attenuate the noise.............................Bob

Boy, lots of information here. I will try to answer the questions posed:

1. The antenna is about 1/2 way extended (about 2'). I will try to extend it all the way but driving like that concerns me. That's why it is only 1/2 way extended.

2. Yes, the static collectors are in the front hubs.

3. The spark plug and distributor wires are brand new (about 3K miles on them) and copper cored, and I have checked that they are seated fully. The generator works fine but I have not had it rebuilt. I don't think the voltage regulator is that old but is a Brand X regulator. It was on the car when I bought it with the old one in a box in the trunk so I assume they had problems with the old one and installed a new one.

4. The noise is a loud popping sound. If you have ever been near an electric fence and heard the popping in the radio, that is what it sounds like only much more rapidly. It gets louder when the engine revs are increased, less loud when the engine revs are reduced, and eliminated when the engine is off.

5. Finally, I never start the car with the radio on. My father beat that into me when I was young along with turning off the headlights.

Phew, my brain has now gone to broccoli. Time for an adult beverage.

What about the noise suppression condenser on the ignition coil? You didn't mention that you had replaced that.

Wheelnut:

I have replaced the condenser in the distributor and the condenser on the generator, but I didn't know there was also a condenser on the coil. Where is it located?

Find an old short wave radio guy. You can spot them by the slide rule in their pocket protector. They can slap an oscilloscope on it and find the problem in a couple of minutes.

In the 1990's I had a big Allen automotive test center in my garage. They aren't around much anymore, but a home unit will get the same results.

Bernie

Wheelnut:

I have replaced the condenser in the distributor and the condenser on the generator, but I didn't know there was also a condenser on the coil. Where is it located?

Section 11-2, sec c, para 6

Bob: I am sure the ends are properly grounded, although I can't really see under the fender. But I assume since the radio plays just fine with the engine off it must be getting the reception it needs. Maybe that's a bad assumption on my part?

Brian: Pictures of the car from the first day of ownership to it being judged at this year's National Buick Meet in Portland, OR can be seen at http://picasaweb.google.com/packick. It has been a long journey but I enjoyed every minute of it. And thanks to the help provided by the folks on this forum I was able to work through the problem areas.

Thanks Joe

Great photos and Great job on refurbishing the 55........she is looking very smart now.

I owned an old early fifties chevy that had a lot of heavy static while running, and a supressor plugged into the distributor cap where the coil wire plugged in took care of the problem.

kaycee

Check and see if there is a grounding strap from firewall to hood. If that is not there noise can sneak through the hood and into the antenna.

d2:

I assume the grounding strap is the metal thingie at the rear of the hood with the swinging piece of metal on it?

I did find out, however, that my radio static collectors in the wheel hubs had disintegrated. I think what happened is that when I put on the axle nut after repacking the wheel bearings, I bent over one end of the cotter pin so that it was on the end of the axle. I suspect as the wheel rotated the radio static collectors got hung up on the cotter pin ends and destroyed themselves. I found NOS ones on ebay and am awaiting delivery to see if that solves my static problem.

Those are only going to help with random occasional 'pops' due to discharge of static electricity that builds up on the rolling tires. You already stated that you knew it was engine related. Something change?

Wheelnut, nothing has changed. But I need to get all of the possibilities working properly to identify and correct the problem. Replacing the radio static collectors in the hubs is just one more base covered.

Source of Radio Static Solved . . . I think.

Sometimes solutions to problems fall right into your lap. Per the suggestion of one of my car club friends, I purchased a new rotor designed to reduce static. As I was taking the distributor cap off to install that rotor, I heard a "plink" on the drip pan below. What had happened is as I lifted the cap off, the ball in the center ​inside​

the cap came out. This is where the rotor makes contact with the center of the cap. Also, the contact on the old rotor to the center of the distributor cap was bent off to the side. How this happened I have no idea. So, I suspect every time the rotor rotated with the bent contact and the loose center of the cap it caused the static. At least that's my theory and I am sticking to it.

I backed the car out of the garage after installing the new rotor and a spare cap that I had, tuned in a strong station with the engine running, and there was no static. Once the weather clears I still need to give it a good road test to determine once and for all if that was the source of the static.

Keeping my fingers crossed.

This picture shows the little ball sitting next to the center of the cap, the place where it should reside.

Your car was about to have bigger problems than a staticky radio if your rotor fell apart.

Mike:

It wasn't the rotor that fell apart but the distributor cap. But you're right, disaster was looming.

Joe, now tune in a weak station, that is the ultimate test.

they still have AM radio stations?