Anyone ever replaced the antenna and cable on a '72 coupe?

[Roger D.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Lyle:

Thanks to Gary, I know the correct cable length is 177 inches. I found one on Corvette Central for $28. You're right. I'd much rather get the right cable and install it correctly.

Now everyone, how about that grommet? (see previous posts above)

Roger

[Terry M.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Terry, guess I missed that splice when I judged your car. But then we don't lift the carpet, do we?

If you would have looked for a rear window defogger you might have found it, but since I don't have the RWD there is no reason to look. I will show you if I bring the car to the Novi National. I am working on the logistics of that already, but there is a lot of work involved. I am not sure I want to wait for the 2020 Convention when it will be the year of the 1970.

It has been years since I used this, but it seems appropriate to mention it now:

There are several ways to get all the points. One can do the restoration perfectly. One can fool the judges. And one can distract the judges. Take your choice.

[Paul O.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Roger if you are going to Carlisle I have a an original cable out of a 71. I am at J-50 ask for Paul radio worked normal before car was totaled. As for the Grommet there are a few products out there to help. I think Terry listed the product if I remember it was something 303 you could find it in the archives under rubber protector. When installing the new cable a light coating of silicone grease would help with the install thru the grommet.

Paul 18046

[Terry M.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Roger if you are going to Carlisle I have a an original cable out of a 71. I am at J-50 ask for Paul radio worked normal before car was totaled. As for the Grommet there are a few products out there to help. I think Terry listed the product if I remember it was something 303 you could find it in the archives under rubber protector. When installing the new cable a light coating of silicone grease would help with the install thru the grommet.

Paul 18046

Aerospace 303. A good vinyl and weather strip treatment. Available at boating supply stores, some True Value (IIRC) Hardware stores, and of course the Internet. Not inexpensive, but it works and is not greasy.

[Roger D.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Paul, Terry thanks for the response. I ordered the 177" antenna cable from Corvette Central. I have the existing cable exposed the whole way. I tied a string to the end of the old cable and pulled it back thru the dash and the end is hanging down from the driver's side of the dashboard. It was hard enough to pull the old one out thus I don't believe it will be possible to pull the new one into place with the string. I think I may have to re-route it otherwise would have to pull the rest of the dash out.

Anyone else have a problem getting the new antenna cable pulled back thru where the old one was?

Roger

[Jack H.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

It helps to pull the driver's seat (only four bolts) so you can lay on your back on the cockpit floor and CAREFULLY sniggle/wiggle the lead-in cable across the dash from the underside.

Plus, when it come to the grommet in the rear wall, popping the rubber out so you gain full access to the routing hole helps a bunch. It's when we take 'short cuts' and pull/bend the antenna cable that (*&^ happens!

[Roger D.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Had a little snafu with my parts order so I am still waiting on them.

Jack, Corvette seat out. Still don't see how it is possible to get the cable thru, especially considering it comes with a 90 degree bend in the end connector (radio end). It had some considerable resistance just pulling the old one out thru the passage there behind the dash. Oh well, I'll figure something out.

[Jack H.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Which way are you threading the lead-in cable through the dash? You can go from the radio to the antenna at the rear of the car or do it the hard way going from the antenna to the radio...

[Robert S.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

I replaced the antenna cable on my 74' convertible this spring. I assume yours would be essentially the same task. At this point I am not sure if my new cable is defective or not so task one is to take the new 177 inch cable (I got mine from Paragon and it was exactly the same length as the original I removed) and connect it to the radio and the removed antenna mast and be sure the radio works as you think it should on AM and FM. Assuming the cable is good I ran mine from rear to front. I had to drop the exhaust on the drivers side to gain access to the cable at that end. I had to remove the dashpad (which meant I had to remove the dash panel on the passenger side and the interior trim panels going around the inside of the windshield, and I had to remove the sill plate and the drivers side kick panel and I had to remove a plastic panel at the aft end of the drivers side door. Once the old cable was removed I layed the new cable on the floor lengthwise and started to route the cable first through the rubber grommet in the rear panel and then forward following the routing of the old cable. There was no problem getting the cable through this grommet. The total task took me about 2 hours going slowly. The hardest part is getting the cable up vertically in the kick panel area and then across the top of the gauges and then behind the center stack and down to the radio.

[D S.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

I need to replace the entire antenna/cable assembly on a '72 small block coupe. I have the AIM but would like to know a little more of what I am getting into before I start. I'm sure that many have already done this a time or two. Can anyone enlighten me on the "challenges" that lie ahead for me on this little project?


Thanks all in advance.

Regards,
Roger

Roger, don't tell anyone your radio doesn't work. Just kidding. I was lucky to have my interior completely out of my '70 when I ran an original antenna cable through the grommet in the rear bulkhead using silicone to lube the cable. Having personally seen your very nice '72 coupe I would not go to that extreme.

[Roger D.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

I replaced the antenna cable on my 74' convertible this spring. I assume yours would be essentially the same task. At this point I am not sure if my new cable is defective or not so task one is to take the new 177 inch cable (I got mine from Paragon and it was exactly the same length as the original I removed) and connect it to the radio and the removed antenna mast and be sure the radio works as you think it should on AM and FM. Assuming the cable is good I ran mine from rear to front. I had to drop the exhaust on the drivers side to gain access to the cable at that end. I had to remove the dashpad (which meant I had to remove the dash panel on the passenger side and the interior trim panels going around the inside of the windshield, and I had to remove the sill plate and the drivers side kick panel and I had to remove a plastic panel at the aft end of the drivers side door. Once the old cable was removed I layed the new cable on the floor lengthwise and started to route the cable first through the rubber grommet in the rear panel and then forward following the routing of the old cable. There was no problem getting the cable through this grommet. The total task took me about 2 hours going slowly. The hardest part is getting the cable up vertically in the kick panel area and then across the top of the gauges and then behind the center stack and down to the radio.

Same method I will use Robert when mine comes in, i.e., starting at rear and going forward. Of course since there was considerable resistance in pulling out the old cable (even without the connector on the end of it) I think it will be even more difficult routing it back behind and over the gauges without rerouting it.

[Roger D.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Hey Scott, everyone...

New antenna cable install is complete. Got car back together about an hour before the car show last Saturday night. However, there's a problem.

I tested the new antenna cable assembly before install by connecting it to the radio. With the cable stretched out and the antenna assembly laying on the garage floor, both AM and FM stations strong. After install, FM stations still strong but I only get a handful of AM stations and they are somewhat weak (it's better than before because I couldn't pick up any AM stations at all then).

Ground plate at base of antenna below deck is in place and ground strap connected to frame. All AM stations come in fine if someone holds onto the antenna with their hand. Also with the antenna removed and a wire with gator clips hooked between the antenna base and the car lift the AM stations come in pretty good.

Any ideas?

Thanks in advance.

[Robert S.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

The problem you are having is exactly the issue I am having with my 74' (referencing my earlier reply) after I replaced my antenna cable. FM and FM stereo is very good, AM works but not as it should be and AM improves if I touch the antenna. My ground plane is also in place. Turning the antenna trimmer had no effect. The only troubleshooting I have done is to change out my antenna mast with one from a friends 75' with no effect. I plan to remove and clean up the ground plane next to see if that will help. I am very interested if you come up with the solution. It would seem improbable that we both have defective antenna cables but I suppose that is possible.

[D S.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

It sounds as if there is not a solid grounding somewhere either via the mast or grounding strap. Lord knows there are enough grounding straps on the C-3s. Try cleaning the frame down to bare metal where the strap attaches and make sure there is a solid ground. I don't recall but is there also a ground wire from the radio to somewhere on the transmission tunnel? The reason I ask that is because my aftermarket radio also gets weak AM stations. I have the original mono AM-FM but I sure don't want to have to pull one out to install another one. Plus I'm looking for a 1970 AM-FM stereo.

[Roger D.]

Re: Anyone ever replaced the antenna and cable on a '72 coupe?

Robert, I'll let you know what I find out if you'll let me know likewise. Don't know about a bad antenna wire. I had two new ones at hand and tried them both prior to installing. As I noted, AM worked fine with both cables stretched out and the antenna assembly laying on the garage floor

Scott, the strap is connected to the plate at the base of the antenna with a small bolt. It does look a little corroded. Also, I wonder that I reached up and was able to touch the plate with my hand and it didn't have the same affect as touching the antenna. If you come across something Scott, give me a call.

Here's hoping someone else had this problem and will see this and relate how they fixed their issue.