1973 Convertible Top - What is this Cable??

[David C.]

I discovered a broken cable on my 1973 convertible which goes from where the convertible frame mounts on the car to the rear bow, on the driver's side only. The cable is approximately 9 in long with a ring connector at each end. I am convinced it looks and is built like a grounding cable. I could not find it in my 1973 AIM. However, I did find out that there is apparently a "bow stay cable" on 73 - 75 convertibles. It is not indicated for other year C3 convertibles. I ordered one from Corvette Central and, although the length is right, the connectors and the cable itself are much too small and won't work. I have attached a picture of the original heavy cable (broken) and the one I bought in the bag. You can see the difference

Does anyone know 1) what the purpose of this cable is, and 2) where I might get a proper replacement or 3) how to reattach the old one?


Many thanks.
Dave

IMG_2212 [150436].jpg

[Joe L.]

Re: 1973 Convertible Top - What is this Cable??

I discovered a broken cable on my 1973 convertible which goes from where the convertible frame mounts on the car to the rear bow, on the driver's side only. The cable is approximately 9 in long with a ring connector at each end. I am convinced it looks and is built like a grounding cable. I could not find it in my 1973 AIM. However, I did find out that there is apparently a "bow stay cable" on 73 - 75 convertibles. It is not indicated for other year C3 convertibles. I ordered one from Corvette Central and, although the length is right, the connectors and the cable itself are much too small and won't work. I have attached a picture of the original heavy cable (broken) and the one I bought in the bag. You can see the difference

Does anyone know 1) what the purpose of this cable is, and 2) where I might get a proper replacement or 3) how to reattach the old one?


Many thanks.
Dave

[ATTACH=CONFIG]68493[/ATTACH]

Dave------


It's a GM #3977787 cable used for 1973-75, although I think it might also have been used earlier.

The cable you were sold might be a reproduction of the GM #3942763 or 3942764 used for 1968-70 and, possibly, later. Are you sure it won't work? If it's just a matter of the thickness of the cable ends, that should not matter too much.

[Jimmy P.]

Re: 1973 Convertible Top - What is this Cable??

Dave,
Those are essential for lifting and stowing the convertible top. I believe there should be springs attached to them too. I'll check mine on my 73 when I get a chance to see. If you take a look at Dr. Rebuild's site, you will be able to see the springs. But his cables are repros too, and the ends look similar to yours from CC.

[David C.]

Re: 1973 Convertible Top - What is this Cable??

Thank you Joe.
The problem is that the hole in the repro ring connector is too small for the original bolts. I suppose the holes could be enlarged but there is not much metal on the new connectors. Certainly the cable and connectors are not nearly as heavy.

Do you know what this cable was used for, what is its purpose? It is only on one side (driver's), and has nothing else besides attaching via screws to the rear bow and convertible frame mounting bracket. It may limit how far the rear bow can be folded, but am not sure why that is necessary. The top appears to function fine.

[David C.]

Re: 1973 Convertible Top - What is this Cable??

Thanks for responding Jimmy. I think you may be referring to the tension cables. This one is different, it seems only to limit how far the rear bow can be folded. It looks a lot like a heavy ground strap cable actually.

If you can see a cable on the driver's side of your car, going from where the rear bow attaches to the top frame, down to where the frame mounts to the car, then that would be it.

[Joe L.]

Re: 1973 Convertible Top - What is this Cable??

All------


I did a little more research on this and it turns out it's kind of interesting. The GM #3942763 and 3942764 cables were used for all 1968-75 convertible top assemblies. These are the "cables with the spring on one end". For the 1973-75 model years, the GM #3977787 was apparently added to the left side only as described above. However, the 3977787 is a 1970 released part. I have also confirmed that it was first available in SERVICE in 1970 but it was never cataloged for a Corvette application until the 1973 model year. So, the mystery is why did it take 3 years for it to be used in PRODUCTION? It's, of course, possible, that it was used earlier for some other Chevrolet application but no other Chevrolet application had a convertible top anything like a Corvette.

The only thing I can think of is that this cable was originally released in 1970 as a RETROFIT to cure some problem some folks had with 68+ convertible tops and was installed by dealers to satisfy owners experiencing whatever the problem was. Then, for 1973, GM elected to install it in PRODUCTION for all Corvette convertible tops.

[Jimmy P.]

Re: 1973 Convertible Top - What is this Cable??

Joe,
Thanks for all the extra research. Very interesting to me.
Here are some photos of the cable from my 73. The first photo is where the cable is attached to the top left corner of the frame. The middle photo shows the path the cable takes. The third is where the cable attaches at the bottom rear of the hinge. From what I can tell when you lift the back of the top up it stops the rear of the top from going too far. It keeps that first fold with the back window just right. So, perhaps before the cable the top would fold up too far.
Dave, your right about other cables with the springs were for tension, hope this helps clarify some things for you too. I think you are correct in your assumption of what the purpose of the cable is.
Hey, just another interesting fact for the 73.
Regards,
Jim

[David C.]

Re: 1973 Convertible Top - What is this Cable??

Joe, Jimmy, thank you both.
It certainly appears plausible that this cable was added along the way to solve some issue with how far the rear bow can fold. Although I am not sure what that issue might be.

In any case, I would still like to find either a suitable replacement or fix my original.
Any ideas?