C2 ground straps

[Gary B.]

[Tom D.]

Re: C2 ground straps

How about an excel spreadsheet? (and a young son or daughter who has time to populate it for you).

Here's one example of several parts I bought in the seventies, thinking they were the same as OEM parts. I learned later... that was not the case. OEM not same as NOS!

For comparison, Part number 2972627 (from Parts Group number 2.3421) has internal teeth, and non-circular ends.

NOS ground strap 2972627 - 1.jpg

[Gary B.]

Re: C2 ground straps

Tom,

What is the application for GM

[Tom D.]

Re: C2 ground straps

Gary: I guess Not in AIM due to being a service part.

I see Rowley has 6287260 for sale from the same group, and calls it the accelerator ground strap. It looks longer than GM 2972627, which I think I bought for the same application (bought 12, and have 11 left if you want one). Had them for a long time, prob. since 1974.

Overall length of GM 2972627 is 6.25". That's a little longer than most parts in kit number VGS6466WO (LL) sold by Paragon as 1657K. I just wanted to show the internal teeth in this one. (The one from Rowley only has teeth on one end.)

Additionally, I noted a listing from the 1967 parts book when I searched for 2.341. Can't seem to find that back, but it was interesting. Didn't help much with the application list for ground straps in that group. I did note that battery cables were in the same group.

Try google for "2.342 group parts list" or something like that. http://toms427impala.info/CT/72PA/1972-PandA.pdf looks to be the very beginning of a parts book. What ai found before was also from http://toms427impala.info. THANKS FOR YOUR THREAD BY THE WAY, as I am just about to add the straps on 1965 A O Smith Coupe.

[Gary B.]

Re: C2 ground straps

Tom,

These are the part numbers for the copper braided ground straps in the ‘66 AIM:

GM 2981859; Qty=2; center exhaust clamps to frame
GM 2981856; Qty=1; engine mount to frame
GM 2981858; Qty=1; accelerator lever
GM 2982782; Qty=1; body mount to birdcage

Gary

[Gary B.]

Re: C2 ground straps

?..

Overall length of GM 2972627 is 6.25". That's a little longer than most parts in kit number VGS6466WO (LL) sold by Paragon as 1657K...

[Tom D.]

Re: C2 ground straps

Tom,

These are the part numbers for the copper braided ground straps in the ‘66 AIM:

GM 2981859; Qty=2; center exhaust clamps to frame
GM 2981856; Qty=1; engine mount to frame
GM 2981858; Qty=1; accelerator lever
GM 2982782; Qty=1; body mount to birdcage

Gary

ALSO: For what it is worth: Found this in my box of (Storage box #385, with mostly repros.) extra straps.
It might be from LICS. The paper I photographed is small and green. Thanks again for this discussion.

green sheet pn listing for Gary B. - 1.jpg

[Gary B.]

Re: C2 ground straps

ALSO: For what it is worth: Found this in my box of (Storage box #385, with mostly repros.) extra straps.
It might be from LICS. The paper I photographed is small and green. Thanks again for this discussion.

[Richard M.]

Re: C2 ground straps

Tom,

What is the application for GM

Wiki says it for multiple locations from 1956 to 1971 in the 1979 P&A

http://www.gmpartswiki.com/getpage?pageid=99446

along with other makers like Olds for grounds to various places.

http://www.gmpartswiki.com/getpage?pageid=43422

In Nov 1975 2982782 was replaced with 2972627. 2981858 accel strap on that page also went to it.

http://www.gmpartswiki.com/getpage?pageid=23155

It appears that a generic multi-use new strap replaced both the original body strap and the accelerator lever strap.

[Ronald L.]

Re: C2 ground straps

Gary - I'm not so sure that is how the GM Licensed Program works. First those prints would need to be in the system and for the most part, ten years ago they were not.

Rick,

Thanks for checking. Unlike you, I have no original examples or access to Bowtie cars to check. My only thought is what I said above. Braided copper is readily available in larger widths than what LIC uses in their repro strap kit. For the most part, I think LIC does a decent job at getting these things right, so I tend to think their accelerator strap is the width that GM spec’ed. I know that amounts to a big wish. I believe there are examples of LIC paying GM a repro license fee to have access to GM engineering drawings when making repro parts. I’d like to think their accelerator strap is accurate based on what LIC has seen from GM.

Gary

[Tom D.]

Re: C2 ground straps

I think 2982782 has a "slide on flag clip" on one end. (Third one down on Gary's first photo up top.)

If 2972627 was intended to replace it, you would have to drill a hole in the birdcage. I am not at all surprised by this, but I wonder how many times the mechanic did that... Wonder if anyone would notice if I did that...


P. S. There is no evidence of a motor mount to frame strap ever being installed on my '65 project.

[Gary B.]

Re: C2 ground straps

Tom,

I have the original screw and star washer from the motor mount to frame ground strap, but not the actual ground strap, from when I dismantled my ‘66. In fact, I have three identical star washers (left in my photo) from my ground straps. They all have 8 squared off external teeth, unlike the repros from LIC which are larger and have both external and internal teeth.

The two larger star washers on the right in my photo came from my power antenna ground strap, and 2nd location that I did not document adequately. The seven LIC repro star washers that come in their kit are reasonably similar to the washers at the right in my photo.

Gary
615EA8FD-EA58-469C-B9F7-4E3CA2EC56DE.jpg

[Tom D.]

Re: C2 ground straps

Here are the remains of the left side exhaust ground strap on my '65 project. The washer on the right side was smaller, both original per my analysis.

remains of exhaust ground strap - 1.jpg

[Gary B.]

Re: C2 ground straps

Tom,

That looks like a 12 pointer (but the points are squared off, until the LIC repros). Any idea if there are internal teeth as well?

The ‘65 and the ‘66 AIM list two star washers for the radio ground straps. The parts numbers are 121753 and 174916. The 12173 is the smaller of the two, with only external teeth, probably 8 or 10. The 174916 is larger and has both internal and external teeth. The AIM calls out only the smaller for the exhaust clamp to frame location. But you can imagine the production line workers with two bins of star washers for the radio ground straps grabbing whatever was closest.

Gary

Gary

[Tom D.]

Re: C2 ground straps

Tom,

That looks like a 12 pointer (but the points are squared off, until the LIC repros). Any idea if there are internal teeth as well?

Gary

Yes. Looks like your larger ones in the photo above.