C3 (72) Cotter pins

[Rob C.]

Hello again,
I was told that I have the wrong cotter pins in some of my suspension parts.
I did not get a chance to ask the juge wich was the right ones. Could some one post a picture of one so I know what to look for. I thought I had some good picturs of a 71 but I do not.
Thank you,
Rob

[Chuck S.]

Re: C3 (72) Cotter pins

For suspension items, I doubt it was the cotter pins themselves...it may have been (1) finish (originals were natural; virtually everything you find today is zinc plated), or (2) the configuration of the spreading/bending (there is a specific way it was done at St Louis).

It was probably on the lower ball joint cotters...those cotter pins were done a specific way to avoid interference with the plant alignment equipment. See your AIM; in the 70 AIM this detail is shown on UPC 3, page A3, View A note.

[Rob C.]

Re: C3 (72) Cotter pins

Thank you Chuck,
The configuration is right. It must be the plating.
Thanks Rob

[Greg L.]

Re: C3 (72) Cotter pins

Is there not a remarks column on the judging sheet that says what the deduct was for?

[Peter L.]

Re: C3 (72) Cotter pin plating

Rob - Most if not all "standard" cotter pins are zinc plated and that's what the ones used on your 72 were in 1971 or 1972. Pete

[Joe L.]

Re: C3 (72) Cotter pin plating

Pete-----

I think it's the other way around, at least for the cotter pins that GM used. Most of the cotter pins used by GM were of "plain" finish. All of those used for the rear suspension on Corvettes from 1963 through 1982 were "plain". I'm not 100% sure about the ones used for the ball joints, but I'm about 95% sure that they were plain.

One can still purchase "plain" cotter pins. I don't use them, though. NEVER. I use only zinc plated or stainless steel cotter pins.

[Peter L.]

Re: C3 (72) Cotter pin plating

Joe - Not quite sure what a "plain" finish is but my experience from cotter pins removed from unrestored cars is that the finsh is zinc on the steel. Pete

[Harmon C.]

Re: C3 (72) Cotter pin plating

Pete
Plain is natural steel cotter pins and is what I find on original shark cars suspension.

Lyle

[Terry M.]

Re: C3 (72) Cotter pin plating

Not to throw (*&# in the game, but I have found a mix of plated and unplated cotters on the original cars I have examined -- mostly early C3 Corvettes.

[Joe L.]

Re: C3 (72) Cotter pin plating

Pete-----

The GM specifications for the vast majority of cotter pins used on 63-82 Corvettes calls for a "plain" finish. In GM parlance, "plain" refers to a natural, un-plated steel finish. It's always possible that substitute parts could have been used in PRODUCTION. However, I would expect that, typically, parts of the specified part number and, consequently, specification would be used.

My experience with my 1969 is also that original cotter pins were generally plain. There were a few exceptions, though. Some of the real small ones (like, the ones used for the reverse lock-out cable connections) were plated.

[Harmon C.]

Re: C3 (72) Cotter pin plating

Terry

Their must be a judge out their that has decided what the cotterpins should look like and how they are bent. The first poster should ask the judge the next time he sees him what he wants to see.
Lyle

[Terry M.]

C3 (72) Cotter pin judging

Gee, I wonder who that judge might be?

I will pass on what is most often talked about in the Advanced Judging Schools -- Be sure to get the right direction on the cotters at the rear lower shock mounts (top to bottom – the frame was built upside down). That is the easiest for the judges to spot. One should probably put the cotter pin into the front trailing arm bolt upside down as well for the same reasons as the rear lower shock mount. Then be sure to get the UPPER ball joint cotter bent against the nut for earlier than 1972 (see your AIM for note on this cotter).

I have yet to hear a discussion of plated or unplated cotters in the school, but if you feel strongly about natural finish -- a little bird told me the zinc plate can be removed by soaking the cotters in neat lemon juice.

There are instructions on how to bend cotter pins in the front of each of the AIMS. If you believe the plant workers followed those instructions (and if you do, I have a bridge for you), you are well advised to follow them also. If you are removing your original cotter pins, follow what is there -- you should be able to see some plate on the part of the cotter that is inside the stud, if they were originally plated.

All that said, I don't see how one can lose more than a couple of points at the most for the cotter pins.

[Terry M.]

Addendum

Rats -- no editing

Cotters in the lower rear shock mounts should be bottom to top -- that is upside down from the way the frame is when the car is greasy side down.

[Chuck S.]

Re: C3 (72) Cotter pin judging

"Gee, I wonder who that judge might be? "

And, if you told him, you'd have to kill him?

I just don't know...we have what I consider some of the smartest Corvette people available here, and we can't even agree on whether the cotter pins should be zinc plated or not. I can see how a new member taking his fresh restoration from meet to meet trying to Top Flight could get pretty frustrated.

P.S. Agree with you on the AIM general instructions...no one would spead cotter pins like that (minimum 45 degrees from centerline each side.)

[Peter L.]

Re: C3 (72) Cotter pin plating

Thanks Joe - It is what it is, although I'm sticking with the zinc plated ones for my projects. Don't want corroded cotter pins to worry about. Pete