1970-72 dual snorkel air cleaner wing nut

[Patrick H.]

Hi All,

Can anyone tell me the difference between an original and a reproduction wing nut for the air cleaner cover? I believe that I have one of each for my 71, and a "real" one for my 72, but do you think I can tell the difference? No.

If anyone has pictures, I'd be happy to look at those too.

Thanks,

Patrick

[Patrick H.]

Photos

A fellow member was kind enough to provide me with a picture of the two wing nuts. He believes that the lower one which appears thicker is correct.

Can anyone else confirm this?

Thanks,

Patrick




Comparison Photos

[Joe L.]

Re: Photos

Patrick------

The lower wing nut in the photograph appears like the correct GM #219281 nut. One might be able to take the upper nut and modify it in a vice to be close to the original configuration. I don't know if that's illegal or, at the very least, unethical, though.

[Gerard Q.]

Re: Photos

For what it's worth, the wing nut on my restored 71 looks like the lower one in the photograph.

[Jack Corso]

Re: Photos

The lower wing nut looks like a Paragon reproduction. I believe that the top one is correct. I have removed two wing nuts from early 70's GM vehicles and they do look like the top example. (I went through this when I Top Flight'ed my 71 LT-1) in 2001.

[Robert C.]

Re: Photos

That photo is a bad example. I believe both wing nuts in the pictue are repro's,one with the ears pinched in. Original nuts are shaped like the top one but thinner. Originals are 'dime' thick. Repro's are 'nickel' thick.

[Patrick H.]

Re: Photos

Bob,

I knew you had discussed this before. Might you have any pictures?

Thanks,

Patrick

[Joe L.]

Re: Photos

Bob-----

I have an absolutely, positively, guaranteed-to-be-original example on my 69. It appears very much like the LOWER wing nut in the picture and nothing, at all, like the upper wing nut. The ear on right side of the lower wing nut does appear to be "pinched in" just a bit more than my original wing nut, but I'm sure that these pieces were not precision-stamped so there may have been some slight variations.

Also, the thickness of the material from which my wing nut was manufactured is very close to 0.065". This is very close to the thickness of a nickel and considerably thicker than a dime.

[Robert C.]

Re: Photos

Joe I'm sure you're wing nut is original, but, these originals like radiator caps are VERY hard to find. If you view the original thinner wingnut next to the thick repro, you can easily see the difference. The picture on this thread looks like two thick ones to me. The dime thickness has always been the rule. There is no current repro that is like the original. 80% of the cars I judge have the repro wingnut.

[Terry M.]

Re: 1970-72 dual snorkel air cleaner wing nut *TL*

I notice Partick's original question is about dual snorkel air cleaner wing nuts. Joe's 1969 and my 1970 are open element air cleaners. Could it be that there is a different nut for the different configurations?
I have sent Patrick a photo of the wing nut from my car. It looks to me like the dime thickness, but when Patrick posts it, you can judge for yourself. There may indeed be more configurations of these than we at first thought.

[Patrick H.]

Terry's Wing Nut

Click below for a photo of Terry's wing nut.

I think he may be on to something.

I would not be whatsoever surprised to find out that the open element air cleaner and closed dual snorkel unit came from different suppliers. As a result, should we be surprised if they actually have different wing nuts? Never thought of that one before, did you?

Anyway, I found the original wing nut that came on my 71. I will be visiting all my cars on Saturday, and taking photos of various wing nuts to share. If anyone else has photos of KNOWN ORIGINAL wing nuts from their cars, ESPECIALLY dual snorkel cars, I can add them to what we have here.

Thanks,

Patrick




Terry's Wing Nut

[Calvin M.]

Re: Terry's Wing Nut

Hi All -
I'm looking at an original wing nut from a dual snorkel '72. (But have no way to photograph it now.)
It matches the top nut in Patrick's photo and Terry's wing nut. The thickness is much closer to a dime than a nickle, and the space between the sides of the wings is too wide to "hug" a nickle.
Cal

[Jack H.]

Hum....

Looking at my '71 AIM, the base engine air cleaner (closed) wing nut is PN 219271. The LT1 option doesn't appear to define a different wing nut and the LS5 engine depicts a wing nut but doesn't call out a specific PN. The LS6 engine option (open air cleaner) depicts the wing nut with caption 'Prod Nut' implying it's the same PN as the base engine.

One 'correct' method for researching this would be to gather similar PN info on other early Shark years from the AIM's and see if there's any other wing nut PN references. Then, pull the GM drawings on the part(s). If these were purchased parts (highly suspect these fasteners were purchased), there should be a block on the drawings that points to a separate purchasing spec. This could be a list of qualified vendors, their part numbers for the item and contact info. Art Armstrong could tell us a LOT more about the documentation audit trail GM used in the drawing system....

Bottom line, my hunch is there were several vendors qualified to supply this lowly part, they changed over time based on price/delivery/performance. And, eventhough there may have been n-tuple vendors qualified to source a given part, certain final assy plants may not have stocked their bins with parts from one or more of the qualified vendors due to freight-in cost considerations, Etc.

In researching and improving on our judging text/standards, it would SURE be useful to have access to the GM drawing system (even if we paid a reasonable fee for dwg reproduction and mailing). Such 'could' be administered through a neutral 3rd party, like the National Corvette Museum, and perhaps generate a modest revenue stream.

I suspect those who participate in GM's Licensed Reproduction Program as for-profit parts suppliers DO have GM drawing system access.... To what degree, and under what cost silhouette, I don't know. But, it seems that we who judge the cars and write/control the judging standards suffer an 'information gap' that results in old wife's tales about this/that part and we could IMPROVE ourselves if we had equivalent drawing system access.

[Joe L.]

Re: Terry's Wing Nut

Patrick-----

My original wing nut is identical to Terry's wing nut. To my eyes, this wing nut is CLOSER in configuration to the one on the bottom of the original photograph you posted. The ears on that nut may be a little tighter than the original nuts, though. The ears on the top wing nut in the original photo look MUCH wider than the original wing nuts.

Also, I think that if one were to measure the thickness of the material on the original wing nuts, one would find that it is much closer to the thickness of a nickel than a dime. I get about .065" for the original wing nut. A nickel, at the edge, is about .069"; a dime, at the edge, is about .045".

As far as I know, wing nuts of the same part number were used for all 65-72 Chevrolet chrome air cleaner applications. As Jack pointed out, these wing nuts were almost certainly manufactured by several different suppliers using different tooling. So, there will likely be slight differences among "original" wing nuts.

[Roberto L.]

Re: Hum....

Hello, in the 70 AIM the wing nut is 219281. 70 AIM shows later type engine air cleaner with dual snorkel, but I got from you (Jack Humphrey), if I'm correct, a 69 AIM page with open type air cleaner (which was used in the early 70 air cleaners) and it shows same number, 219281.

Optional engines drawings read 'production nut' implying those engines use, apparently, the same wing nut.

Roberto, NCRS #30019, RMC