C2 Big Block Oil Cap

[Robert K.]

Did some searching around in the archives tonight but was unable to locate information on the following:

I recall reading an article (within the past 6 months, I think) as it relates to C2 big block oil caps and the fact that this oil cap was used on other (non-Corvette) GM applications and (if lucky) could be located in a slavage yard.......!! I believe that this is the cap with the "S" on the top center and it has a "parkarized" (check that spelling....!!) finish......

Anyone recall seeing any words like that?

Thanks for your help........

Bob

[Gary C.]

Re: C2 Big Block Oil Cap

moved your post to the Technical Forum. Gary....

[Robert G.]

Re: C2 Big Block Oil Cap

I did much searching in junkyards 25 years ago and I found caps with the 'S', but they were all orange. Even if you do find a cap, which is even more unlikely today, it will leak oil since the gasket is so old. If the repros pass judging scrutiny, go with that.

[Lawrence S.]

Re: C2 Big Block Oil Cap

If I am not mistaken, you need one with "SMC" stamped on the cap on the body of the cap. Yes you need the S on the rivet for Stant. I have seen them on EBay for $250.

[Terry M.]

Re: C2 Big Block Oil Cap

If I am not mistaken, you need one with "SMC" stamped on the cap on the body of the cap. Yes you need the S on the rivet for Stant. I have seen them on EBay for $250.

I have always wondered why a company would put their logo on an item twice. SMC = Stant Manufacturing Company where as the S = Stant. Those logos might be from different times or even from a time when the company was in the process of changing their corporate identity.

It is the reason the reproduction that is so commonly available has both logos on it -- although the S on the rivet is etched rather than stamped.

It seems strange to me that chrome C3 oil filler caps have only the S logo on them. BWTFDIK.

For your reading enjoyment:

http://www.stant.com/brochure.cfm?brochure=231&location_id=119

[Ronald L.]

Re: C2 Big Block Oil Cap

For the C2 big blocks, there were more that just the SMC, the S, the repro is so different it is very very obvious.

I thought we had a good bit of detail on this subject earlier this year, but the wings you can see differences as well as differences in the underside of the rivet. The finish is black oxide.

Black Oxide is NOT parkerizing which is phosphate coating. The big buyer beware is that most 'restored' caps are fudge painted.

There have been attempts at turning orange caps into black oxide finishes but so that that has not been too succesful.

[Robert K.]

Re: C2 Big Block Oil Cap

Ron,

Are you quite sure about the "black oxide" vs. the parkarizing finish. This is the first that I've heard of "black oxide"........I'm always willing to learn tho'!!

Do you know how the black oxide finish was applied? Is it a baked on process, chemical finishing process, etc?

Bob

p.s.
Also, don't know if you had a chance to read this entire thread, but I am still looking for any information related to other GM line products that used the same cap. As noted in the start of my thread, I thought that I recall some information on this a while back.........?

[Ronald L.]

Re: C2 Big Block Oil Cap

Robert, Very sure. Been there and done that at GM materials.

And...

Looks like I started the thread on caps early this year!

https://www.forums.ncrs.org/showthread.php?t=7555

So from that thread, since then, what I have are some originals that have black oxide on both side of the metal. I have spoken to companies that do black oxide and Stant. Its very interesting the largest cap maker and the largest black oxide shop (in the day) are in the same town - how does that work?

Forget about the paint if you want exactly original.

Second best are the repro parts that were made a while back,
three issues,

the die that stamps the metal was tuned so all the edges are not the same, the rivet is wrong, and the metal form is too tall. It is black oxide however.

I have all these, some pictures were in the post. As were that some try to get close with a paint approach.

No offense, but paint is not black oxide. The chrome and orange caps were run off a different die. the edges have a different shape and its a real bugger to get the orange out from underneath the rivet - a bang and opps! plus, the back side will not be black oxide.

[Bill M.]

Re: C2 Big Block Oil Cap

p.s.
Also, don't know if you had a chance to read this entire thread, but I am still looking for any information related to other GM line products that used the same cap. As noted in the start of my thread, I thought that I recall some information on this a while back.........?

I have a '67 L78 out of a Camaro that has the black cap.

[Ronald L.]

Re: C2 Big Block Oil Cap

Engie plant installed, should find same part on same-spec'd motors.

[Wayne M.]

Re: C2 Big Block Oil Cap

.....Looks like I started the thread on caps early this year!
https://www.forums.ncrs.org/showthread.php?t=7555
.

Ron -- could you recheck the above link ? I'm getting a 2002 thread on trim rings .

[Ronald L.]

Re: C2 Big Block Oil Cap

Maybe we have to have the entire URL?

https://www.forums.ncrs.org/showthre...75558&uid=2420

Jan 20 of this year...