Mr Fufu

My '67 small block has the RC-26 radiator cap. Here's a photo of the original radiator cap the car came with:



I bought a repro RC-26 cap from Paragon to replace my original cap which is stained or corroded with some black substance which wouldn't wipe off. However, I'm not happy with the Paragon repro cap which is a rather shabby reproduction - the lettering on it is much fainter than on my original cap, and the cap surface itself is kind of wavy, not flat and smooth as on my original cap. So here are my questions:

1. Is my old stained cap the correct type and design? Didn't the OEM RC-26 caps have raised letters saying "NEVER OPEN HOT"? What did the original RC-26 caps look like?

2. If I want to clean and renew my old cap, how do I do it? Is there a way to clean that black crud off? Should I use some type of polish?

Thanks for your help.

teneck83

Send it to Joe Perri to restore.
312-307-1977

ricks327

Here is my 67 repo cap that I bought from Dewitt's a number of years ago.
Rick

Powershift

I agree...........Joe did my RC-26 cap a year or so ago and it is both beautiful and functional......although not cheap

There are a few variations of the RC-26 cap with the markings and logo on opposite sides. Yours agrees with the NCRS 1967 Judging Manual.

You could probably use a buffing wheel and some buffing compound to smooth out the finish and remove some imperfections. Then coat with Eastwood Diamond Clear Satin.

Larry

Powershift

Beautiful reproduction. I bought one like this a few years ago from LICS and then tested it with a Stant Tester. It took 21 psig to open. I did NOT install it on the car. Sent original to Joe Perri for restoration, and now all is well.

Larry

bill3302

Just got back from Joe Perry @ Gen4. Did a Great job!

Mr Fufu

Yes, that's a really nice repro cap.

I'll try to polish up my original on a buffing wheel using some aluminum polish as it looks much better than the crappy repro that Paragon just sold me.

65hihp

the cap you are showing in the first post is a repro, not an original. Certainly don't send that to Joe P for restoration. Just clean it up a little if you wish, but the black is where the plating has deteriorated and will soon return.

Powershift

That is what I thought also, but I could not be certain so I accepted his word. It looks pretty good, but the engraving and a few fonts don't look like OEM originals I have seen. But pictures can be deceiving.

Larry

65hihp

It's the same cap as Ricks Dewittes repro.
the origies are quite different in how the markings are rolled into the metal vs being lazer etched in,
and in the faint flared edges on the wings.
clearly seen in Bill's origie. If turned over there is no doubt.

Mr Fufu

Thanks for that. No, I won't be spending any $ to have this cap restored, esp. since it is a repro. But, how can you tell the cap is a repro? Perhaps you can post a picture of an original for comparison?

Cheers, Alex

65hihp

Alex
I don't have an original RC26 to show you, but do have a couple 307 13# caps that look like what Bil3302 is showing above. But no photos at the moment. The markings are rolled into the cap metal which deforms the metal on the originals, rather than etched in which makes for a finer more precise imprinting. But the most obvious difference is on the inside where you see the cup on Bill's cap inside vs a thin flat disc on your and all repros. The repros are prone to fail whereas the old original AC caps are far less likely to come apart and fail.