Color of PB Check Valve C2

[Larry M.]

Re: Color of PB Check Valve C2

What Michael describes is similar to mine.....chalky white where it has been exposed.

[Larry M.]

Re: Color of PB Check Valve C2

As a follow up, i bought the one from the first picture above on ebay. Actual supplier was Corvette Stainless Steel
Brakes, Miami, Fl. I looked on their direct web site but did not see the part for sale. The color is close to the pic, not quite as yellow or as shiny. I don't think the color is due to pigment but I can't be sure. I'm guessing (and that means guessing) that the material used is fiber reinforced leading to a darker appearance than un-reinforced nylon. There are subtle grain lines in the material leading me to that conclusion. As stated above they also sell one that is very white. The confituration is right and if my original quits I will use it.

[Joe R.]

Re: Color of PB Check Valve C2

As a follow up, i bought the one from the first picture above on ebay. Actual supplier was Corvette Stainless Steel
Brakes, Miami, Fl. I looked on their direct web site but did not see the part for sale. The color is close to the pic, not quite as yellow or as shiny. I don't think the color is due to pigment but I can't be sure. I'm guessing (and that means guessing) that the material used is fiber reinforced leading to a darker appearance than un-reinforced nylon. There are subtle grain lines in the material leading me to that conclusion. As stated above they also sell one that is very white. The confituration is right and if my original quits I will use it.

Hi Larry:

In my earlier post #14 I mentioned that I had recently purchased an inexpensive repro on ebay that looked pretty good except for the color being too white. It turns out that the one I purchased is the white one you mention (a photo of which you showed in post #3), since my receipt is from "C.S.S.B" in Miami, Florida.

I had actually intended to call the seller and tell them I thought their reproduction was pretty good except that the color was too white. From what you are saying, it sounds like they also make this same part in another color that is closer to the off-white nylon color that I think is correct. If I encountered the off-white version in judging I would probably give it full credit, even though I can recognize it as a repro due to certain tooling marks. It’s a pretty good reproduction overall.

For NCRS judging of my '67, I have a genuine original in very good condition that I paid $$ for several years ago when there were not any good repros available. I guess that future restorers will have a more economical choice now.

[Leif A.]

Re: Color of PB Check Valve C2

Joe,
The more off-white check valve from CSSB on my '67.

[Geoff C.]

Re: Color of PB Check Valve C2

Color me skeptical. Here we go again, attributing a part manufactured in the millions as being of done in a particular design for a particular model year.

Story Time: over 40 years ago, circa 1977 I terminated my career as a restorer/rebuilder/replater of 63 and 64-67 Corvette only

[Michael J.]

Re: Color of PB Check Valve C2

Color me skeptical. Here we go again, attributing a part manufactured in the millions as being of done in a particular design for a particular model year.

Story Time: over 40 years ago, circa 1977 I terminated my career as a restorer/rebuilder/replater of 63 and 64-67 Corvette only

OMG! Thank you for all that!

[Leif A.]

Re: Color of PB Check Valve C2

Geoff,

A "spare" that came with my car (quite possibly the original). And, I agree completely with your statement...only seems logical.

[Joe R.]

Re: Color of PB Check Valve C2

Joe,
The more off-white check valve from CSSB on my '67.

Hi Leif:

That color looks pretty good to me. People can argue all day about what color is exactly correct, but this looks close enough to get the benefit of the doubt. I have compared the repro sample that I have (in the whiter color) to some originals that I have collected over the years, and the only obvious difference I can see is that the contours of the funnel-shaped hole in the center are larger and smoother in the originals. Also, in profile, the repro is a bit taller due to a taller "collar" around the top perimeter.

Still, it's a pretty good reproduction. Attached are some comparison photos.

BTW, I tend to agree with Geoff Coenen that it's hard to believe that every '67 Corvette got the style of check valve we are discussing. All I know is that at some point, the '67 team decided this was the correct style for 1967. I think the '66 team now wants to see this style too. My impression is that the judging standard for some other C2 years is less rigid (and the '63 style is completely different anyway).

[Geoff C.]

Re: Color of PB Check Valve C2

There is plenty of evidence there was more than one identical cavity for 64-67 era PB check valves plastic injection mold tooling. Most injection molded parts produced in any large quantity have a cavity number in the different cavities - when there is more than one cavity in the tool. That’s often the easiest way to tell a repro – they have the same cavity number.

On my used selection I have these cavity numbers – 1,2,3,4,5,7,8,9,10,11,12,13,15 plus 80 & 81. Multiples of 81 & other numbers listed also. Some have alphabetic marks: A, AA, C, GHS (is very tiny?), H, K, M, P. Some with a small triangle.

Did you know they come apart? They are not supposed to, but occasionally the do, from age – like you. Don’t know if they were assembled with glue or ultrasonic welding. Note: the round ring on the left broke away from the main plastic part on the right. It is a weak spot, where the plastic is weakened from oxidation? hi temp.? hydrocarbon bath. In any event it is weakened. It is not a separate ring. Just 2 plastic pieces, a rubber diaphragm & a compression spring.

These check valves seldom go bad. My opinion. They are replaced by those seeking better cosmetic appearance. With that said – I think the whitish most corroded ones are the oldest earliest as in 1964 era, and the later ones are a different resin with a different tint. Plus there are different overall designs. When the colors migrated & the different designs arrived is anyone’s guess. It will take much more than an occasional unmolested virgin Corvette with one style or color to convince me that an iron clad rule can be deducted.


I’m done. I’m not going back out to the barn for more old crap.

[Joe R.]

Re: Color of PB Check Valve C2

Here's a couple of pics of valves I have collected. These are original from Corvettes Years (?) but they were collected before repos were important. They have marking similar to what Geoff has described.

JR

[Kenneth B.]

Re: Color of PB Check Valve C2

For those that think plastic doesn't yellow look at a old soft top rear window or white door knobs.

[Larry M.]

Re: Color of PB Check Valve C2

The real color...this just sold on ebay for $788.

[Frank D.]

Re: Color of PB Check Valve C2

Here we go again, attributing a part manufactured in the millions as being of done in a particular design for a particular model year.

Amen.

And nearly $800 for a plastic one-way valve. Not many players at those levels...

[Phillip M.]

Re: Color of PB Check Valve C2

The real color...this just sold on ebay for $788.

Must be NOS because it cost so much!
Phil