Mystery carb or mystery to me

[fouraceswes]

Mystery Schebler DeLuxe Carburetor. I was told this is a prototype carb. Any comments or observations welcome. The pad is not stamped and altho I have bot seen that many of these the choke is a weird one.

[T. Cotten]

It ain't the choke that's weird, Wes!

It appears to be a hybrid with the GX-4 design, which blows what little mind I have left.

Can't wait until I have time to enlarge and study it...

Your photos are sincerely appreciated,

....Cotten

[Rubone]

Early adjustable venturi experiment? And they spelled Maldwyn Jones wrong!

[T. Cotten]

For comparison, Wes,...

Here is the '26-'28 GX-4 and GX-9 "slide" venturi design, which controlled a needle into the main nozzle as well:

GX4SLIDX.jpg

GX4SLIDE.jpg

It appears its slide is a spade shape instead? Does it have a needle? It is remarkable that it was never nickel'd with the rest of the hardware. That, and the barnyard bend instead of a peened knob suggests it was a trial.

The throttle swivel is unique; Everything is pristine, but the bowl is backwards, with a potmetal-vintage bowlnut that would date it after June of '28 or so. Its bowlcap deck appears level with the top of the bowl, associated with Type A DLXs (and 1 1/4" HXs). The bowlcap was raised for Type Bs.


The arrival of Type B DLXs was around '26 as well. Please look at the idle bleeds to see if it has the later two holes, or the earlier Type A/GX bleed design:


BLEEDNO5.jpg

Please also look to see if the venturi appears to be brass, or potmetal, as that transition also crossed from Type As into Bs.

....Cotten
PS: Any Maldwyn Jones provenance would be priceless, of course!

(The most intriguing part of his AMA Hall of Fame biography is "Jones retired from racing at the end of 1922 to take a position with the Indianapolis-based Wheeler-Schebler Company, which was famous for its racing carburetors.")

[fouraceswes]

Wow! Super interesting stuff Cotton! I will get some more pics and information in a few days. This is a good one!

[fouraceswes]

Couple long weeks at work has kept me away from the mystery but here are some more pics. Let me know mir thoughts Me Cotton. I also found an obscure Google link to Maldwyn Jones’ patent for a carb. I will try and find and post that link.

[fouraceswes]

EDB63EC1-FB97-4057-8C23-EB85948B50AE.jpeg

[fouraceswes]

https://www.google.com/books/edition...sec=frontcover

[T. Cotten]

It looks like a potmetal venturi, Wes!

(They are horrible, but better than brass.)

Can't see the idle bleed, but the nickel is museum quality.

The patent search is greatly appreciated, as it appears to be the missing link between GX and DLX models, as the drawing incorporates both designs. I hope I can download it somehow, Thanks!...


....Cotten
PS: The Google format sux so bad I can't save the image yet, but I can see now it is the GX-4 and GX-9 design.
How curious that it is dated 1930, when the GX models were apparently production for 1926 to 1928.
(Late edit: I now can read the July 22, 1926 date).
Searching patent No. 1,736,700 doesn't work so far...

[rms337]

Cotten....this will get you there....it is the PDF.

https://patentimages.storage.googlea.../US1763709.pdf

[T. Cotten]

Many thanks, RMS!

You've got a significant historical artifact, Wes!

Is the slide shaped like the GX?

Is there any other provenance, or associated hardware that may hold clues?
(Whomever declared it a 'prototype' wasn't lyin'...)

....Cotten
PS: Note how the patent drawing shows an idle bleed 'jet', like my photo above, rather than the simple two holes .

[fouraceswes]

I will try and post a couple more pics but I can only seem to do it with my phone which always fouls up.

I got the carb out of a curio cabinet at the house of a friend who passed away a few years back. His family has entrusted me to research and sell some of his stuff. He was a collector and restorer of early American motorcycles and stuff related. It was surrounded by a "Senspray Carburetor" and several Herz and Herz Ruthardt magnetos s well as a Zenith Carb that had a tag on it saying "1924 Harley." The tag saying "one of one, prototype" and Maldwyn Jones" is the only clues I had to go on. Its possible he met Jones during his lifetime as Jones died in 1987 I believe and that was when my friend was restoring motorcycles of that era. But that was very very "pre-internet" and their paths would have had to have crossed some different way than just a google search.

[T. Cotten]

Merry Christmas, Everybody!

A web search suggests, Wes,
That I might have a Senspray on the ivy-covered Famous James in my front window. That's the first I've heard the name.

The prototype is undoubtedly just that.
After experience with prototypes in industry, academia, and Federal R&D (plus a little free-lancing with surgical instruments), the carb is most remarkable in that it is not a cobble. The tower on top of the body would have been an easy braze-up, yet we are led to believe it was a one-off pattern and casting, and plated, too.
How remarkable were the resources of a foundry/factory ninety-five years ago, that it didn't have to go into production!

In its simplicity, there is only one new variable to test, the variable venturi, which is why I wish to see its shape. How delightful it would be if it were different from the patent. But I am equally curious whether it has the bleed jet, or just holes...

....Cotten
PS: Thanks for sharing this, Wes; As far as telling the family its value, its priceless.