Carburetor rebuilder help

[ricosan]

I have an early '30s carburetor that I would like to have rebuilt. I'm not asking anyone for recommendations but I would like to hear from anyone who had a good a good experience with a particular shop. I've read a few good things about "Karb King" but their website looks to cater more to post war carburetors. I could be wrong.

Any help would be appreciated.

ricosan

[edinmass]

Please list the car it fits as well as the brand name on the carb. A model number would also help. There should be no problem rebuilding the carb, as far as the fuel pump , gas tank, and other issues the car may have; they should also be looked at.

[ricosan]

Hey Ed,

It's from a 1932 Marmon. It's a Schebler Model - S, 1 1/2 Duplex. It would be fantastic if someone had experience with a schebler rebuild, good or bad I would love to hear.

I'm also interested too in people's experiences with any pre-war antique carburetor rebuild/restoration no matter the make.

All of the rebuilder I've looked at make bold promises. How do I tell the good guys from the bad guys?

ricosan

[carbking]

Interesting.

There is no record in Schebler literature of Schebler selling a 1 1/2 in duplex to Marmon.

The 1 1/2 inch Schebler duplex carbs were sold to Duesenberg, Lycoming, Scripps, and Stutz.

If you would supply the identification number, it would aid in determining the original application.

Rebuilding kits are available (but again, the number is mandatory).

Once the Schebler is cleaned, or kitted, or rebuilt, or restored or whatever is the current buzzword, by a novice, an apprentice, a master mechanic, or a carburetor engineer; it will leak if fuel is placed in the fuel tank.

If I were going to have one restored (since I no longer have time to work on carbs due to the demand for rebuilding kits); I would contact Classic Carburetors in the Phoenix area to do the carburetor AND companies providing automatic underhood halide fire estinguishing systems. Please note that the halide would be installed for any Schebler installation, regardless of who works on the carb.

And, UNLESS this is a one-off racecar, or some other experimental, or there is some legitimate reason for the Schebler being present on the Marmon; I would highly suggest trying to determine the correct carb (probably a Stromberg UUR-2) and acquire one (and this is advice only, we are sold out of the UUR-2 carbs!).

Jon.

[edinmass]

Jon, (carbking) gives good advice. The Schebler will fail. The shop I work with has a UUR-2 on ebay right now. It's the last one left, he doesn't have any more good cores. They aren't cheap, but the car won't burn. PM me if you want his contact info. Like your car, I have been after a similar one for more than 30 years, so far no luck.

[ricosan]

Hey Guys,

I've looked for the number on the 3 sides that I can see but I see no numbers. I wrong about the information stamped into the casting. It says "1 1/4 Duplex" It may be on the back side. I will get a mirror and see If I see anything.

I believe that this was the original carburetor for the car. This car has the "Big Eight"/125HP engine. Here is a photo from the carburetor section of my "Marmon Big Eight Information Book" published by the Marmon Motor Car Company.

[hursst]

Please see my PM...

[carbking]

Marmon used three different Schebler model S duplex carburetors:

(A) domestic 1930

( export 1930

© domestic 1931

The identification number for the duplex model only is stamped on the TOP (the single barrel carbs have it on the end). Midway between the air valve assembly and the throttle there is a "hump" that covers the intermediate shaft for the air valve lockout. The number on the duplex models will be stamped about this hump. The identification number will aid in what carb you have.

My previous post about a leaky duplex 1 1/2 inch carburetor still applies to the duplex 1 1/4 inch carburetor.

Marmon used the Stromberg as well as the Schebler in 1931, and the Stromberg in 1932.

Jon.

[ojh]

Marmon used three different Schebler model S duplex carburetors:

(A) domestic 1930

( export 1930

© domestic 1931

The identification number for the duplex model only is stamped on the TOP (the single barrel carbs have it on the end). Midway between the air valve assembly and the throttle there is a "hump" that covers the intermediate shaft for the air valve lockout. The number on the duplex models will be stamped about this hump. The identification number will aid in what carb you have.

My previous post about a leaky duplex 1 1/2 inch carburetor still applies to the duplex 1 1/4 inch carburetor.

Marmon used the Stromberg as well as the Schebler in 1931, and the Stromberg in 1932.

Jon.

Hey Jon, can you eloborate on the 'leaky' part? What needs to be done to solve this? You peaked my interst and I Pm'd 'ricosan' and offered to go thru it for him if he didn't find an expert to do it. This is a systemic problem?

Thanks, oj

[carbking]

OJ - the simpliest way to prevent a Schebler from leaking is to not put fuel in the fuel tank.

When the tank is emptied, the Schebler will stop leaking!

If you want a more detailed explanation of why it leaks, and why you won't stop it from leaking; give me a call at 573-392-7378 (9-4 Mon-Tues central time).

If a professional does the carb, he/she can GENERALLY prevent it from leaking while running. When the engine is turned off it WILL leak. Using a fuel shutoff to turn off the fuel first, and then allow the engine to die when the fuel level in the carburetor is too low to function normally will minimize, but not stop the leak.

Jon.

[GLong]

Wow, that sounds like a serious design fault in that carb. Does anyone have a cut-away drawing of the carb to show what is wrong with the design ?

The UUR-2 is a good carb, but it has it's share of issues due to the potmetal carb body.

I'd love to dissect one of these type S carbs and figure out it's faults.

Greg L

[Guest Commodore]

Gunbroker.com has a Schebler Model S Carburetor Brochure and Parts List for sale for $20. If you are going to deal with Schebler Model S Carburetors this would be good thing to buy.

http://www.gunbroker.com/Auction/ViewItem.aspx?Item=393940369

Here is a parts breakdown from that brochure.

[ricosan]

Thanks for all the information Guys.

Jon - I haven't noticed any gas leak problem but I will pay closer attention. No unusual gas smells. Could it be that this problem in design was remedied sometime over the past 80 years? My carburetor is mounted just like the attachment that I posted. I can't get a good view of the back side without taking it off. I used a mirror and I can see something on the backside but it looks like a word stamped there. Is the number located on the back side?

Commodor - Thanks for the heads up. I'll be bidding.

ricosan

[GLong]

And when you win that parts breakdown, may I please have a copy? I want to see the design faults.

Thanks

Greg L

[carbking]

OK, I didn't really want to type this much, but:

First, there are 460 different Schebler model S carburetors, which carry identification numbers from SX-1 to SX-460.

There are several different styles of the model S carburetors, and in fact there are SIX DIFFERENT pages similar to the one posted above, with associated material in the Schebler master parts book (depending on the printing, there were several, about 1 1/4 inches thick).

Now, as to the leaks:

Look at the illustration posted. Notice that the primary air for the Schebler comes in the very BOTTOM of the carburetor. When the engine is turned off, all of the fuel in suspension in the intake manifold and the carburetor plenum above the throttle plate, which was being held by engine vacuum drops (gravity). Where does it drop? Out the bottom of the carburetor. In fact many car manufacturers actually put a "drip plate" and a drain tube underneath the Schebler to carry away the leaked fuel.

Additionally, take another look at the illustration. Do you see the bowl to body gasket? If you do, you have an excellent imagination, because Schebler didn't see the need for one, and thus didn't use one on most model S carbs. Park on a hillside and watch it leak.

The two keys to making the Schebler work as well as it possibly can (of course, ignoring the leaks) is the air valve spring (new ones are available in the repair kits) and the clearance of the needle valve seat (this is the long vertical seat that rotates around the metering needle, not the fuel valve seat) to the main body.

Jon.

Edited February 17, 2014 by carbking (see edit history)

[GLong]

So it's much like my Rayfield carb on my '15 Chandler, it has a fixed 'idle air' passageway, a bottom main air intake, and the air moving past the vertical piston that mechanically adjusts the mixture.

I understand why you say it will leak.

Greg L

[ojh]

OK, I didn't really want to type this much, but:

First, there are 460 different Schebler model S carburetors, which carry identification numbers from SX-1 to SX-460.

There are several different styles of the model S carburetors, and in fact there are SIX DIFFERENT pages similar to the one posted above, with associated material in the Schebler master parts book (depending on the printing, there were several, about 1 1/4 inches thick).

Now, as to the leaks:

Look at the illustration posted. Notice that the primary air for the Schebler comes in the very BOTTOM of the carburetor. When the engine is turned off, all of the fuel in suspension in the intake manifold and the carburetor plenum above the throttle plate, which was being held by engine vacuum drops (gravity). Where does it drop? Out the bottom of the carburetor. In fact many car manufacturers actually put a "drip plate" and a drain tube underneath the Schebler to carry away the leaked fuel.

Additionally, take another look at the illustration. Do you see the bowl to body gasket? If you do, you have an excellent imagination, because Schebler didn't see the need for one, and thus didn't use one on most model S carbs. Park on a hillside and watch it leak.

The two keys to making the Schebler work as well as it possibly can (of course, ignoring the leaks) is the air valve spring (new ones are available in the repair kits) and the clearance of the needle valve seat (this is the long vertical seat that rotates around the metering needle, not the fuel valve seat) to the main body.

Jon.

Thanks Jon, just like everything else in this hobby: its always more complicated than it should be.