carbking

The first 3921s carbs came with the 170-839s choke housing assembly. Sometime during production, 170-839s was discontinued, and superseded by 170-911s. Either will fit and work on the 3921s carburetor. The Master Parts Index does not specify the exact date of change (this would be on the original drawing, and no offense meant, only necessary for an exact numbers-matching car, so not going to look it up); nor the reason for the change (this information may or may not be available on the original drawing). Jon

1963 Jon

I also am surprised by these figures. Perhaps a torque wrench reading in pounds-feet is less accurate at lower values. Perhaps a torque wrench reading in pounds-inch and then converting to pounds-feet might yield differing results. Jon.

The choke housings are different. 3503s - 170-785s 3921s - 170-839s (superseded by 170-911s) Sorry. Jon

(1) Mill the remaining projection from the outside of the choke cover (2) Machine a custom brass fitting on your lathe. The fitting should have the correct male thread on one end, and a small shoulder to fit against the outside of the choke cover. On the inside of the shoulder, the fitting is tapped to thread into the choke cover. The fitting should have approximately the same inner diameter as the original. The very inside end should be milled on either side to have a slot that will hold the spring. The threads that thread into choke cover should be approximately 1/8 inch too long (standing proud of the cover on the inside by 1/8 inch). (3) Tap the choke cover for the same thread as you used on the fitting (4) Machine a brass nut 1/8 inch thick with the same thread. (5) Assemble the fitting into the cover, and secure with the nut. (6) Re-install the spring (7) Re-install the cover on the carburetor. The inner clocking will be off; although this can be corrected by only threading the last 1/8 inch going through the cover, rotating the fitting until the correct clocking is obtained, and then secure with the nut. I prefer to have the cover threaded. Some items are made of unobtainium or verypricium and must be fabricated. If you found two on ebay, then this item made not be one that deserves this amount of fabrication. Jon.

Also, make certain, the spring is activated by heat the same way. Have not tested all of the Rochester chokes, but Carter made some that were wound the same way; but uncoiled in opposite directions when heat was applied. Jon.

No, they won't all fit, but most of the ones with the male fitting on the outside of the choke will fit, and can generally be adjusted to work. Jon.

Just for the record, my older vehicles like the cold a LOT better than the new electronic marvels like it. The newer cars with all the live sensors drain the battery in this cold in a couple of days if not started. Jon.

West - check the "rich - lean" direction arrows to start with; then check that the inside "slot" is "clocked" the same as yours. Of course, you can always ignore the original setting by number of bars, and just set the choke, but if trying to keep original, then clocking is important. There are other differences in the lettering that probably is no longer important, but I have had some very "intense" customers over the years. The springs also have a different coil length to control the timing, but again, one can generally adjust for this. Automatic chokes were one of the "cash cows" for the carburetor companies. Change the clocking 2 or 3 degrees, change the part number each year; and EVERY dealer would order 2 of each at the beginning of the model year! Jon.

I have very little experience with Webers, so one can decide if the following has any applicability to the Webers: When we were still restoring zinc alloy carburetors made in the USA in the 1930's, it was not uncommon for a fiber washer gasket surface to requiring "facing" due to deterioration of the zinc alloy base metal; in order for the fiber washers to seal. I have not seen this issue on post WWII US-produced carburetors by the major brands. European carburetor makes other than Weber (ie Solex and British Zenith) used a zinc alloy in the 1950's and 1960's that was much WORSE than that used in the USA in the 1930's! Again, I have very little experience with Webers. Jon.

It would not seem to be the case, but there are MANY DIFFERENT of these things. New old stock is best, and probably quite expensive if you find the correct one. Good used is second best, and somewhat less expensive, if you can find the correct one. Repairing what you have would be the next choice. The brand new powder cast versions have no rigidity, and will not hold up, other than as paperweights. Both of the ones you picture are fixable. Jon.

How much torque is too much torque depends on the diameter and pitch of the threads, plus the material with the female thread. For Webers, I don't know; but would suggest you contact the factory. I am going to offer a different opinion to some of those already expressed in this thread: (1) For fuel use, fiber washers are superior to nylon washers (they crack). (2) Unless told to do so by the manufacturer, NEVER use a sealant around fuel (or learn how to rebuild the carburetor(s) ) Personal and professional opinion - anytime the carbs are removed, the sealing washers should be replaced with new. Figure out the diameters and the thickness, and order a box of them from McMaster-Carr. Jon.

What you show is what was/is used. Yes, it can be problematic. A little corrosion on the zinc threads, an impatient "mechanic" and the fitting is cross-threaded. Have seen many choke housings that were damaged. Different "fixes" can be tried: rethreading the end with a die, cutting off the end if too much metal has been removed, then rethreading, there even used to be a brass fitting that could be screwed into the zinc (self-tapping threads) with new threads for the regular fitting. This fitting repair was the darling of some of the least expensive commercial carburetor rebuilders, and was generally good for one time use, then totally ruining the choke housing beyond repair. Yours looks like there is sufficient metal left to cut off the end, and touch up the threads. Jon

Mark - give me a call during normal telephone hours. Jon.

You guys just had to bring up the cow magnets!!! I am indirectly partially responsible for the great cow magnet fiasco! My apologies.A lot of years ago, got a call from a gentleman in Texas that had rust issues in his fuel and was going to take the car to the Pate show in a couple of days for sale, and could I overnight a rebuilt carburetor to him today?Well, the answer was no, but: I told him about the Carter Magna-trap. This was a magnet with a special shape to fit into a Carter glass bowl fuel filter. I have told many enthusiasts about this, and suggested one of the refrigerator magnets like your better half uses to stick honey-do jobs to the refrigerator.He told me he had a dairy farm, and had several of the cow magnets (cows are stupid, they will eat just about anything, including baling wire....oops, showing my age again ). If you feed one of the magnets to a cow, the wire doesn't pass into the entire digestive tract (you city folks, use Google, not about to get into the digestive system of a bovine ) He would make a loop in the fuel line and tape three of the magnets to the loop, hopefully to stop the rust from passing into the carburetor.About 3 days later he called, and he was laughing so hard, it took about 15 minutes for him to repeat the story. Seems everyone that looked at the engine asked about the cow magnets. After the first few, he started with a story that he continued to embellish as the day wore on. The final story was the magnets created a flux field, supercharging the fuel molecules, and giving almost non-Newtonian power and fuel economy!Well, you guessed it. P.T. Barnum scores again! This even made the Johnny Carson show (remember the "headlines" segment)? Over 300,000 cow magnets were sold in the southwestern United States within a month. Every supplier was sold out, and had back orders.Here is a link to a picture of the Carter Magnatrap that I placed on my website:http://www.thecarburetorshop.com/Carter_Magnatrap.jpgAnd now you know "the rest of the story" Newspaper story: https://www.washingtonpost.com/arch...noredirect=on&utm_term=.19601413ca5dJon.

I do not know what may have been printed for service in some of the O.E. shop manuals such as Waukesha, Hercules, or American LaFrance; but Stromberg did not print such a manual. Stromberg printed 2 pages in their service manual which contain: one cut-a-way drawing (not exploded), adjustments, parts numbers, and a picture of all the parts. Stromberg placed the parts on a white sheet in an order in which they took up the least amount of space, and took the picture. No physical proximity of parts intended. As far as the brass screw headed or hex headed plugs are concerned: Remove the zinc alloy parts (the venturi), the float, and all springs. These are parts that would be ruined by heat. Now heat the casting in an ELECTRIC toaster oven just as hot as you can get it. Remove the casting from the oven, and heat the cast iron AROUND the plug with an acetylene torch (propane isn't sufficiently hot) until starting to show red. Do this for all of the plugs. Return the casting to the toaster oven, and heat as hot as you can get it. Turn off the oven, and allow the casting to completely cool. DO NOT QUENCH. Remove the casting from the oven, and remove the plugs. Jon.

First, I am sorry you are hearing challenged. In the past, we got lit up, not once, but twice, on the internet from potential customers who got a price on a carburetor in an email; then acquired a money order which was mailed to us without calling to confirm the order. Of course, both times the carburetors has been sold to a customer that called. Since then, company policy has been to price kits (which we make, therefore will not run out) in the emails; but NOT to price carburetors for which we have no source if we run out). Again, sorry you are hearing challenged, but this policy will NOT change. When someone calls for a carburetor, we give a price that is good for the duration of the telephone call (I have a list of prices, and the price doesn't change, but the availability might change). And in your case, the carb was sold this morning. Thought maybe it was a friend of yours, but guess not. So now, out of the 7-69. EDIT: Rand Broadstreet (a couple of posts above) states he has some, and his email. Jon.

They were NOT good carbs, even when new. Chrysler design, built by Carter. They were so bad, Carter thought it necessary to publish a troubleshooting guide to attempt to help customers, and minimize complaints: Chrysler Ball & Ball carb troubleshooting guide Of all the carbs Carter ever produced, this was the only one they thought needed a troubleshooting guide. (Opinion) the first decent Ball & Ball downdraft was built in 1939. Carter felt the same way, as in 1939, Carter released service replacement carbs for the 1933~1938 carbs. Jon.

I have no dog in this dogfight However, I have always appreciated the irony of Schebler Carburetor Company promoting their carburetors for firetrucks. This meant a firetruck was present to put out the inevitable engine fire from a leaky Schebler carburetor!!! Evidently, the CEO's of a number of truck companies did NOT appreciate the irony; as in 1932 (the Stromberg SF/SFM series carbs and the Zenith 63/263 series carbs were introduced in 1931) a number of truck companies REQUESTED service replacement carburetors (to replace the Scheblers) from both Stromberg and Zenith. Many of these were issued O.E. part numbers, and one may assume these were sold through the truck dealerships. Jon.

The O6H with three hole base (list number 126) was used 1941 and earlier. The O6H with four hole base (list number 202) was used 1942~1948 https://www.thecarburetorshop.com/Klincoln.htm You can see they use two different repair kits. Jon

Ed - I started using the analogy some 40 or so years ago, after a Stromberg came into the shop with every single brass hex nut now round with clinch marks from pliers. Not as bad as the folks using needle-nose pliers to remove Stromberg jets because they are too frugal to buy (or fabricate) a Stromberg jet wrench. We had to make several plugs with oversize threads because the needle-nose pliers rubbed out the body threads. Don't know if I coined the phrase (I did for me, anyway), but if so, you have my permission to use it, without royalties! Jon

They are two different type E carbs. As to exact identification, the ONLY reliable method of which I know to identify these early Marvels: (1) Start with the ILLUSTRATED Marvel parts book. (2) Using the pictures, identify the part numbers for: insert assembly, throttle arm, throttle link, and choke arm. Now go to the Marvel Master Parts listings, and go through the listings one by one until you eliminate all but one with all of the part numbers. Don't be surprised if "Dr. Goodpliers" (the evil twin of Mr. Goodwrench) has "married" two or more carbs together 75 years ago. Unless you have time to watch paint dry, probably economically unfeasible to try to exactly identify these units. We don't even try unless we have a sale for one. Then often easier to just assemble one from the parts listings rather than trying to find one. Jon.

When the carburetor is off, the mounting gasket should be compared to both the bottom of the carburetor flange assembly AND the top of the intake manifold. Migrating carburetors to a different application will sometimes get one in trouble with the mounting gasket for the carburetor being incorrect for the intake manifold. Jon.

Walt - two different stamps of the 1908 Locomobile "Old 16" were issued 30 December 1986 by Tuvalu Nanumea. Scott catalog number 28a, and 28b. Michel catalog numbers 103 and 104. These were issued as a part of the "Leaders of the World" issue over a number of years, and countries. While these stamps were legal for postage, they were issued with the collector market in mind. Jon.

If one is looking for pictures: Ebay Use search string: postage stamp cars Should find 10,000 or more Jon.