carbking

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  1. You might check "aftermarket flange adapters" under Technical. Jon.
  2. A question in another thread prompted this thread. EDIT: I have problems doing a comprehensive article on this forum, so have placed this one, with pictures and other data, on my website. Here is the link: http://www.thecarburetorshop.com/Aftermarket_adapters.htm In the 19 teens and twenties, many carburetor companies made aftermarket carburetors for many applications for which they had not sold the original carburetor. As many companies either ignored, or blatantly defied, S.A.E. standards, it was necessary to sell a flange adapter with the aftermarket carburetor. I have lists of adapters originally produced by Carter, Marvel, Rayfield, Schebler, Tillotson, and Zenith (and probably others). No, I will not publish these lists for a number of reasons; the primary reason being they would be mis-interpreted by many, and I would catch the flak! How? These adapters were made to adapt a SPECIFIC carburetor to a SPECIFIC application. So a Zenith adapter to adapt a Zenith size 2 type 105 carburetor to a specific application MAY NOT adapt a Zenith size 2 type 63AW carburetor to the same application. Why? Because the 63AW is physically wider than the 105. So looking at any of the lists for a cross-flange size 2 to size 3 adapter would get an enthusiast a part number for an adapter that would bolt to the carburetor and bolt to the intake, but maybe NOT allow the carburetor to fit in the allotted space between the engine block and the fender. So, the way we suggest to proceed. (1) Determine which carburetor to use to properly run the engine. (2) Determine which type of adapter will be necessary to adapt the carburetor to the engine: (A) straight (B) cross (C) rotated (D) offset Each of these will be discussed in detail below (3) Determine the dimensions of the carburetor with the adapter connected, and measure to see if it will fit. Types of carburetor flanges: (1) straight - a straight line drawn from center to center of the mounting studs would run from bumper to bumper on the vehicle (2) cross - a straight line drawn from center to center of the mounting studs would run from fender to fender on the vehicle (3) rotated - a straight line drawn from center to center of the mounting studs would not be parallel or perpendicular to a straight line from bumper to bumper. Good examples would be 1929~1931 Chevrolet 6 cylinder and virtually all single barrel Marvels produced after about 1925. The Chevrolet is rotated 30 degrees. The Marvel rotation varies. Types of adapters: (1) straight - the straight adapter will allow a carburetor with a straight flange to mount to an intake with a straight flange. Often this is quite easy. From a swap meet (or salvage yard if you are lucky enough to still have a salvage yard), acquire two unloved carburetors (we used Tillotson type JR, Holley 1904, and Rochester type B and BC) with cast iron flanges with the appropriate center to center spacing, place the throttle body in a power hacksaw such that the saw will cut the throttle body parallel to the flange just on the side of the throttle plate opposite the flange, acquire a short piece of steel pipe of the appropriate diameter, and weld it (or if you are me, take it to someone that CAN weld) all together. The completed adapter should resemble a capital letter "H" that fell over on its side. The cross-bar in the "H" is the pipe with an I.D. equal to the smaller of that of the carburetor or the intake. There must be sufficient distance between the legs of the "H" to allow nuts to be installed. (2) cross - the cross adapter will allow a carburetor with a straight flange to mount to an intake with a cross flange. Theoretically, the reverse is possible, but cross flange aftermarket carburetors are very rare. Because of the orientation of the nuts, often a cross adapter may be made as above but without the pipe; just weld the two flanges together. (3) rotated - the rotated adapter will adapt a straight flange carb to a rotated intake manifold. Often, like (2) above, it may be fabricated simply by welding two flanges together. (4) offset - the offset adapter, virtually always identified with Marvel applications may be necessary because using another adapter will cause interference with something (generator, steering box, etc.). The most common requirement for these is the 1926~1929 Buicks where one needs a rotated adapter WITH an offset. Basically, the offset is a small "S curve" in the pipe connected the two flanges. When fabricating the adapter, remember that for updraft carburetors, the vacuum of the engine is required to pull the fuel from the carburetor UP into the engine. Therefore the adapter should be as short as possible, given space and strength requirements. All of the above assume a two bolt flange. There were a few applications with 3, 4, 5, and 6 bolt flanges. The procedure is the same. S.A.E flange sizes (cheerfully ignored by Marvel, and some others): Size 1 - center to center 2 3/8 or 2 7/16 Size 2 - center to center 2 11/16 Size 3 - center to center 2 15/16 Size 4 - center to center 3 5/16 Size 5 - center to center 3 9/16 Jon.
  3. Ditto DualQuadDave's comments. If you are CONVINCED you have to go to a single quad: (A) There is no shiny brand new carburetor available THAT CAN BE MADE TO PERFORM, let alone as delivered out of the box, as well as rebuilding an ORIGINAL Carter single AFB for the Buick engine. The one you listed will require: primary jets, secondary jets, primary clusters, secondary clusters, different step-up rods, different vacuum piston springs and especially a different auxiliary air valve to come close to performing as well as an original. If you really want to use the carb you suggested, it will work well (as least for a little while) if you change out the drivetrain to a Chevy 454! (B) Electric chokes are best used on cars with manual transmissions (or for those enthusiasts that reside in Honolulu, San Diego, or Miami). VERY unreliable when used in colder climates on vehicles with older automatic transmissions. If you MUST, then tell your Dad to start the car, go back in the house and drink three to four cups of coffee to allow to engine to FULLY warm AND get him a subscription to triple A! Start it up, try to drive it, and it will stall at the stop light 3 blocks from the house, and it WILL NOT RESTART FOR ABOUT AN HOUR! Jon.
  4. carbking

    RTS 5215

    Fuel glass bowls should use either a cork (recommended) gasket or a rubber gasket (not as good as cork). Possible to crack the glass if using a paper gasket. You can acquire cork (probably 1/16 inch is sufficient) at the local parts house. Cut your own gasket. Borrow your wife's fingernail scissors to cut curves in the material. Jon.
  5. When the engine is cold, the choke should activate the fast idle circuit on the carburetor, causing a faster than normal idle. The higher RPM cold may be masking issues with rings or valves. If the hot and cold idle RPM's are quite different, I believe a compression test is in order. If the hot and cold idle RPM's are the same, I have no suggestions. Jon.
  6. In later years, when both vacuum and mechanical linkage was available, the return springs on the end carbs with mechanical linkage are MUCH lighter in tension than those for the vacuum linkage. The springs for the vacuum linkage are STIFF, and should be. If correctly functioning, the vacuum motor will jerk the end carbs open when the vacuum is applied from the vacuum canister. Jon.
  7. I don't believe the Demons will fit the manifold; however, If I am wrong about that, the air cleaner will not fit, the fuel lines will need fabrication, the linkage will have to be fabricated, and you will probably need to fabricate a kickdown as well. The calibrations will be completely wrong, so complete recalibration of the Demons will be necessary. And (opinion) even if you are a Demon guru, I doubt very seriously if you can make the Demons runs as well as the original Carters. Plus, (also opinion) if you ever sell the car, you can deduct the cost of acquiring the correct Carters from your selling price, and the universe of potential buyers will probably be halved. Jon.
  8. Original thread size 1/2 x 32. Jon.
  9. Alan - this link will explain the bore or "throat" size, and also the internal venturi sizes: http://www.thecarburetorshop.com/Stromberg_SF_carburetors.htm Note that some SF-4's do have accelerator pumps, others do not. The numbers from your tag don't seem to show up in the Stromberg literature. The best way to get a feeling for if a specific carburetor has or doesn't have an accelerator pump, is to look for the presence of the pump adjustment screw. Go back to the link, and scroll down to the pictured SF-4 carburetor. In the upper left corner of the picture is a long vertical 10x24 fillister headed screw. This screw is the pump adjustment screw. By varying the depth (adjustment) on this screw, one can vary the length of the pump stroke, thus saving gasoline????? The carbs without an accelerator pump will not have the screw, rather just a short headless brass plug in the machined hole. And the variable aspect, using your words, is in the internal venturi size. The physical size (SF-4) is the external size. The venturi size determines airflow. And the jetting is selected to correspond to the airflow. Jon.
  10. Some of the early WCFB carbs had some weird secondary lockout linkage, that if not adjusted absolutely perfectly, can cause your issue. This included the linkage from the choke to the lockout. Do not remember if the Buick carbs used it, but Cadillac did. I have spent hours adjusting on some of the Caddy WCFB's to get them to function correctly. Worth a look. Jon.
  11. Al - the SF-3 has 1 5/8 bore; while the SF-4 has a bore of 1 15/16. Jon.
  12. Matt - you might check this link: http://www.thecarburetorshop.com/Automaticchokes.htm Jon.
  13. Congratulations. You have found an un-recycled Rayfield model HC. Produced by the Marvel/Schebler division of Borg-Warner. Sold with a water decal stuck on the end of the bowl with the "name du jour" (Wizard, Rayfield, Johnson, M/S, etc.). It could have been purchased through Western Auto, J.C. Whitney, Warshawski, etc. Jon.
  14. 1 psi I can easily believe; really had an issue believing 3. I think you have now found your problem. I brought up the oscilloscope because of the 3 psi. I inferred from your post that the carb would stand 3. Wasn't convinced, but also didn't wish to argue. So the next logical place was voltage. I am a firm believer in testing. There are some incredibly knowledgeable helpful folks here that will try to help; but all of us are trying to "diagnose an upset stomach by telephone!". The more testing information which is provided helps reduce the number of possibilities. Happy that you found the regulator issue. Enjoy that Buick! Jon.
  15. There are several items to consider concerning the amount of fuel pressure the carburetor will handle: (1) Orifice of the fuel valve seat (2) Effective pressure exerted by the float (2A) Buoyancy of the float (material, and fuel volume displaced) (2B) Mechanical advantage of the float (position of float arm, and type of float fulcrum). While we have brass floats available for the early Marvels, the brass float does virtually nothing for buoyance (maybe a few percent). The brass float does have much better reliability than the original cork or the modern polynitraphyll (sp) closed cellular foam. Since the fulcrum position and style are unchanged, the float will exert only marginally more pressure. Even if you are using the brass float, and have significantly reduced the fuel orifice; being from Missouri, I would have to be shown that this carburetor is capable of 3 psi, because of the fulcrum design and placement. However, not certain this is all of your problem. As mentioned by others in this thread, ignition systems are less reliable than carburetors (even Marvel carburetors ) Generally, a carburetor has very little personality. It will behave the same under similar conditions. The fact that the engine will idle, sometimes run, and then act weird to me indicates ignition issues. If the ignition is insufficient to fire the available fuel, then the plugs will be sooty just as if the carburetor was malfunctioning. Unsure what tools you may have available to you. Readings from a clamp-on volt-meter on the plug wires when the engine is behaving, compared to when it is misbehaving would be interesting. But just because some of us feel your coil may be suspect is not a REASON to change it! Ignition systems CAN be tested. Find a local friend or shop with an older Sun or Allen diagnostic oscilloscope (and knows how to use it) to hook up to the engine. Jon
  16. Generally, this condition is caused by the pump discharge valve being stuck. If the valve is closed, the gas has to go somewhere, and it bypasses the pump skirt, shooting up alongside the pump. A clogged discharge passage would cause the same condition. Jon.
  17. Will the car restart immediately after shutting it off? 3-month old (or older) fuel could be the culprit, however: http://www.thecarburetorshop.com/Troubleshooting.htm#Acceleratorpumps http://www.thecarburetorshop.com/Troubleshooting.htm#Hardstartcold VERY IMPORTANT to have started the engine prior to doing the accelerator pump test. For the record, if I had a dollar for every "faulty" accelerator pump that has been unnecessarily replaced in the last 20 years alone, I could probably pay off the National Debt and be a hero. As far as the use of starting fluid is concerned: I don't KNOW, but personally I like it and have used it on everything from weedeaters to large tractors for almost 60 years with ZERO issues. NOT a recommendation to others, simply a statement of personal use. Incidentally, one of the vehicles on which I used it was traded after 440,000 miles (body had rusted for the third time due to Missouri salt and cinders - thanks MoDot) and the cylinder head had never been removed from the engine, which still ran well. Jon.
  18. Interesting thread. I have no answer, but will pose some thoughts. I learned long ago when a vehicle is restored to "original", all of the original issues are put back into the vehicle. Example: the four way fuel fitting on 1964~1966 Pontiac GTO's ALL broke! The reproductions made by the same company with the same specifications.........will break! I collect Pontiac literature. By the 1930's, Pontiac put out dozens to hundreds of bulletins annually of factory "patches" to make the car better. How does one view modifications done at the suggestion of the manufacturer by employees of the manufacturer. And to relate the above to my area of expertise - Packard by August of 1929 "suggested" the removal of the Johnson carburetors (first fitted in April) and replacement by Detroit Lubricators. So does a change to a more reliable carburetor that also produces more horsepower at the manufacturers' suggestion make the vehicle a hot rod? Jon.
  19. Just a suggestion: before doing anything else, get the identification number from the top of the carburetor (stamped into the metal, NOT a raised number) so we can determine how much of a mis-match the BXV is for the fluid drive. I tend to believe the compression is significantly low, but the wrong carb might be contributing to the overall problem. The BXV, BXVD, and BXVES are types or styles of carburetor. They come in all different sizes and calibrations. Simply stating you have a BXV is about as informative as me calling my doctor and telling him my feet hurt! More information can suggest if the carburetor is part of the problem, or not. If the carb is an O.E. application, then looking straight down on a CLEAN top casting in the area approximately above where the fuel inlet enters the bowl should yield the identification number. If Dodge, it will be in the format 3-nn, or 3-nnl, or 3-nnn or 3-nnnl. The 3 represents Dodge. The small nn or nnn represent an unknown 2 or three digit number. The small l represents a letter (A,B,C, etc.) that states the engineering status of the carburetor. No major revisions, no letter. One major revision, letter A. Two major revisions, letter B, etc. Example 3-97 (3=Dodge, 97=identification number). Second example 3-95B (3=Dodge, 95=identification number, B means 2 major revisions). Jon.
  20. To a degree, thanks. I have the Dykes information. There is also some general information in the Radco manuals. But what I would really like to find is "factory" information, rather than aftermarket. Really would be nice to find some factory Oldsmobile, Locomobile, Peerless, etc. factory parts books with individual parts listings. I do have some of this for Studebaker. Jon.
  21. Remember the cartoon of the ancient Egyptian sitting on the Caterpillar after he had just finished the pyramid. His comment "we'll disassemble the equipment, and 2000 years from now, no one will be able to figure out how we made these". Stromberg borrowed a page from the above. The wires are an idle channel restriction, to increase velocity of the idle mixture. They are mentioned in the Stromberg literature, but I have found no mention elsewhere. Jon.
  22. Depends on what you need. I know we are out of vane boxes, and the company that cast them for us many years ago changed hands, and threw away our molds! Let me know your "laundry list" and will see what we have. One of the reasons I recommended Classic Carbs in Phoenix is that they have a machine shop along with the carb rebuilding. They are quite capable of machining what they require. And 6 months for quality carb rebuilding is really pretty quick. I need to recommend them more often! When our backlog hit 3 1/2 years, we simply said "no more"! Jon.
  23. Alex - please take no offense at this post, as I am not posting for that intent, merely to offer advice. First, remember that I no longer rebuild, only supply parts, so NOT grinding my own ax! The Detroit Lubricator (opinion) is one of the finest of the updraft carburetors. It is also one of the most misunderstood, and has a steep learning curve. Why? The Detroit model such as yours was used only on Cadillacs, Grahams, and Packards. So the average mechanic did not see as many as Carters, Strombergs, Zeniths, etc. Also, Detroit Lubricator did NOT have a retail division such as Carter, Stromberg, and Zenith. Why is this important? Because there are NO factory books, brochures, instructions, etc. other than in the literature of Cadillac, Graham and Packard. 40 years ago, I started to do a book on the Detroits. I acquired the Graham and Packard literature (never found the Cadillac), and then "life" happened, and the book got unwritten. The Detroit Lubricator was an early form of variable venturi carburetor, and it has MANY "gotchas" which are not found in any of the literature; one only finds them through experience. Once properly rebuilt, they are quite reliable. For the above reasons, I would suggest you consider having these carbs professionally rebuilt (remember, I don't do this any longer, just supply parts). I understand budget constraints; Dad always accused me of "having champagne tastes and beer income". I wanted an XK-E, and settled for a TR-3 (still would like to have an XK-E but it won't happen in this lifetime). I am reminded of a gentleman a long time ago that sent me a Carter BB-1 (Chrysler 1932) for restoration. I called and quoted him $500. for the job. He said "that's too much, send it home" which I did. About 2 months later, I received it back, mostly apart, and butchered; with a note, please rebuild. I called him again with a $1200. estimate. He asked why. I bluntly informed him that he had done $700. worth of damage. This time, he OK'ed the rebuild. Just food for thought! One carburetor restoration company of which I am aware that does excellent work is Classic Carburetors in Phoenix. Jon.
  24. A huge thank you for whatever you did to the search engine. The exact same search that I try to do daily (on either of 2 different computers) that has been taking from 2 to 5 minutes since the new format is now taking 2 to 5 seconds!!! I have made no changes, so it has to be you. Thanks again, and a larger thumbs-up! Jon.
  25. Alex - we did several of the conversions 25~30 years ago, but replacing the Johnson carbs on the earlier 12 because of reliability, not the Detroits. I don't remember ever doing the conversion replacing the original Detroit carbs. Ed mentioned that very few individuals swap out carbs and have them tuned correctly. I would more or less agree, for two reasons: (1) the wrong carb is selected, often because of price, and (2) the seller and owner are unaware of what must be done to the carbs to make them work. But, there are even fewer individuals that can make a Johnson perform well, and maybe nobody that can make one reliable. Hence, our developing the swap. A few things to consider: (1) the Zenith we used was O-10870 (we bought the ENTIRE existing inventory from Zenith, and we are now out!). (2) THERE IS NO CURRENT PRODUCTION BENDIX-ZENITH THAT MAY BE USED FOR THE SWAP! (3) The O-10870 was NOT a plug-and-play bolt-on swap, it required internal and external modification. (4) And even modified, it required adjustment when installed. Did they work? Yes, exceptionally well (but so do the original Detroit carbs). I have not seen David's reproduction of the Detroit. I do know I have spoken with him several times years ago, and sent him a lot of Detroit parts and information (we have rebuilt hundreds of Detroits over the years, so had a wee bit of experience with them). No, I no longer rebuild, too busy with the manufacture of parts, so please don't call asking me to rebuild yours. And just for the record, on my scale of 1 awful to 10 wonderful: Zenith 10870 - 9.5 Detroit - 9.5 Johnson - minus 3.0 If you have an original set of Detroits, there are still a few in the business that CAN refurbish them correctly, if you have patience. Anyone that is any good has a backlog! I would suggest giving Ed or David a call, or I will be happy to speak with you as well. My number 573-392-7378 (9-4 Mon-Tues ONLY central time). Jon.