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Everything posted by carbking

  1. John - I don't think it is the use of two primary carbs that is the issue. I have been building and selling multiple carburetion for 40 years, and except for those building numbers matching showcars, ALWAYS use chokes on ALL of the carbs and solid linkage. Not just Buick, but all makes. My 1968 Ford F100 with a 435 HP 390 has two 625 CFM Carter AFB's running solid linkage, and manual chokes on both. Have done several Buicks over the years, and ALWAYS used two single carbs, as they were less expensive for the customer than fronts. They work well. Jon
  2. John - if I misunderstood, my apologies. I may have misread the comments. Flooding an engine when cold, to me, means either (probably) defective spark, or the carburetor is adjusted to rich. If the carb is the issue, then holding one's foot to the floor will activate the unloader circuit, but the choke will only be approximately 1/4 inch open, and the engine would flood worse. Just to prove this to myself, I would start the car, get it to normal temperature, and check the A/F ratios, especially at idle, adjusting if necessary. If the same thing happened again, I would check the firing voltages at the plugs. Jon.
  3. The PA did not use the BB-1 as original. The PB did. Do not know if the intake is the same or not. Jon.
  4. Carb looks like Plymouth. Picture is not large enough to tell for sure. There are letters on the carb that would give us a better idea, but cannot read them from the picture. Jon.
  5. Mark - it isn't JUST Marvel and Schebler, although I believe them to be the worst offenders; but Dodge (Detroit Lubricator) used a 27/64 by 22 thread up through 1929 for the fuel valve seat, and Ford Model A (1928~1931) (Zenith and Holley) used a number 10 by 34 thread on jets. This is just the common makes. Just got an order for a kit for a 1920 GMC with a Marvel and a 31/64 fuel valve seat thread. Another custom die ☹️ I understand how you can rob Peter to pay Paul on your own vehicles, but don't think I would last very long in business selling used fuel valves in my rebuilding kits Jon.
  6. Back out the air screw. Try 1/2 turn, maybe as much as 1 full turn. It is an inverse idle circuit. Lightly seated is maximum RICH. Your description sounds like an overrich idle. Jon.
  7. I will disagree on holding the petal to the metal on a flooded engine with today's fuel. Hot starting Jon.
  8. When the country in question was Japan some 50 years ago, a close friend, now departed, used to say "They are not out-smarting us, we are out-dumbing them!" Lots of possibilities in this discussion, but the mentioned Global Shipping Policy of ebay is....................well, unmentionable among gentlemen! Of course, the answer to getting the tariff on Chinese made products, is to, when possible, buy non-Chinese made products. We have been in the retail (and wholesale) market for old cars for 50 years, and have not sold one single item produced in China. It costs more, but if one is adamant, it can be done! Jon.
  9. Matt -thanks for the plug Which brings up a question. I have very little experience on pre-war cars other than their carburetors. Just took an order for another obscure Marvel kit (all Marvels are obscure the first time ) The thread on the fuel inlet valve seat is a perfect 31/64 by 20. Being weird is pretty normal for Marvel carburetors; Marvel did not adhere to S.A.E. standards, period. I guess this was one way of preventing anyone else from making aftermarket parts. So I get to have another custom die made. I currently have more than $10,000 invested in taps and dies, virtually all of which are 1/2 inch or less!!!!!! Marvel was the worst, but Schebler came in a close second. Zenith and Detroit also used a few unusual threads, but only a couple of sizes. So my question, just for my own information, do those of you that regularly work on these early cars, have issues with odd ball thread sizes; or is this just a Marvel and Schebler thingy? Jon
  10. Carbking read the thread, but did not answer, as the thread asked for experts, and carbking is a specialist, not an expert. Experts write sports columns, and when their prediction does not come to pass, the game result is labeled an "upset"! But since my bell has been rung (twice), my opinion is the BB1D is WAAAAAAAAAAAAAAAAAAAY too small! Carter released three sizes of the BB1 updraft carburetor. The BB1D is the middle size. The largest engine Carter suggesting using the largest BB1 on is 315 CID. The BB1D works really well on older engines around 215~250 CID. On newer engines, with more RPM, about 225 would be the upper limit. Jon.
  11. No gasket necessary, and Marvel did not use one. Jon.
  12. As long as the idle mixture control screws allow the required volume of fuel (these control volume, NOT the mixture), the profile of the screw is somewhat unimportant. Basically, there are two different profiles: (1) the oldest, which is a large angle, short taper, and (2) a newer design, which is small angle, long taper. Rochester started playing with the small angle, long taper screws on some carburetors in the 1950's. The long taper gives the tuner the ability to more finely tune the idle circuit, as changing the volume of fuel requires more rotation of the screw(s). Fast forward to 1968, when Federal Smog Emission became the law of the land, and virtually all O.E. carburetors started using the long taper for more precise adjustment. Rochester was just ahead of their time on this one. Jon.
  13. The throttle body with the 10-47 was used on both the 1922 4 cylinder and 1922 6 cylinder carburetors. It is not unique to either. To determine exactly which carb you have, you need to check other components. Marvel did an excellent job of providing service literature. They printed a 28 page booklet for 1922 that would have come with the car. Jon.
  14. Off the top of my head, the carbs that have the power enrichment circuit also have the accelerator pump. EDIT: In the FWIW category, my favorite aftermarket updraft carb families are the Stromberg SF/SFM series, and the Zenith 63AW/263ME series. The Carter BB series is also good, as long as everyone understands one does NOT pump the footfeed to start the car. Jon.
  15. As to your adapter: Do not know the cost of a 3D printer, but guessing way above my pay grade. While adapters may be machined from a number of materials (cast iron, aluminum, brass, etc.), an easy method of producing an adapter is to acquire two worthless carburetors with cast iron throttle bodies at a swap meet, cut the throttle bodies just above the flanges, and weld the two pieces together. Rochester type B carbs come in both S.A.E. sizes 2 and 3; and make excellent donors if one needs these sizes. Adapters for updrafts should be as short as possible; as the thicker the adapter, the more effect the adapter has on hard starting of the engine. Jon.
  16. Since you did not specify, going to assume this is for the 1926 Chrysler 70 under your username. This would be an updraft carburetor. MOST updraft carburetors that have accelerator pumps use the vacuum accelerator pump FOR SAFETY! The main exception is the Carter BB-1, which I personally rate lower than the Zenith or the Stromberg with the vacuum accelerator pumps. An engine with no more compression than yours doesn't need an accelerator pump. Most folks use the accelerator pump to help start the car (downdraft carburetors). Pumping the footfeed to help start a car with an updraft carburetor and a vacuum accelerator pump results in ankle exercise. Pumping the footfeed to help start a car with an updraft carburetor and a mechanical accelerator pump PUMPS A VOLUME OF FUEL OUT THE AIR INTAKE ONTO THE GARAGE FLOOR UNDER THE ENGINE! IF an engine with an updraft carburetor NEEDS an augmentation of fuel to help start the engine, the choke should be used. A number of updraft carburetors use the accelerator pump in conjunction with the power enrichment circuit. Some of the less-expensive carburetors being sold today do not have the power enrichment circuit, which can lean to issues if one drives in hilly terrain, where wide-open-throttle is needed to climb a hill. Those residing in southern Illinois (where a mole-hill resembles a mountain ) can generally get by without the power enrichment circuit. Jon.
  17. I would hope most see me as a carburetor guy As far as a specific car make/style ????? Maybe a John Deere tractor or heavy truck.....................whatever is required to get the job done! Quoting padgett "my hobby is a continuously evolving process": over the years, have owned and enjoyed tractors, trucks, sedans, roadsters (not any more, I "burn" too easily), hardtops, sports cars, muscle cars, and mini-vans. I will never afford either of my two dream cars (both produced by Jaguar) unless I win the lottery (and I don't play). I just enjoy things mechanical. Jon.
  18. I just noticed the comment "more fuel earlier" in an earlier post on this thread. The Rochester power valves are basically either open or closed; there really is no partial opening. Rochester offered at least 19 different power valves for the 2G and 4G carburetors. There are two different physical valves, 2 different plunger heights, and several different calibrations. The most common calibration (and the valve commercially available) is one with a long plunger and (4) four #54 fuel orifices. The different height plungers were to change the timing of the operation of the valve. Several years ago, we developed a spring kit for the power valve actuator valve, to assist in tuning when the owner had changed the camshaft to a camshaft providing significantly less vacuum. So the valves are adjustable in two dimensions: (1) timing, and (2) fuel orifice size. Jon.
  19. The gasket under the power valve should be a fairly thin fiber washer. Changing the thickness will not effect the total amount of fuel provided by the power valve, but might effect the timing of the activation of the power valve. Maybe by 1 or 2 micro-seconds. Too thick a gasket might cause the valve to always be open, which would be much less than desirable. Rochester themselves used a shorter plunger on many of the power valves to SLOW the timing of the valve, not advance it. I would use the thinner washer. Jon.
  20. If you run across anything printed on the Schebler model O, I would love to see it! The model O seems to be one of the "red-headed step children" of Schebler. My records show it was used only in 1913; AND 1914 CATALOGUES SHOW A REPLACEMENT CARBURETOR! Unfortunately, while I have a 1912 catalogue and a 1914 catalogue; I do not have one from 1913. Jon.
  21. Quote "Brakes, clutch, several rubber parts, difficult carburetor, even had to reseal the steering gear, and worst of all, heater core on an AC car." End quote. Most 1965 Chryslers came with either a Stromberg type WWC or Carter AFB, both of which are excellent carburetors. A few of the base 1965 Chryslers came with Carter type BBD two-barrels, which definitely could be difficult. Jon.
  22. ASSUMING THE CHOKE IS CORRECTLY ADJUSTED, AND COMPLETELY VERTICAL WHEN WARM (if not, fix it). There are two idle mixture control screws (brass screws, with the calibration held by a spring). These control the amount of idle fuel. These should be adjusted from 1/2 to 1 1/2 turn from lightly seated. So, suggestion: (A) with the engine cold, gently screw each idle mixture control screw clockwise UNTIL LIGHTLY SEATED, DO NOT OVERTIGHTEN. (B) record the number of turns for each (C) reset the screws as they were (D) start the engine, and run at a fast idle UNTIL OPERATING TEMPERATURE IS REACHED, maybe 8~10 minutes (E) Turn the throttle positioner about 1/2 turn clockwise which should significantly increase the idle RPM (F) Reset both idle mixture control screws AS FOLLOWS: (F-1) Fresh engine (less than 500 miles) 1 1/4 turns from lightly seated (F-2) Good engine with more than 500 miles 1 turn from lightly seated (you might later wish to try 3/4 turn) (F-3) Engine with multiple thousand miles, low compression, burns oil, should be rebuilt 1 1/2 turns from lightly seated (G) slowly turn the throttle positioner screw clockwise until the desired idle is reached. (H) test drive - you may need to tweak the adjustment. EDIT: typo - (G) should read counterclockwise. Jon. Jon.
  23. It APPEARS to be a 1928 carburetor. There are identifying letters that will prove/disprove this. The 1928 Chevrolet carburetor would have either a "RAKXO" or a "C RAKXO". If either, then we can furnish a rebuilding kit. Jon.
  24. Matt - the adjustment part is toward the bottom. Automatic chokes Jon.