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Everything posted by carbking

  1. When the Rochester Q-Jet came out in 1965, it had several "teething" problems: (A) internal dashpot (fixed in 1966) (can be fixed by professional rebuilder, if he/she wishes) (B) "umbrella" fuel valve (mostly fixed in 1967) (can be fixed with an available kit) (C) press-in well plugs (fixed in 1968 as mentioned by Joe above)' (can be fixed by professional rebuilder, if he/she wishes) (d) (small d) float pin placement (novice rebuilders could break the casting plus not ideal for high performance work) (fixed mostly by 1971) And an on-going issue, like virtually all "modern" carburetors, an aluminum throttle body that normally requires primary bushings to be installed after some 50k~80k miles. Overall, a wonderful street carburetor that can also easily be adapted to straight-line racing. Jon.
  2. I forgot to mention (senior moment? ) that floats may also be machined from Balsa wood. Again, the float must be sealed after the arm is affixed to the float. Jon.
  3. Model airplane dope, or POR-15 may be used to seal a NEW (never been placed in fuel) float. We were unsuccessful when we experimented trying to re-coat a used float. I am unaware of a brass float for this application, although we have a few left for earlier Marvels (replacing Marvel 30-504). We started machining Marvel floats from the closed-cellular polynitraphyll foam maybe 30 years ago. The reason: we could find no source for natural cork in quantities that were economically reasonable. The cork we could buy was "recombined" cork. Recombined cork was the scraps of natural cork from those who used the natural cork, ground, and a filler added to glue the crumbs together. IT DOESN'T FLOAT! We suggest to our customers that the foam float SHOULD be sealed, after the float arm is installed on the float. Jon.
  4. The U5 is a later carburetor. The serial number (yes, in that era carburetors were serial numbered) 223631 follows the U-5. The record of first usage of the Zenith type U in my database is 1921. Kelly-Springfield started using the type U in 1923, again, according to the information in my database. The U-5 would not bolt to the 1916 intake manifold. Is it possible your truck has been repowered? We do offer a rebuilding kit for the U-5, but it is one that is made to order, and we are currently swamped with orders. Seems we stay that way most of the time. Phone number is in my signature. Jon.
  5. From the pictures, it appears that the governor is a "sandwich" governor. That is, the governor is "sandwiched" between the carburetor and intake manifold. We have no information on governors this early, and very little period. The Zenith documentation indicates that Kelly-Springfield used a Zenith type L-4 carburetor. Difficult to tell from the pictures, but the carb doesn't look to me like a type L; more like a type O. In any event, the type and size will be cast on the side of the carburetor. Often, this identification is on the side closest to the block, and the carburetor must be removed to see the identification. "Clean out kits" (gaskets, fuel valve, fiber washers, body screws) are probably available if you are not in a hurry, but will not know until the exact type of carburetor is known. Once you can see the identification (in letters and numbers about 5/16 inches tall), it will appear as a letter (or maybe two) representing the type of carburetor, followed by a number representing the size. Example "L4" supposedly original, or "O4" which the picture resembles. The numbers on Zenith carburetors do not correspond directly to an S.A.E. size, but do IF you make the correction. To get the S.A.E. carb size from the Zenith number, subtract 3 from the number. Thus an L4 would be an S.A.E. size 1. An O5 would be an S.A.E. size 2, an L8 would be an S.A.E. size 5. The following information is copied from an article on my website: Carburetor sizes – 1 barrel The Society of Automotive Engineers developed standards for carburetor physical sizes. The more common sizes found on automobiles are listed below. Bore size is listed as approximate, as some carburetors were much more efficient than others. Nominal ½ inch or 5/8 carburetor, center to center 1 13/16 on mounting bolts, bore size approximately 13/16 inch. Nominal ¾ inch or 7/8 inch carburetor, center to center 2 ¼ on mounting bolts, bore size approximately 1 1/16 inch. Nominal 1 inch carburetor, center to center on mounting bolts 2 3/8, bore size approximately 1 3/16 inch. (Often referred to as size 1). Nominal 1 1/8 inch carburetor, center to center on mounting bolts 2 3/8, bore size approximately 1 5/16 inch. Nominal 1 ¼ inch carburetor,center to center on mounting bolts 2 11/16, bore size approximately 1 7/16 inch. (Often referred to as size 2). Nominal 1 3/8 inch carburetor, center to center on mounting bolts 2 11/16, bore size approximately 1 9/16 inch. Nominal 1 ½ inch carburetor, center to center on mounting bolts 2 15/16, bore size approximately 1 11/16 inch. (Often referred to as size 3). Nominal 1 ¾ inch carburetor, center to center on mounting bolts 3 5/16, bore size 1 15/16 inch. (Often referred to as size 4). Nominal 2 inch carburetor, center to center on mounting bolts 3 9/16 inch, bore size approximately 2 3/16 inch. (Often referred to as size 5). Get the identification from the carburetor, and I can probably give more specific information. Jon.
  6. Carburetor icing is more often the result of the carburetor being adjusted too rich. If the venturi is too small, the carburetor will run rich. Jon.
  7. You can always try tapping further into the hole, and using a longer screw; but if that fails (opinion) the heli-coil is the best option. Jon.
  8. Everyone has their own method. I use an empty mustard squeeze bottle that I fill with fresh fuel, and fill the carburetor bowl through the bowl vent. Or, in the case of various lawn & garden tractors, tillers, weed eaters, etc., that have sat all winter; a small psssst of starting fluid. Jon.
  9. This actually makes the issue worse! You are pumping fuel from the bowl as the fuel pump is trying to fill the bowl, but not enough to cause the engine to start. Jon.
  10. Garry - the issue now becomes "which UUR-2 is the repop"????? Stromberg made at least 102 different type UUR-2 carburetors. Without referring to the prints, I can think of at least three DIFFERENT bowls, and four DIFFERENT bowl covers. They are NOT interchangeable. There at least two different styles of large venturii. Not trying to throw cold water on your parade, but without knowing EXACTLY what you have, impossible to answer your question. Try to get the exact part number for the repop you purchased from the repopper, and then maybe. Otherwise, your local carburetor restorer that has knowledge of these carbs, and a machine shop is your best answer. Jon.
  11. Have never tested the Offie against an original Buick 2x4. As a general rule (opinion), the Offies of this period were the best of the aftermarket intakes, at least for performance street use. General rule number 2: the aluminum aftermarket intakes lost weight, and power, when compared to original. However, dual quads, when properly set-up WILL out-perform a single quad, and are WAAAAAY better than the eye-candy tripowers. As to the ebay link (not mine, I wouldn't sell them that cheap) being stupid prices; try putting a set together using current production "stuff" that will perform as well for less. Jon.
  12. I have quite a few Carter carburetors for Chevrolet, some original equipment, others the popular YF replacements. These are cores that I planned to rebuild, but way too busy to rebuild, even my own carburetors. So offering these for sale as is, with one of our major rebuilding kits.Some of these are actually rebuilt by someone else, some are used cores. All will be sold as cores, with the major rebuilding kit. Some of these I have more than one. Once I sell out of a number, I will not be acquiring more. All will have throttle and choke shafts which turn freely, nothing is seized.Prices listed below include postage to all addresses in the 48 contiguous United States. When comparing prices, remember that our 100 percent USA major overhaul kits are approximately $80~85, and postage is going to be in the $20~25 range, so take these into account.W-1 carbs:420s - $300.574s - $325.Also have many earlier W-1's which are totally restored, and priced accordingly. CALL on these.YF carbs:756s - $250.787s - $250.788s - $350.789s - $300964s - $250.965s - $225.966s - $350.2100s - $400.965s - new old stock in original Carter box - $400.MasterCard/VISA accepted without penalty.Trades: NO carburetors, cars, or car parts wanted (with 150,000 carbs, I just don't need more ) Will consider trades for U.S. gold and silver coins. No other coins or anything else considered.Here is a link to my website showing applications of the YF carbs: (9-12, 1-4 Mon-Tues central time).Jon.
  13. Please consider this ad as ended, the book is now on Ebay. Jon.
  14. Bernie - not much on conspiracy theory myself. However, if one does the math: According to Google, the U.S. consumed 140.43 billion gallons of gasoline in 2015 (latest year). If you average my figures on fuel mileage conservatively at 93 percent (since there are many more fuel injected vehicles, I feel this figure is low, but will serve to illustrate my point); then an extra 11.5 billion gallons of gasoline was consumed in 2015. Federal gas tax is 18.4 cents per gallon. This represents more than a 2 billion dollar tax increase! Whether it was planned than way or not is certainly open for debate; but betcha some of the politicians have thought of it Jon.
  15. Joe - some of the carburetors I had recalibrated for the E-10, others no. On fuel economy, didn't seem to matter a lot (maybe 1~2 percent). Power difference could be noticed. What I did not do, which would probably have gotten a bit of the mileage back, was to install an electronic knock sensor for the distributor, so the distributor could advance to compensate for the higher AKI of the ethanol. Since the AKI of the ethanol is so much different from the AKI of the gasoline, I didn't want to advance the timing looking for the optimal spot, and risk the engine to detonation. The higher compression engines burned more of the ethanol, basically losing only the difference in energy. Higher compression engines I tested were Ford 390GT, and Pontiac RAIV. I am convinced that the lower compression engines spit part of the ethanol out the exhaust unburned. Jon.
  16. I understand the arguments for and against this being a subsidy for farmers, and as Joe mentioned, buying votes. However I believe there is another reason the government is pushing ethanol - a veiled MAJOR tax increase! I have done LOTS of testing on E-10, although with no vehicles newer than about 2006. My findings on fuel economy E-10 versus E-0: Low compression carbureted engines - average 91~92 percent Medium compression carburetor engines - 92~94 High compression carbureted engines (10:1 or higher) - 94~95 percent Fuel injected engines (with O2 sensor technology) - 84~86 percent (NOT a misprint! my testing shows fuel injection with O2 much worse than carburetors in handling the E-10) Again, have done NO testing with current production efi engines. But if one looks at the above percentages, how many additional gallons of fuel will be used nation-wide, and how much federal tax will be collected on the additional usage? And how much more with E-15? Jon.
  17. One thing that will possibly help is the reluctance of the public to buy this *&^%, IF it is not required. When E-85 came out, every local station carried it. Today, I don't know of a station within 30 miles that carries E-85. It simply will not sell! A few years ago, it was virtually impossible to purchase undiluted gasoline in central Missouri except at a marina. Today, virtually every station, while still having one or more E-10 pumps, will offer real gasoline in a variety of octanes. The general population quickly learned the cost of E-10. Guessing most of them will have to be forced to use E-15. Jon.
  18. No - it isn't. But lots of early carbs are virtually impossible to modify inexpensively. How proficient are you at winding custom airvalve springs???? After you design the desired tension? Right now (don't know how long it will last) there is a tremendous market for good carburetor rebuilders/modifiers. We are so busy with the manufacture of rebuilding kits, we simply do not have time, and turn down 20~25 rebuilding jobs weekly. Hopefully, some youngster of 40~45 or so will get involved. Jon.
  19. While most on this forum will initially be concerned with their older cars, the real loser will be air-cooled small engines. I have posted before the advantage of E-10 for my lawn and garden tractor. This is a fuel injected John Deere 20 HP. With E-10, it just isn't happy if the ambient is 85~90 or above and the sun is shinning. Thus "Honey, I will have to watch the ball game, the mower won't run"! It will run just fine at 100 (I don't, but the JD will) if undiluted gasoline is used. I have no idea what it will do on E-15. Maybe I will have to mow at night??? Or use one of my older carbureted JD's that I can modify. For those with 1932 and newer vehicles with downdraft carburetors, Carter carbs are an excellent choice because of the metering rod technology. Carry a set of rods in the glove box for gasoline, E-10, and E-15. The rods are quite easy to change on most models. And while I do not recommend doing this in practice; to prove the point of easy change, I once changed a set while the engine was running at idle. On the older vehicles with updraft carburetors, the ones that will give the most trouble will be those that were advertised in the day as "automatic". Most of the airvalve carbs fit this category because the airvalve spring is calibrated for a specific energy content, and there is little adjustment on the tension. Examples: Cadillac (Johnson), Packard airvalve (Detroit Lubricator), Marvel (other than early GMC), Schebler, Johnson, Rayfield, etc. The "plain tube" style (Stromberg, Zenith, etc.) can easily be tuned. Jon.
  20. (1) Compression test - if bad STOP and address the issue (2) Assuming compression was good - ignition test - points (if needed), set dwell, set timing (set dwell FIRST) (3) Since you have played with the mixture screws, try suggested initial setting - in until thumb tight, then out 2 1/2 turns. (4) Start, warm to operating temperature, then test vacuum at idle. Assuming you have the original carb, it is the least likely of everything to be the problem! Jon.
  21. A compression test might give some insight as to your compression ratio. Assuming your compression is decent, LOTS of HP can be made using the 7028244 carb. Acquire the book on modifying Q-Jets written by Cliff Ruggles. An 800 CFM would be better, but NOT because it is 800 total CFM. The primary side of the 750 is 150, while the primary side of the 800 is 200. GM found that the transition from primary to secondary was smoother with the 200 primary. Jon.
  22. Here is a picture of the bottom of the throttle body of a Compound Carburetion rear carb: Note the presence of idle mixture screws. The rear carb was not a "complete" carburetor. The rear carb has an idle circuit, and a main metering circuit. It does not have a choke circuit, a pump circuit, or a power circuit. The two existing circuits work exactly as they would in a complete carburetor. Stromberg suggests an idle mixture setting of approximately 1 turn on EACH of the two carbs. Note that the throttle plates are designed to completely close. Thus, ASSUMING that the carburetor is correctly adjusted, and the progressive linkage is correctly adjusted, NO FUEL would flow through the main circuit with the damper removed, UNTIL the progressive linkage was opened sufficiently far to allow the throttle blades to open. After the throttle blades started to open, fuel would flow proportionally to the air velocity through the main venturii. The damper assembly is in place, not to prevent overfueling, rather to prevent (or minimze) a significant hesitation because of an instantaneous lean condition if the rear (secondary) carburetor is opened before the engine RPM is sufficient to accept the additional AIR. If the damper is NOT present, fuel flow still would not start from the rear carb until such time as the progressive linkage actually opened the rear carb throttle blades. Jon.
  23. If the car is still together, run three 0-60 times and get an average. Once the modifications are done, do the same thing, and compare the results. You may be surprised. Jon.
  24. How and what one does often is a function of one's budget, AND the guy at the local speed shop that wants to help one with one's budget Street engines, and engines for trailered race-cars are two different items. The rest of this post is directed toward a street engine. Three external (read less expensive than internal) options are: (A) carburetion (maybe), (B) distributor, and (C) exhaust. Covering the distributor first - most of the US V-8's by 1972 had very little initial advance, and a distributor that cranked in the rest. Not a distributor guy, so will leave specs to those that are; but more initial advance (up to a point) is generally a good thing. Willis (NTX5467) covered the exhaust. As far as the carburetor/intake manifold: Lots of early 1970's Buick carbs were 800 CFM, and the Pontiac and Chevy dudes have been migrating them to Pontiacs and Chevvies for years. The fact that the WOT is 800 is nowhere near as important as the fact that the primary side is 200 versus 150 for the 750 CFM carbs. When Carter brought out the TQ in 1969 (race-only), and folks used them on performance street-cars, it was found that the transition from primary to secondary was MUCH smoother using the slightly larger primary. Buick figured that out in 1970, and Pontiac performance engines used larger primary carbs beginning in 1971. By 1976, virtually all of the Q-Jets were 800 (200/600). For street use in street RPM ranges, the aftermarket intakes will gain style points, AND LOSE LOW-END TORQUE! Your choice, style or torque. So, suggestions: (A) carburetor - determine if yours is a 750 or 800. If 750, acquire an 800 (Q-Jet or the Carter GM TQ). If you go with the Q-Jet, buy Cliff Ruggles book on the Q-Jet. (OPINION) NOTHING new will outperform either of these two on the street, and probably won't come close unless set up by a professional. (A-sub-a) manifold - stock Buick (B) distributor - talk to a distributor dude, nothing wrong with a modified (curve) GM original. (C) exhaust - 2 1/2 inch pipes, and good mufflers. Personally, I DETEST tube-headers on the street (really like to be able to listen to music). The above should be good for a healthy performance increase, and won't bust the budget. Have fun. Jon.
  25. Quote Valk "That's what my rear damper looks like - valves and counter weight removed. Told the damper was obsolete given today's modern fuel. " Modern fuel should have nothing to do with determining whether or not to use the damper. If an original set-up, with the "dumper" rear carb, and progressive linkage - use the damper. If the set-up has been converted to two "complete" carbs (the "dumper" carb is not complete), and straight linkage - the damper should not be used. Have NEVER experimented with the original set-up (dumper, progressive) without the damper, so GUESSING! I would expect, ASSUMING THE REAR CARB AND THE PROGRESSIVE LINKAGE ARE CORRECTLY ADJUSTED, that the system would run lean, not rich. Most newer, V-8 engines with multiple carbs had a lockout to prevent the secondary carbs from opening before a certain RPM, thus flooding the engine with air and creating a lean condition. Jon.