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Everything posted by carbking

  1. Difficult to be certain from the picture, but the downdraft carburetor appears to be a Rochester type B, introduced in 1950. Jon.
  2. The carburetor and fuel pump rebuilding and testing station on my site had testing procedures and tools for service (volume, fuel leaks, vacuum leaks, etc.). The carburetor companies testing with the wet flow bench did NOT use fuel (dangerous). There is another non-flamable material (no, I do not remember its name) with properties (other than the ability to burn) simiilar to gasoline that is used with the wet flow bench. I have custody of the Carter Carburetor Company flow test files. Lots of folks consider "flow testing" as to determine the CFM of the carburetor; but f
  3. Are you located in Canada finding 94 octane? Remember, the octane ratings scales used in Canada differ from those in the USA. The posted Canadian rating for the exact same fuel will be several points higher than the posted US rating. Jon.
  4. Pictures in my "virtual carburetor museum": Hygrade carburetor and fuel pump repair and test station Jon.
  5. The pressure build-up is due to expansion of fuel in the fuel line between the regulator and the carburetor. I have been suggesting the use of the return line for 30 years. I didn't invent the idea, just looked at what the manufacturers did 50 plus years ago on vehicles with big engines and air conditioning. The factory engineers were not dummies. Often a good idea to see how they solved a problem, and see if their solution may be migrated to a similar problem. Jon.
  6. I have no first hand experience, other than personally never needing to do so, thus - no comment. Jon
  7. Dynaflash - if you stop for gas (or any time you restart the engine when the engine is hot), run the engine at a fast idle (1500~1800 RPM) for 30~45 seconds BEFORE you put it in gear. You are experiencing "hot soak". Once you clear the fumes in the air cleaner, and the puddles in the intake manifold, the engine should run as it did before you shut it off. Jon.
  8. If you are truly concerned about the long time damage: These are NOT rare carburetors, as the Riv used the same carb as other 455's (7043240). Pick up one (or more), rebuild it/them (I happen to know of an excellent source for ethanol-friendly rebuild kits ), and put them on the shelf for the future. Change the soft fuel hose(s) every five years. Drive and enjoy the vehicle. Jon.
  9. Ethanol and higher octane BOTH matter, to a certain extent. Ethanol has less energy than gasoline, so might require carburetor recalibration. It DOES effect non-leather accelerator pumps, as well as soft fuel lines in vehicles not frequently driven. Over a long time (25~30 years or so), it can cause damage to aluminum or zinc alloy carburetor bodies. Repeat, this is a LONG-TERM effect. Too high octane fuel will not completely burn in an engine designed for lower octane, without timing and possibly (depending on the compression ration) compression changes. So
  10. Additional information: The gasket posted by KongaMan is for a square-bore, but the heat channel in this gasket is the same heat channel used by Buick on the 1967 430. Note the difference in the heat channel in this gasket versus the pictured Corvette gasket. The gasket itself, obviously, is different. Jon.
  11. Additional information by the OP would have been useful, but since not present, will "scattergun" this post: Four different "original" Rochester quadrajet (Q-Jet) carburetors might be found today on a 1967 430 Buick: 7027240 (early production - Federal cars) 7027241 (California cars) (all you folks that believe the "odd last number = standard transmission" - take note of this number) 7027248 (late production - Federal cars) 7041305 (service replacement carburetor produced first in 1971) ALL of these carbs were specified to use flange ga
  12. As far as the carburetor is concerned: Find the gauge, and set the carburetor to standard setting; then, and only then, you have a repeatable baseline. Until then, you are guessing! The white tailpipe that was once a sign of a well-tuned engine...............................was lead residue! The tailpipes on my OT newer factory fi vehicles are brown/black in color. Fuel economy is definitely NOT all carburetor. Here is an article I did a few years ago: http://www.thecarburetorshop.com/Troubleshooting.htm#Fueleconomy Others
  13. My first thought is to test the ignition switch. It may be making contact in the "start" position, but not in the "run" position. Jon
  14. NOT cold starts? There is no heat when the engine is cold Not going to help starting. The ports are there for driveability in cold weather or cool humid weather. And as far as plugging the holes in the intake are concerned: I KNOW we are talking about Buicks on a Buick forum, but folks get here by using "search" as well as just reading the forum. Lots of folks think of blocking the entire crossover, not just the holes. Some gasket manufacturers actually supply intake manifold gasket to block the entire crossover. So just wanting to nail this down to a speci
  15. Joe - great testing! I believe you will find the missing heat shield to shield the carburetor bowl is the culprit. I have not seen this particular one, but generally, these were simply a portion of a sheet metal "box" that would surround the carburetor bowl with maybe a 1/4 inch air gap from shield to bowl. The lower end of the box would have an extension that generally had a hole that fit over one of the carburetor mounting bolts, and could thus be installed with the carburetor. Jon.
  16. Check this link to the troubleshooting section of my website: Fuel leak at throttle shaft when hot Jon
  17. "High octane (99 and 101) unleaded E10 is readily available near me." If this is U.S. octane, way too high for a '73 Riv. If Canadian octane, do a search on RON, MON, and AKI. I'm with Matt on driving more, and keeping fresh fuel in the carburetor. If one will start one's vehicle once a week, and move it at least twice the circumference of a tire, one will have far fewer service issues. I don't agree that non-leather accelerator pumps are ethanol-resistant UNLESS one does drive sufficiently often to always keep fuel in the carb. If allowed to dry out, they t
  18. Carburetor alternatives? There are quite a few Carter type AFB, and Rochester 4-GC four barrels, depending on the year. There is also a Rochester 2-barrel available. If you are looking for a new shiny carburetor that you can order from one of the online vendors, that doesn't require major butchery to work well on the Buick; I am unaware of a single one. Jon.
  19. It really isn't difficult to make the e-clone function in a Buick. All you have to do is remove the nailhead and transmission, and install a small block Chevy with a TH400. Now you can install the e-clone Jon
  20. Don't even think about the possibility of considering trying to weld that zinc alloy! Yes, I know there are special rods; yes, I know there are folks that claim they can weld this stuff. We had some junk pot metal carburetor parts from this era for test purposes. We tried the special rods. We also tried a number of the folks that claimed to be able to weld pot metal. For the stuff we tried to fix, and the stuff "fixed" by the "experts" we subjected to an artificial heating/cooling cycle test (similar to the heating/cooling of an engine component). ALL failed
  21. Turn the carburetor upside down, and you will see the "hole" is a fresh air intake for the starter switch. Jon.
  22. The only two recommendations that I have would be: (1) internal bypass (2) range that can be adjusted for the maximum pressure for which the carburetor is designed. Jon.
  23. Your shop manual should tell you that your carburetor wants 3 psi MAXIMUM! More than that, and results are going to be less than desirable. Yes, the carburetor CAN be modified (on the inside, by an expert) for a bit more pressure, but it is a tricky procedure and would require lots of time, effort, and parts. As to a regulator, you want a regulator with an internal bypass, NOT the inline dial-type sold by the FLAPS in the $19.95~$39.95 (depending on the conscience of the seller). These are quite useful for those of us who garden, have a strong arm, and the t
  24. Stromberg used lead balls as plugs to seal access passages in the castings. If you do not need to remove the old plug for cleaning the passage, just ignore it. And item 26 in the picture is a check valve, which is a brass threaded fitting with an encapsulated steel ball. We include the passage balls in most of the Stromberg kits, because the balls cost us about 4 cents each, and postage, in the rare case someone actually needs one, is $12. Simply cheaper to include them. The vendor should have explained this to you when you contacted
  25. The original carburetor would have been a Penberthy (Ball & Ball) SV-37. In almost 60 years of working on carburetors, I have yet to see a usable SV-37. Enthusiasts that wish to enjoy their cars replace them. As noted in the post above, Zenith made replacement carbs for many makes and models. Jon.
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