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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Aug 2004 Posts: 1,418 ODSS Lawman | | ODSS Lawman Joined: Aug 2004 Posts: 1,418 | I have a pair of Carter YF’s that need some work. Work that is beyond my tools and knowledge. Years ago there were several folks to send these to but they have since retired.
So who’s out there?
SWEET Sergeant At Arms: Old Dominion Stovebolt Society BUNS?!?!?!Where we're going, we don't need no buns.....1950 GMC 450 1951 Chevy 1/2-TonThe GreenMachineIn the Stovebolt Gallery | | | | | Joined: Mar 2010 Posts: 10,305 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,305 | That is an easy carburetor to rebuild. What kind of work are you thinking about?
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Nov 2002 Posts: 2,770 Carburetion specialist | | Carburetion specialist Joined: Nov 2002 Posts: 2,770 | Good rebuilding kits are readily available.
The carbs rarely need any machine work.
And as Carl stated above, easy carburetor to rebuild. The key is to get the correct parts in the rebuilding kit.
As far as tools are concerned:
(A) Straight-bladed screwdriver in two blade widths (B) Ruler (C) Homemade (a.k.a. poor-man's) ultrasonic cleaner (3 pound coffee can with a mixture of water and Dawn dishwater soap), and a heat source (a.k.a. stove) to boil the water.
As far as knowledge:
I believe my Granddaughter could rebuild one, and I know my Wife and Daughter could.
Go for it!
Jon. Good carburetion is fuelish hot airThe most expensive carburetor is the wrong one you attempt to modify. If you truly believe "one size fits all," try walking a mile in your spouse's shoes!The Carburetor Shop | | | | | Joined: Mar 2014 Posts: 4,509 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,509 | I agree with Jon 100%. Not a difficult one to rebuild. Of 5 I checked late last summer, a couple had warped air horns, however. I didn't expect that, but it was not hard to remedy. Let me know if yours need help.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
| | | | | Joined: Aug 2004 Posts: 1,418 ODSS Lawman | | ODSS Lawman Joined: Aug 2004 Posts: 1,418 | The biggest issue I have is where the throttle linkage connects to the base of the carb. That pivot has worn and leaks like crazy. That’s the area I’m looking for help on.
SWEET Sergeant At Arms: Old Dominion Stovebolt Society BUNS?!?!?!Where we're going, we don't need no buns.....1950 GMC 450 1951 Chevy 1/2-TonThe GreenMachineIn the Stovebolt Gallery | | | | | Joined: Nov 2002 Posts: 2,770 Carburetion specialist | | Carburetion specialist Joined: Nov 2002 Posts: 2,770 | The biggest issue I have is where the throttle linkage connects to the base of the carb. That pivot has worn and leaks like crazy. That’s the area I’m looking for help on. Probably a political problem, not a carburetor problem.  Find someone that has a digital caliper, and measure the clearance from the throttle shaft to the throttle body. If it exceeds 0.010 (10 thousanths) inch, then probably may be repaired with a new throttle shaft. New old stock shafts may be available, depending on which YF. I don't remember ever doing a Carter YF with excessive clearance. Very rare. Check this link: Fuel leak by throttle shaftJon.
Last edited by carbking; 03/12/2019 12:53 PM.
Good carburetion is fuelish hot airThe most expensive carburetor is the wrong one you attempt to modify. If you truly believe "one size fits all," try walking a mile in your spouse's shoes!The Carburetor Shop | | | | | Joined: Mar 2010 Posts: 843 Shop Shark | | Shop Shark Joined: Mar 2010 Posts: 843 | "If it exceeds 0.010 (10 thousanths) inch, then probably may be repaired with a new throttle shaft."
Good morning Jon.
With a clearance approaching 0.010" does a lot of air come in along the throttle shaft due to engine vacuum making idle inconsistent and hard to adjust? I notice the Weber carbs have actual seals at the throttle shafts.
Ray
| | | | | Joined: Nov 2002 Posts: 2,770 Carburetion specialist | | Carburetion specialist Joined: Nov 2002 Posts: 2,770 | "If it exceeds 0.010 (10 thousanths) inch, then probably may be repaired with a new throttle shaft."
Good morning Jon.
With a clearance approaching 0.010" does a lot of air come in along the throttle shaft due to engine vacuum making idle inconsistent and hard to adjust? I notice the Weber carbs have actual seals at the throttle shafts. Depends entirely on how the engineers designed the carburetor. Carter designed for minimum 0.004~0.006. An additional 0.003-0.004 wear is normal. Remember that 0.010 cold will be less than 0.010 hot. Don't know about Webers. Jon
Last edited by carbking; 03/12/2019 5:31 PM.
Good carburetion is fuelish hot airThe most expensive carburetor is the wrong one you attempt to modify. If you truly believe "one size fits all," try walking a mile in your spouse's shoes!The Carburetor Shop | | | | | Joined: Nov 2002 Posts: 2,770 Carburetion specialist | | Carburetion specialist Joined: Nov 2002 Posts: 2,770 | I had a telephone call when posting the above, and had to finish before I was finished.
Yar mentioned seals on Webers. I have done very few Webers, and since I am no longer restoring carbs, will never do another; so do not have a lot of knowledge about their construction.
I do know that Holley tried Teflon seals on throttle shafts on 4150's and 4160's for a few years, and then I believe they were discontinued. But the Teflon seals created a TREMENDOUS market for throttle shafts!
WHY?
The Teflon seals wore out in 20k~30k miles (we put the seals in our rebuilding kits for this reason). But to replace the seals, the throttle shafts must be removed. And do-it-yourselfers often would destroy the throttle shaft by twisting off all of the throttle plate screws. The old "law of unintended consequences". Some jobs are just best left to a professional.
Jon. Good carburetion is fuelish hot airThe most expensive carburetor is the wrong one you attempt to modify. If you truly believe "one size fits all," try walking a mile in your spouse's shoes!The Carburetor Shop | | | | | Joined: Mar 2010 Posts: 10,305 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,305 | It would seem to me that some air entering through the minor gap at the throttle shaft would have been accounted for when the carburetor was designed. As the shaft wears somewhat (minor wear), would adjusting the mixture screw address the minor increase of air leaking past the shaft? I am talking about minor wear, not wallered out. (Jon, you are from Missouri. You know dag gum well "wallered" is a real word.  ) Carl
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | Larry Isgro (as shown in his website URL)
Excellent advice Mike. No BS from Larry. He does good/fast work and “stands behind it”.
He has done A-D and ND Chevrolet and GMC carburetors for me. | | | | | Joined: Jun 2001 Posts: 793 Bondo Artiste | | Bondo Artiste Joined: Jun 2001 Posts: 793 | I've had great luck with Larry Isgro in the past. I'd certainly try him again.
~ Phillip 1949 GMC Suburban - 10 year project 1952 Pontiac Chieftain Convertible straight 8 hydramatic 1945 GMC half ton truck - Driver- Sold 9-15-25 1946 Chevy COE - SOLD 1-5-26 BUH BYE CHEVY! 1959 GMC Half ton long bed NAPCO | | | | | Joined: Aug 2018 Posts: 351 'Bolter | | 'Bolter Joined: Aug 2018 Posts: 351 | There is a fellow - Hal Houghton - in upstate NY (Schenectady) who does rebuilds, up to and including restoration quality. I've not used his services, but I have used several of his fuel pump kits which are high quality, and I've chatted with him quite a bit. He's another one of us who has been around these engines and their components for 50+ years. While I don't have direct experience with his rebuilds, he seems a good resource. Check out Classic Preservation Co if interested.
Last edited by drdoug; 03/13/2019 4:08 PM.
| | | | | Joined: Mar 2010 Posts: 843 Shop Shark | | Shop Shark Joined: Mar 2010 Posts: 843 | "Depends entirely on how the engineers designed the carburetor. Carter designed for minimum 0.004~0.006. An additional 0.003-0.004 wear is normal. Remember that 0.010 cold will be less than 0.010 hot."
Jon,
Thanks very much for explaining that. I've put bushings in some of the carburetors I've worked on to minimize the throttle shaft gap "Because I can". After doing that it seemed like the carburetors responded more positively to idle mixture adjustment.
What I've just learned from you is that my perceived "improvement" is probably yet another example of the placebo effect. Or said another way "I wouldn't have seen it if I hadn't believed it".
Ray
| | | | | Joined: Aug 2004 Posts: 1,418 ODSS Lawman | | ODSS Lawman Joined: Aug 2004 Posts: 1,418 | Had a great chat with Larry this afternoon. It has been a while since I've spoken to him.
Glad he is still around!
SWEET Sergeant At Arms: Old Dominion Stovebolt Society BUNS?!?!?!Where we're going, we don't need no buns.....1950 GMC 450 1951 Chevy 1/2-TonThe GreenMachineIn the Stovebolt Gallery | | | | | Joined: Nov 2002 Posts: 2,770 Carburetion specialist | | Carburetion specialist Joined: Nov 2002 Posts: 2,770 | Ray - the pre-1968 carburetors were less responsive to adjustments in the idle mixture screw(s).
With the beginning of Federal smog emission requirements in 1968 (California was 1966), most of the carburetor manufacturers changed the taper on the idle mixture screw. Take a look at a screw from the 1970's, and compare the taper to the 1950's. The longer taper smog screws are much more responsive, and one can obtain a more consistent idle with these longer tapered screws. Of course, the manufacturer changed the taper for easier adjustment for smog emissions.
Jon. Good carburetion is fuelish hot airThe most expensive carburetor is the wrong one you attempt to modify. If you truly believe "one size fits all," try walking a mile in your spouse's shoes!The Carburetor Shop | | |
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