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| | | Forums66 Topics128,072 Posts1,055,906 Members48,429 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: May 2010 Posts: 74 'Bolter | | 'Bolter Joined: May 2010 Posts: 74 | There seems to be some debate. There are 2 check balls in the rebuild kit, a larger one and a smaller one. Which one goes in the accelerator pump well, and which one goes in the pump discharge?
I'm prepared for the jokes as well as the answer... | | | | | Joined: Jan 2010 Posts: 38 New Guy | | New Guy Joined: Jan 2010 Posts: 38 | I would like to know the answer to that question. I rebuilt mine and had the same issue. Now it doesnt run without the choke on. once the choke is off it back fires and shuts off. Its also hard to start. I have taken the carb back apart and switched the balls around and have the same problem. Is yours doing the same thing?
If it's broke hit it harder!
| | | | | Joined: May 2010 Posts: 74 'Bolter | | 'Bolter Joined: May 2010 Posts: 74 | no, my problem is a little different. I can get it started just fine, but after a few minutes it starts sputtering and I can't keep it running. I don't think my problem is related to the check balls, but I did rebuild the carb, and just wanted to make sure I put them in the right places.
I'll be checking the vacuum hoses coming off the carb, and also maybe putting on a new fuel pump, hoping something will fix it. | | | | | Joined: Nov 2002 Posts: 2,766 Carburetion specialist | | Carburetion specialist Joined: Nov 2002 Posts: 2,766 | Some Rochester 2GC carbs use two balls, others one only. Would be easier to give an intelligent answer if the identification number of the carburetor were given.
However, since that is not present, "shotgunning" the answer:
All of the 2GC series carbs that I have personally worked on had the larger steel ball under the venturi cluster.
Those that I have worked on that have a ball under the pump use the smaller aluminum ball under the pump.
It is possible that a siphoning action could occur if the smaller aluminum ball were placed under the venturi cluster, thus artificially enrichening the mixture causing the engine to stall from an overrich mixture.
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: May 2010 Posts: 74 'Bolter | | 'Bolter Joined: May 2010 Posts: 74 | hmmm carbking, thanks for the answer. The carb did not have the tag, so I don't have the id numbers. I didn't think the balls could make that difference, but from what you say, that might be part of my problem after all. The first instructions I had said that the bigger ball went under the pump, but then I was told the opposite and wanted to confirm it. Guess its time to pull the carb and switch them. | | | | | Joined: Jun 2008 Posts: 1,644 'Bolter | | 'Bolter Joined: Jun 2008 Posts: 1,644 | John,
I've got the pump figured out, but where is the "venturi cluster" and what does it look like?
Thanks.
Chuck 1950 Chevy 1/2 ton (all original) 1951 Chevy 1/2 ton (future streetrod) 1941 Chevy coupe 1938 Chevy coupe streetrod | | | | | Joined: Jun 2008 Posts: 1,644 'Bolter | | 'Bolter Joined: Jun 2008 Posts: 1,644 | I believe I have a model "B". Could you provide an exploded view of that model please?
Many thanks!!
Chuck 1950 Chevy 1/2 ton (all original) 1951 Chevy 1/2 ton (future streetrod) 1941 Chevy coupe 1938 Chevy coupe streetrod | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | | | | | | Joined: Jun 2008 Posts: 1,644 'Bolter | | 'Bolter Joined: Jun 2008 Posts: 1,644 |
Chuck 1950 Chevy 1/2 ton (all original) 1951 Chevy 1/2 ton (future streetrod) 1941 Chevy coupe 1938 Chevy coupe streetrod | | |
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