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| | | Forums66 Topics128,069 Posts1,055,890 Members48,428 | | 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: Feb 2003 Posts: 218 Shop Shark | | Shop Shark Joined: Feb 2003 Posts: 218 | I'm installing a H/W 2bbl on my 250 Chevy. Is the insulator necessary when using the stock manifold, 1 to 2bbl adapter, etc?
Thanks | | | | | Joined: Nov 2001 Posts: 122 Shop Shark | | Shop Shark Joined: Nov 2001 Posts: 122 | I had one on my '54 GMC 248 (don't have it any more). I looked at some pictures I had of it and it looks like I had an insulator on it...check it out... [IMG] http://i45.photobucket.com/albums/f65/caninelaw/carb4.jpg[/IMG] | | | | | Joined: Feb 2003 Posts: 218 Shop Shark | | Shop Shark Joined: Feb 2003 Posts: 218 | Yes, I see it. The insulator I have is with four holes for I suspect, mounting the carb on a 2 bbl. manifold. Perhaps the insulator from the original 1 bbl. Rochester would work where yours was.
You don't remember if you had to, or how you set your electric choke, do you? Mine is not closing completely when cold.
Thanks! | | | | | Joined: Oct 2005 Posts: 1,317 Shop Shark | | Shop Shark Joined: Oct 2005 Posts: 1,317 | I've run both the Holley/Weber and a pair of Carter/webers on the adaptors on my 235's with no additional insulators and have experienced no problems.
Dave | | | | | Joined: Nov 2000 Posts: 582 Shop Shark | | Shop Shark Joined: Nov 2000 Posts: 582 | When I installed my dual Holley Webers, Tom Langdon told me that I did not need the insulators. Like Dave, no problems with just using the gaskets that came with the carbs. You adjust the choke by loosening the three or four screws on the ring around the choke element. Rotate the choke until it is lightly closed to the carb opening when cold. Then warm up your engine allowing the choke to open normally. You may have to do a slight readjust if it doewn't open completely. | | | | | Joined: Feb 2003 Posts: 218 Shop Shark | | Shop Shark Joined: Feb 2003 Posts: 218 | Ok, so I got the choke adjusted. Thanks for that. I'm havin gan issue going up hill when I try to accelerate, it feels like it is not getting fuel, but if I back off the pedal a bit, it will still climb and run, just under more load. I'm obviously not a carb expert, so I might need a little help here!
There are two jets on the top of the carb that are both marked 195, and two down in the fuel bowl that are marked 132. any ideas? | | | | | Joined: Sep 2007 Posts: 2,644 Shop Shark | | Shop Shark Joined: Sep 2007 Posts: 2,644 | Hesitation on acceleration usually means a defective accelerator pump. Did you rebuild the carb? | | | | | Joined: Feb 2003 Posts: 218 Shop Shark | | Shop Shark Joined: Feb 2003 Posts: 218 | I bought it from Tom Langdon. I think it was rebuilt prior to that. I'm going to try to adjust the float tonight and drill out the secondary jet to a 1/16" hole. I only had about a 1/4" of fuel in the bowl when I took it off, which doesn't sound like much.
Hopefully that will help. | | | | | Joined: Feb 2003 Posts: 218 Shop Shark | | Shop Shark Joined: Feb 2003 Posts: 218 | Just thought I would let everybody know, that on the advice of Tom Langdon I drilled out the secondary main jet to 1/16" and reset the float. Took the ol boy for a drive, and all is well. It idled and drove better than it ever has!!
Thanks for the help! | | |
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