Hello, I have some problem with the automatic choke of my 261 . It is really too automatic !because the valve closes itself when I touch the accelerator pedal with a cold or a hot engine. I tried many things. Isn't it better to buy a other carburator? Where can I find a Rochester single bore downdraft type BC?
I am also having a similar problem with my 58 and gas mileage is not good! On the open road running around 50-55MPH, I am only getting about 15MPG!!! Carb has been correctly rebuilt recently, float level checked several times, but I think it is the choke because after car has been sitting turned off for a few minutes and restarted, even when thoroughly warmed up, it seems to be running rich then after a minute or so smooths out! I have made many adjustments to the choke, but if I lean it off any more I will not have enough choke for cold starts! Anyone out there have some advice for this problem! There is a vacuum piston that is supposed to hold the choke in an open position! Do they ever need servicing? I have another carb, but it is off a 235 engine, might try to make one good carb from the two but really like to find a NOS BC Rochester Low Profile Carb, but doubt any are still around!
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1965 Thunderbird Special Landau 10th Anniversary Limited Edition only 4500 built 34,800 miles
The rochester one barrel BC was built from 1949 to 1967. Is it always the same model through all these years ? If I find a 1965, does it match for my '57?
62 AND BACK ,63 CHANGED TO A DIFFERENT CHOKE SYSTEM, SOUNDS LIKE YOUR NOT GETTING ANY HEAT UP TO THE CHOKE SPRING TO TURN IT OFF. TUBE PLUGED, VACUUM PORT PLUGED, PULL OFF PISTON INSIDE THE CHOKE UNIT SEIZED OR DIRTY AND TO TIGHT. CHOKE SPRING SET TO TIGHT ?? A VACUUM PORT INTO THE CHOKE HOUSING DRAWS WARM AIR FROM THE MANIFOLD UP THE TUBE AND ACROSS THE THERMOSTAT SPRING HEATING IT UP , CAUSING IT TO ROTATE AND OPEN THE CHOKE PLATE. NOT MUCH TO IT REALLY, THEY DO WORK !!!
In fact the carburetor on my '57 is a "auto-line C-90" ; it seems to be the same that a Rochester with the coil assembly on the center of the stat cover of the choke housing; I found two Rochester for sale and the coil assembly is on nine o'clock of the choke housing and the other at six o'clock. Is it a problem or can I buy it? 54 or 62 ? Here are some pictures of my car and of the carb for sale.
Hi, I can tell you the C-90 is just the remanufacturer's (Autoline) part number. You have a Rochester. I'm a little puzzled by your post, do you have two carbs availabe to you? If it was me, I'd grab 'em both, but I'm a carb junkie
it starts every time 
and I don't drive it in the winter.. Holley carb 4 speed
