The Stovebolt Site Forums The Shop Area Engine Shop Rochester B Choke Bowl/Choke Valve Housing Gasket Holes

Joe, I see that my Roch B's fuel inlet does, indeed, receive a flared fuel line. The previous owner, however, did not use any flare fitting on the line he put into it. I shouldn't be surprised: he also used an incorrect gasket between the airhorn and float bowl (covering a passageway) and he also used an incorrect gasket between the float bowl and the throttle body (covering the pressure release slots on the bottom of the float bowl.) I even have to wonder whether my float bowl is, itself, correct for my airhorn because I have not come upon any published information indicating that Rochester used these vented float bowls on the '66 C10 250 Powerglide. Interestingly, I note upon close inspection that my throttle body's flange casting does not perfectly match my float bowl casting. The mating surfaces each have very slightly different mating gasket beads. Almost imperceptible. Since my carb's tag is missing, and none of the stamped numbers anywhere on my carb suggest a particular model number, I suppose I will not ever know for certain. I know that Rochester had numerous variations of the 'B' for various vehicle models, but I did not know that they varied the carbs within the same vehicle model. That is, I figured all '66 C10 250 Powerglides would have one particular version of the Roch B (7026011 w/idle vent adjustment screw on top of airhorn, per the manual). But I have heard from others with my truck that their Roch B lacks the float bowl slots. So either Chevy put in a version of the carb not acknowledged in the manual or my previous owner has mixed & matched carb sections. Once I get my carb back on the engine, now with its correct gaskets, I hope to be able to "feel" whether my engine is happy with my carb. Fortunately, in the eight months or so that I have my truck, I did not experience any idle or hot-starting issues, nor leaking. I did have poor mpg, but I do not have the level of carburetor knowledge to know whether blocking the slots would cause that. You know, 'they say' that the Roch B is a simple carb to work on. Maybe it is. But that simplicity is well off-set by the tedious task of identifying which simple Roch B one actually has -and what, if anything, a previous owner has done with it.