Cars running rich. Put a complete rebuild kit on carb. Only has one idle mix screw. Seems pretty straight forward, but still cant get the carb set right. Any ideas?
It could be the idle screw, the float adjustment, or maybe the carb was not cleaned throughly but whatever it is we can only guessimate the problem because we do not have actual access to the problem.
vacuum leaks are also really common check around the intake with a little starting fluid, if the idle changes then you know you have a leak. I think the early rochesters also had some warping issues. what model is the carb (B, BC?)
im going to put my money in the trottle shaft. every b model ive built has the bowl to air horn warped but that just causes leaky rochester, but the shaft are natoriouse for hogging out. i have a guy that bushes them for me for like 30 dollars each. at first they dont idle right and you turn out the screw and then your exaust stinks. after you bush the shaft then the adjustment becomes more frendly. spray a little starter fluid on the shaft.
WHERE it is running rich would help diagnose the issue. If rich at idle; I would agree with Heathen that the float is the most likely culprit.....either incorrectly adjusted, or leaking. Another possibility which the original poster seemed to eliminate would be the idle mixture control screw. If rich at speed; then it could still be float issues, or the incorrect main metering jet, or the infamous model B warpage causing the power valve to always be open. If rich all of the time; then probably either float or too high pressure from the fuel pump. And it also easily be defective ignition. A perfect carburetor (description RARELY applying to a model B) would show rich if there is insufficient electrical energy to burn the fuel. Jon.
What are the specs? The manual says 1-3/4" when upside down. When right side up and hanging, what is that distance?
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