Putting a old, used carb on and hoping for the best? If so, that's often good for an initial,leak until gaskets swell. This swelling may or may not stop leaking problems.. Other dried up parts may quickly fail, like a power valve in general use whether it suffers through backfires or not...
Rebuilding a Holley isn't hard. Float levels can be easily adjusted. Lean conditions , like too small a squirt from the accelerator pump (bad diaphragm, incorrect arm adjustment, cam on throttle main shaft, are not hard to fix. That leak on the back may only be a loose bowl screw. But you need to start with a carb in good condition, whether fresh off a running engine or properly rebuilt.
If you're comfortable with rebuilding a 4100, a Holley is more similar than something like a quadrajet.
1967 Galaxie 500 Red original Q code 428
1967 Galaxie 500 White with Black stripes 428PI clone- car is dead & long gone, sold near Oak Ridge TN 2000, would love to find it.....
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