The vacuum advance should not affect a cold start at all. Those backfires could have damaged or collapsed a float if you've got the usual float made of thin brass. It wouldn't hurt to open the carb up and check the float level, etc.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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