56 chevy 1 barrel carb problems

I have a 56 chevy 210 with a 235. I replaced the one barrel carb about two weeks ago. It has ran fine till yesterday. It backed fired while cranking and now it wont idle ( tried to adjust idle screw with no results) and will not pick up speed like normal. Any ideas on what it could be? Thank you.

 

This is one of those cases that the carb issue may be iginion related. You may have lost a tooth or 2 on the cam gear if it still has the OEM fiber one. Line the ball on the flywheel up with the pointer and rotor shoulld point to #1 or 6 wire. If things are OK there take a quick look at the points etc. What brand of carb ? Rochester or Carter? Carter does not have a power valve and Rochester has a metal spring and plunger system ,not much chance of a backfire causing a prob there. Is it running rich black smoke black plugs? If so carb most likely. Is the choke working OK? Still in all the carb is a likely suspect but check all of the above to rule out everything but the carb.

 

Also check that your vacuum advance mechanism is returning to normal, check point gap and timing as was suggested above.

 

Thanks guys. She is purring like a kitten again.

 

Well !!! Enlighten us !! What was the fix??