new carb issue - i think Options

[william1764]

Finally corrected the serious backfire issue i had (IMG:style_emoticons/default/cheer.gif) exhaust leak was found (crack at header mount flange area) and repaired...long story but excessive/loud backfire on decel has been FINALLY eliminated. Overnight however i developed a sputtering/popping thru carbs. Uneven and rough acceleration up thru 3k RPM and higher. idle is irregular but constant - either a little high or a little low but steady...varies on the day. I have noticed since the carbs were rebuilt last september fuel mixture out of the exhaust at startup...i assume too rich? new plugs already dark. i've only put on a couple hundered miles since carb rebuild so not much experiance since rebuild.

what could happen to cause the engine/carbs to take such a drastic turn from one day to the next with touching them? Could this be valve issue?

for those not familar with past issues my set up is 74 2.0 with weber dual IDF 40's.

on another note, anyone in balt/dc going to hershey?

[jmill]

I'd check the idle jets first as already mentioned. Check pump jets for even spray. A stuck pump jet check valve will cause lean pops and poor acceleration. A linkage out of adjustment will also cause similar issues.