I put a k&n filter onto my weber 32/36 and now blue smoke comes out at idle. I didn't route the crankcase vent back into the carb like the old one had it, I just left it free. Do I need to adjust my carb to make up for the non exsitant oil from before? It doesn't appear to release much at all through there anyways. I had a rebuild about 2000 miles ago could it be the rings haven't seated yet, spark plug #4 is pretty black even after highway driving. Any ideas, thanks in advance.