My 87 B150 225 /6 failed inspections for, among other minor items I took care of the same day, "visible smoke."

I myself had seen no smoke. NJMVC does not make the distinction between blue and black smoke, and the inspectors did not tell me which it was.

It is easily inferrable that it was black, as the motor burns no oil (per plug evidence). I still have seen no smoke, but there is now some black stuff inside the tip of the tailpipe (new exhaust, headpipe back). (The plugs were sooty when I changed them, but I had put on 1,000 miles with the pigtail ripped off the choke T'stat, so I had just atributed it to that fact.)

I took it to a local shop authorized to reinspect so they could not see smoke either, and tell NJMVC that they had adjusted the carburator or something. I could not convince the guy who's shop it was of my idea.

His shop no longer works on carburated vehicles' fuel systems, but he was fairly certain all I needed was a rebuild and adjustment, and I'd legitimitely pass state inspection, no problem.

I had been putting off a rebuild as I'm entertaining swapping carbs when I get rid of the lean-burn stuff.

I bit the bullet, grabbed a kit. (I'm still not sure if I have Holley 1945 or 6145 as they take the same kit).

I started tearing down and cleaning the carb which I had bought "remanufactured" within the last 10 years. Not too long into it, I found that all the vent valve parts (except cover and cover screws) were missing.

Fortunately I never turned in the core of the original carb. I removed it's vent valve cover to see if maybe my specific application just doesn't use one (???), but all the parts for it were in the original one.

What kind of problems might this have been causing me, and what damage might this have done to other components/systems (evap canister, for instance) that I should look for?