At work now, reading through all these, thought I'd answer a few responses. Thank you for all of those by the way. I am planning on working on the truck tonight with your responses. I had read numerous posts regarding a vacuum leak around the carb on here and other places. I have had someone ever so slightly holding the gas pedal down to keep the engine running and sprayed carb cleaner around the carb base (both with the Rochester and the Weber) and did not hear any variation in the engine speed. I also tried to spray a little around the intake manifold, and a couple other places I might have a leak and I didn't notice anything there either. If memory serves correct, the new Weber came with a new gasket to go on the manifold. I will again attempt to see if I can stabilize the idle and spray again, just to see if my installations were correct. It would be a mild surprise that I had a vacuum leak considering of how well it ran for a day, then degraded, unless the shop had somehow plugged a leak without knowing and it rattled loose. The spark plugs were black and sooty after only 40 miles or so. I figured it was running rough, so I cleaned them up and put them back in, ever so slightly better sounding, but overall, still rough. At this point, I should change out every vacuum hose on the engine. I should have done that in my initial work but will track down some hose and just replace everything for peace of mine. I do have a manual choke, and will check the cable adjustment on that when I get home.
@SimS, I'm not sure if sewing machine is the right way to word it, but for the times its been running well, it sounds like a smooth and quiet sewing machine. The rest of the time when it's running poorly it sounds rough. It ran fine when I picked it up, and apparently slowly degraded.
@Dragsix I will check Weber's settings and try and reset the carb to their suggested settings. I can say that it ran very well twice throughout the high altitude with no changes on my part, From the Friday afternoon I picked it up it was humming just fine, and by late Saturday afternoon the performance had diminished without messing with anything. I will buy some Champions, which ones should I use, resisted or non-resisted? I would like to get a known working spark plug. If nothing changes, I'll have at least eliminated that. I have checked vacuum advance and it is not ruptured. I did find a replacement, swap it in, and had no change. Both felt to give about the same resistance. I will check the clamp on the distributor, but I believe the carb advance is working. I will also check wire arrangement... in fact, I'll take a picture for all to see if that helps. The ballast is new and should be wired correctly but I will check that as well tool.
@glennstowing The shop mentioned a loose bolt on the starter and a couple other places I cant remember now. Starter is touchy, but works. (Floor type still)
