harcos

Yeah the more I think about it the more I agree that at that particular point I have a lean condition, I picked up a new accelerator pump at NAPA and am going to change it out just because. My only vac advance checks were 1) does it hold vacuum? 2) does it change the idle/running when it is disconnected? 3) does it change the timing when I apply vacuum? It does all these things but I get your point I don't know how well it does it. It will be worth a second look if the acc pump doesn't fix it. I can see it squirt fuel right away when I push the plunger but it is a bit weak when I push it slowly that was good advice. as per the float this is a metal one that I upgraded when I rebuilt the carb. Thanks for the wisdom I will post results when I get a chance to change the pump.

Hey guys, I have to sell my moms car for her but first I need to get it running a little better. This is how it went. Her 1977 Buick Park Ave has always ran perfectly, I have kept up all the maintenance and about 5 years ago rebuilt the carb was one of the things I did. The car ran better than new for the next 3 years when she stopped driving it and parked it in her garage (not heated) . So she decides I should put it up as she cannot drive anymore so I took it out and put some seafoam in the fuel and drove a tank of fuel through it. I added some BG fuel system cleaner for the second tank. The car starts great, idles great and if you step on it it drives great. The problem is that it has a stumble if you give it a medium amount of throttle. Soft pedal is good, stomp on it and its good but a light to medium acceleration and it misses, pops and wheezes. I have taken the carb out and gave it a thorough cleaning and that helped some but I still have the issue. I have checked for vacuum leaks and cannot find any. I have double checked ignition timing and made sure my vacuum advance works correctly. Accelerator pump seems fine, I get a nice spray when I stroke the throttle. The needle valve and float are clean and seem ok. A mechanic I know suggested the float but it runs perfect through all but one condition so I am not sure if that could be it. I was certain that being parked for 2 years the problem would just be varnish from old fuel but its all been cleaned up. I have played with the air valves a little getting it a bit richer/leaner but the condition doesn't change. From my limited grease monkey experience I am leaning to a vacuum issue but as of yet I can't find a leak. Any suggestions would be much appreciated. Thanks 1977 Buick Park Ave 403 CID 4bbl Rochester