Ok, It turns out my car does not have the pointer on the front cover, so checking the timing is kind of difficult. The car runs for about .3-1 second after I turn the key off, (of course its stumbling then dies). My plugs still look a bit lean. My question is could this be because the timing to too advanced? also, without checking the fuel pressure, what are symptoms of a dying fuel pump? considering I have an 800cfm carb, I expected the car would tend to be richer than leaner... however all adjustments have still been showing the lean side of the car. Thanks, Kevin Oh, im sort of in a hurry since i am scheduled to race a friend tonite... (im probably going to lose...)
A combination of too high an idle speed and lean fuel mixture will cause run on. I remember my 72 Skylark had an idle stop solenoid that allowed a higher idle speed, but let the throttle plates close when you shut the ignition.
Do you have an electric fan??? I had one do that once [ in my 79 Duster] when I had it hooked up keyed I think. Anyways, the car would still run as the fan spun down. Matt uzzled:
That will do it too. I yanked mine when I rebuilt the carb and if I am out hot roddin it, mine will do that sometimes when I shut it off. I assume? Mine is from the higher than normal idle / plate position and when its warm that extra fuel can pop off for a sec. Matt uzzled:
Thanks for the help... I lowered the idle a bit and she is still doing it.. hmmmm.... im still wondering why my car is constantly showing a lean condition..... Kevin
You could have a vacuum leak, which would cause a lean condition, and a possible run on situation. Built up carbon on the piston tops and Combustion Chambers WILL cause run on as well. You have an 800 CFM Q jet?? If you have headers and / or a free flowing dual exhaust, that can cause a lean condition. I know this from experience. Even with a 750 CFM Holley Double Pumper, which is a fairly richly calibrated carb, I had Very White plugs. I ended going up 2 sizes on the primary jets, which helped.
SBBuick, I looked for a vac leak but found none. Yeah, I have a 800 CFM carb that was rebuilt to stock specs for a 69 430ci motor, I stuck the 750s secondry metering rods and hanger and that helped to make the car run better (not bog) but there is still some work to be done... The exhaust is a flowmaster system connected to a set of TA headers... the intake is a Ta Manifold as well.... and an open element filter on top... (classic no frills chrome). Other than that the car is stock.
