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Old 03-17-2010, 08:22 PM
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dcdoug dcdoug is offline
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Cobra Make, Engine: CSX 6022, navy blue, period correct 427 SO
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Quote:
Originally Posted by FWB View Post
if you can verify the vacuum gauge is in correct working order, i would question the needle bouncing, how much is it bouncing, is it more than 1 in vac.your experiencing run on after the key is turned off. where is the timing set? is there fuel dripping into the plenum from the carb without moving the throttle? a fluctuation of 2 or more inches of vacuum can be a sign of valvetrain issues. broken springs or bad valve guides can cause a vacuum reading fluctuation. not trying to be an alarmist, and i have no idea how new or old your build is, but there seems to be more going on than having to adjust the carb.
Engine is about 8 months old and has 1,500 miles on it and was built by a professional who specializes in FEs and knows what he's doing. Checking the lash is on my list, but I would be surprised if there are any serious valve train issues. The needle bounces 1-2 inches of vacuum, mostly between 7-9".
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