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#1
05-18-2006, 11:29 AM
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1968 "400" running rich
I've recently installed a "400" in my 1966 GTO while awaiting the find of a proper 389. I've installed a set of rebuilt "trips" and find that the number 1,2 and 4 cylinders are running extremely rich. (spark plugs are burning black) while other cylinders seem to be OK. I replaced the spark plugs and checked the wires. The new spark plugs are now burning black again. The carbs have been rebuilt by a reputable mechanic that I have used many times before. Any ideas?
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#2
05-18-2006, 01:04 PM
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Have you checked the compression of all of the cylinders? My guess is that 1, 2, and 4 have lower compression. Another possibility could be the exhaust valve seats aren't seating properly.
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Junk is something you've kept for years and throw away three weeks before you need it! |
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#3
05-18-2006, 06:45 PM
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Are those 3 cylinders fed by the same side of the center carb? Could be that one side of the carb(s) is running rich, due to leaky jet or unevenly adjusted rod hangers, plugged airbleed, etc. If all the fouled cylinders feed off of the same plenum in the intake, excessive fuel in that side of manifold will be delivered to corresponding cylinders.
Or check other items as mentioned in other post.
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I could explain all this to the girl at the parts store, but she'd probably call the asylum. White '67 LeMans 407/TH350/Ford 3.89... RIP Red '67 LeMans. 407/TH400/Ford 3.25 |
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