Take the fuel pump off and dig that bolt outta there!!!Or did you find it when you dropped the pan??One more thing to add for you and ratrodjake.If all else checks good you may have worn valvestem tips.They do mushroom over from time to time.A good valve job will entail the following:Grind/reface valves and seats/replace any valves or springs that are beyond servicable limits.Repair valve guides that are out of tolerance.Install new valve seals check spring/valve installed heights.Also replace any valve seats that are beyond serviceable limits.They will check /replace spring keepers and spring retainers as well if they are unserviceable.Depending on how much needs to be replaced/reworked a typical valve job on an I-6 head costs around 100.00 to 175.00.
Oh Heck yes I wouldn't have started it up again if I didn't find that bolt.. large chunks of metal and moving parts are not good combinations! are lifters usually replaced too?
No, lifters are usually left. A good mechanic might pull the one lifter and clean it and put it back in. If that doesn't fix the tapping he might recommend an oversize pushrod. The factory supplies them in several lengths. Usually .003" .005" and .010" longer than the stock length.
