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View Full Version : Valve Tap


OhioProstar
02-24-2005, 11:31 AM
So after more than 900 hours I think it is time to either replace the rockers, springs, lifters, and valve guides or take the heads in for a valve job. Here is some background info.

1) The valve train only taps when you run it up to WOT for more than a few minutes. It doesn't do it after I make runs at lower RPMs.
2) I attempted to adjust the valves late last summer and it seemed to work for 10-20 hours. I basically loosened the rockers until they made noise and then tighten them back until you couldn't hear the noise anymore and then added another 1/4 turn.
3) Since the engine I have ('95 350tbi) has flat valve tappets I think I can just buy new retainer nuts and then tighten to 20lbs, as the nuts may have been worn and backed out again after my first attempt to adjust.

Any thoughts?

Storm861triple
02-24-2005, 07:52 PM
How many valves are making noise?

-Tom

JimN
02-24-2005, 08:21 PM
Ohio- get a manual and adjust the valves according to their procedure. When you adjusted them, did you rotate the crank to the points on the cam where the rocker arms have the least pressure on them? If not, the added pressure from the cam lobes would give you a false reading if you used a torque wrench. On this motor, it's supposed to be done with a feeler gauge.