I had a chance to get back to this and try some more diagnosis. All the pushrods are turning, none seem to be bent. All the rocker studs are the same height. By sight anyway, I didn’t use a straightedge. With my stethoscope I was able to narrow the noise down to #6. It seemed like exhaust was louder than intake but I’m not sure. I adjusted the valves on #6 and now the tapping is almost imperceptible at idle. But at 1500 RPM or so its definitely still there. I’m thinking of getting a couple of lifters (~$8) from O’Reilly and replacing the ones at #6. What do you guys think? Is it most likely a waste? Is there any danger of making the problem worse by damaging the cam?
Thanks for any comments.
Leon
