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TR2/3/3A Valve Knock Question

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Here is a photo. The wear is there - especially if there is supposed to be brass. But I was looking for divots that would cause .006" of difference. The pitting in #8 looks worse than it is. But is still not very deep.
IMG_0476.jpg

you say you the settings were reduced to .03. That's a much wider gap? I could reduce engine "knock" by tightening it. Probably to nearly zero clearance. I'm thinking of doing my test again and recording it this time to see if anyone might have some input as to what is going on.
 
I’m with Steve. 3 years ago I bought a lot of 7 rocker shafts off Craig’s. list. All those arms and all those shafts I got one usable rocker set up...and I had to dress the tips on the arms I used. I would expect significant wear on any shaft assembly with 50k miles or more. I can’t tell from the pics, but it sure appears that those tips are worn. They start perfectly smooth and rounded.
 
Thanks John. Do you have any input about setting the clearance on the rockers? Why I can get the knock to go away with it tightened? How little cleanance can I get away with?
 
I will try and measure. I don't have a dial indicator, so I'll have to borrow one.
 
I am probably not clear plus my math was wrong. What I am talking about is when an engine has a loud rocker/lifter people will cheat and tighten that one loud lifter up from .010 to .005 ---those old VW engines were set I think at .006 on their solid lifters and were still noisy. Old engines with solid lifters can make a lot of noise. In addition, I am talking about the shaft the rockers roll on—the bottom of the shaft itself is usually cut on an old engine at least .010—the round brass bushing is inside the rocker and rolls on the shaft and when that is gone the shaft gets cut badly.

Cheating on the specification and tightening from .010 to .005 or even .003 is not advisable, but I would go down to .005 on an old engine on one or two, but I am a hillbilly.

Keep at it you will find the answer because you do not quit, right on!!!

Push one of the rockers side to side into the spring to expose the shaft under the rocker.
 
If you’ve never seen a worn shaft, you would likely miss it. The spring tension on the shaft takes up the play, so makes it seem tight. Your first time you would have to disassemble the shaft to see the wear. After that, you will know where to look.
 
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