Distributor Knock ?
This is an ongoing nagging issue. I can feel a knock around the #4 and #3 post and the vacuum canister on the HEI cap. I have done a search on this read many posts and with all of their successes they didn't work for me.
What I have done ( before I found noise in cap ) so far is:
Replaced a good timing chain, found rubbing on inside of cover - no fix.
Multiple valve adjustments.
Modified valve cover breather baffle.
Good operation of water pump, fuel pump and rod; fan and assembly.
After I discovered knock in cap I:
Minimized shaft endplay to .0023".
Checked pole and assembly for centering.
No side play in shaft
Rotor and cap show no markings, yes thay are mounted properly.
Cap contacts firm
Gear has normal polished wear but not gouged.
Any else I need to check before I go to a new GM piece?