Latest post of the previous page:
This was a Boston Bob engine that we had to remove shims from under the rockers in waayyyyy back I can't remember when, because the valve adjusting screws were contacting the valve covers! It has an additional 7,000 miles, and has developed a sharp rapping click that comes up when warm. We diagnosed valve train, re-adjusted valves, timing, etc, and test drove on September 21st.sgkent wrote:check the rocker arm nuts to be sure they are torqued to factory spec. Don't tighten by feel. If a rocker arm stud nut is loosening that can cause it too. so can not being at TDC, or not feeling the lifter properly for zero lash. Colin will fix you up.
His conclusion at the end of our valve adjustment/timing adjustment was that the engine was quieter. My conclusion at the end of the visit was "engine is running acceptably, the sporadic clatter when warm sounds valve train-related and not serious IF:
it does not deteriorate.
Now I am getting reports that the noise is more serious-sounding, but I am not sure I have heard the alarming sound, I only got our post-valve adjustment sound where he said it was reduced.
I like SG Kent's suggestion to recheck the rocker stand support nut torque values (11mm nuts / 10 ft/lbs @ TDC only).
An immediate valve adjustment after doing the above is mandatory. Please check for any signs of contact between the valve cover and any valve adjusting screws. If you have to paint the insides of the covers to better see if contact occurs, do so.
Please keep me posted!