[18436572]

I recently picked up a 68 tempest with a non-original late 60's 350. There is considerable valve noise on the drivers side. I removed the cover and found 1 out of all the rocker nuts a little loose. I tightened it down like the others. Didn't seem to help much. From what I have read, I must have the "net lash" system. Can anyone recommend the next steps to solving the noise problem?

 

[LATECH]

Could be the rocker arm and pivot ball is worn out. Also press in studs can pull out creating excessive lash and a tick or tap. Lack of oiling due to sludge,plugged pushrod holes and excess clearance in bearings (worn engine) can all cause lack of oiling.
Being the drivers side oils before the passenger side, chances are the rocker stud may have pulled out .