I made acouple of relies about overheating and noisy valve train. I totally forgot about the broken rocker arms and shafts. I broke several rocker arms and 2 rocker shaft. The shafts broke right at the rocker towers. What the problem was, was the valve stem keepers were in the wrong (lower) slot. Once in the proper(upper) slots the breakage stopped and the noise stopped. The head just had a valve job. It took ME several weeks to finnally find it.
