yanmar rocker arm oiling

[hoesz]

I have a 3tna72l-utbz yanmar in a mini excavator with excessive wear on the rocker arms and shaft. 50 lbs. of oil pressure at the block but basically no oil to the rocker arms. took the head off and no oil from the block oil port.Any suggestions Thanks, Larry

 

[kenmac]

Possibly the passages that lube this area are stopped up