Burnt Rocker Balls

[Grumpy]

Guys,
I have a 327 SBC that was professionally built about 15 years ago. Motor is mildly modified 350 HP out of my 1966 Corvette. Cam is a Comp Cam roller hydraulic with less than .500 lift. Rockers are Comp roller tip. Oil pump is a Melling 55 psi, oil pressure with 10W-30 hot is 58 psi. Motor has about 25K trouble free miles on it.
Two months ago I changed oil/filter at 2K miles as usual. Oil used is a well known Pennsylvania base oil. Two weeks later I have noise and blackened rockers with carbonized oil around the pivot ball on right side of motor. With motor idling (30 psi) there is a good supply of oil to all rockers.
My first thought was a blockage in the lifter feed galley, but ALL rockers are oiling fine. Replaced rockers, lubed with break-in lube and drove about 200 miles. Same thing is happening again, black rockers on both banks this time.
What is your best idea for the cause of this? Could is be the low amount of ZDDP in the oil I am using? Any advise apricated! Thanks Bill

because the issue started with the oil and filter change Id strongly suggest,
that you take the effort too, verify the dip stick reads correctly,
if the oil levels low its a problem, change both the oil filter and the oil being used,
do it immediately before more damage, potentially occurs.
personally Id pull all the rockers and pushrods and soak them in gas/50% and diesel 50% mix,
and carefully clean the interior of the pushrods and blow them out with high pressure air,
and coat all the parts with 30% moly assembly lube /70% MMO, oil before re-assembly
a WIX filter and VALVOLINE 10w 30 would be a decent choice
whats your oil temperature? it should be lower than about 210f-220f max most of the time
your rocker geometry may be restricting the volume of oil flowing over the rocker ball pivot.
Id also suggest you back off the rocker adjustment nut at idle until the rocker clicks,
then very slowly tighten the rocker adjustment nut just until the clicking stops,
then add only 1/4 turn of preload as that will maximize oil flow to the rockers.
adding a quart of MMO,

and ZDDP certainly would not hurt but thats optional, as good oil should be all thats required

http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.com/index.php?threads/correctly-adjusting-valves.196/

http://garage.grumpysperformance.com/index.php?threads/rocker-push-rod-wear-issues.9815/

http://garage.grumpysperformance.co...il-choices-for-cam-break-in.13602/#post-70236

http://garage.grumpysperformance.com/index.php?threads/cam-wear-articles-you-need-to-read.282/