valve adjustment

my 390 has a noisy lifter......can i remove the valve covers and adjust it while its running...or will oil fly all over the place ????  I remember that Chevy had these little oil clips that went on the rockers to deflect the oil...did not always work

the 1969 service manual shows adjustable valve train for 290-343-390 engines....picture shows studs....rocker arm rocker ball ??????   the book also says the 6 cylinder is non adjustable .....I have not removed the valve covers...however I went from a 10/40 oil to 20/50 and the noise began

Originally posted by william the 1969 service manual shows adjustable valve train for 290-343-390 engines....picture shows studs....rocker arm rocker ball ??????   the book also says the 6 cylinder is non adjustable .....I have not removed the valve covers...however I went from a 10/40 oil to 20/50 and the noise began

well, I think you found out why, you have to heavy an oil in the engine. go to 10-30 or 10-40  or even 15-40.   you need to look at the TSM closer,  dont go by the picture, "showing" means nothing.  read on how you set the valve train.  it will tell you to torque the nuts to 25lbs if I recall.   and forget about the chevy small block, dont compare the AMC V8 to the chevy, almost nothing is the same between the two.. I have fooled with both engines. I have a chevy truck too.

Yes there is a shoulder on the stud, and no set screw locking feature on the nut.  you can replace the stud to an aftermarket non shouldered stud and use a poly lock and make the rockers adjustable.  Most likely as others have said, the problem is wear in the valvetrain.  If its the rocker, which you probably know is a common problem on the chevy rocker and ball to the extent that replacement individual kits are commonly sold, then its an easy fix.

Originally posted by turbo Should be no problem making adjustment

How do you recommend adjusting past the shouldered stop in the stock valve train?