metal rattle goin on from head

Ya, my thoughts are pull the covers and run the overhead ASAP. If your hearing something that was not there before then something has happened. Have a good look around and do a good set, chances are it might be just a loose valve.

 

Check for Broken Spring.

 

Is it constant might be an air compressor see if it goes away when the air dryer purges and the compressor quits pumping.what engine do you have?i know isx makes lots of noise if the scissor gears are not set up right and cat has issues with rocker arm bolts,

 

mine made a heck of a noise kinda like yours when they did the head last time ideler gear below the cam gear was way tight i first thought the compressor was bad

 

Any Updates bull hauler ?

 

Since you didn't identify which engine I would look first at valve adjustment. I have had valve adjustments in the past that were very hard to adjust because of bridge issues. You may use a stethoscope on the rocker shaft to identify the culprit without having to do a full adjustment. You may also try to slip a feeler gage between rocker and valve bridge while engine is running to isolate the cylinder. Be careful if it is too tight it will mess up the feeler gage. If it is loose it will quiet the noise down. Depending on engine 63K is a good time to do a valve adjustment on anyways especially with a new head.