Valve clearances

[White ls400]

Just a few questions on valve clearances. The main tell tale signs of valve clearances being out of spec would be clicking, ticking sound on idle? Would a pattering sound on higher revs also be a sign of this {kind of like heavy rain on a tin roof sound). Can the adjustment being out of spec be able to make faint knocking sounds throughout the rev range. As this has been mentioned as a possible cause for the sound thats like a pingin sound i have been hearing

 

[White ls400]

and roughly how long would it take a competent mechanic to adjust the valve shims

 

[-Nemesis-]

A ticking sound (loud) that always follows the revs is a bad valve tolerance. It's normally from the rear of the passenger side head. I just did mine which has been ticking for a few years, the culprit valve was 0.15mm out and it was enough to make it loud enough to hear over a 3" exhaust. It's now silent and i'm happy as a pig in ......

If you only do the passenger side it's not hard at all for a mechanic as there's no throttle body etc over that side.