Hi

I just finished the head gasket replacement, and a valve job since I am in there. The engine runs fine for about 30 minutes and then suddenly developed this valve tick.

Possible cause is somehow an old piece of silicon gunk ended up in an oil passage and causing a valve lifter to make that noise.

Question 1: should I just drive it a few weeks to see if it passes like a piece of Lego in a kid?

Question 2: Should I bite the bullet, pull the cam shafts and inspect the lifters? What are the signs of a bad lifter?

I should add that this is my sister's car and she let hack mechanics work on it for a long time. I found all kinds of silicon junk outside and inside the engine.

thank for any insight.