[arkracing]

It's a normal occurance when you do valveseals that way.

I agree with the smacking the top of the valve with a hammer - just you can use a metal hammer - just don't go overboard. - plastic dead blow if you have it is best. Make sure you get a square hit so you don't chip the top of the valve or break it.
You'll hear it "Pop" as described - and should seal up - it you still hear "hissing" could be rings letting some into the crankcase.


"Lapping" the valves - basically you use a grit compund and spin the valve around in each of thier holes to clean up the valve and valve seat and give them a better seal.
its basically a "backyard rebuilding" technique