Is it okay removing the black coating that’s on the backs and faces of the valves? I have done this and am not sure if I have damaged them by doing so, Have you had any issues?
Can you relap a used valve from a different head? Currently I'm running into an issue where I have lapped a brand new valve on a Volkswagen head and it seems that the more I lap it the more it leaks when I do a water leak down test. Any suggestions man?
Technically your not taking any material off while polishing a valve into a seat. My guess would be that you got unlucky with the used valve with too loose tolerances of the seat
I takes compound around the whole seat probably better didn't look like full coverage. I would have put it on my finger and definitely made it around the whole valve for sure thinner, Not to do a better job since it is kinda the valves your doing it on is not good if they didn't do a full circle for full coverage.
