Valve lapping

bosstime2

Member
Do these look right after lapping?
 

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Those look okay for a hand lapping job. In the first picture, where we see your foot, the lapped area has a ring in t. I’d keep going until that ring is gone.

How are the valve seats? The valve is only 50% of the equation, the seats are the other 50%. The seat face needs to be just as clean as the valve face.
 
Shiny does not seal as well as the graying you have in your pictures, I found this out when I was working in an aircraft engine shop 50 years ago
 
Years ago when I had just bought my first Model A, an old timer (then because I was 15 years old) told me to lap the valves then mark the seat with a pencil lead. If the mark disappeared when you spin the valve, it was perfect.
Ed
 
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