How To: Lapping Your Valves At Home
I learned to do it about 30-40 years ago. I was taught that it required a back and forth motion, with a gradual advancement. Why? TBH, I really have no idea! I'v been using this too for decades, and I really don't know why.
Is it better than a drill? No, I don't think so. Your way with a drill works just as well and is a lot faster.
I asked a pro builder one day if it was worth hand lapping valves. He told me it probably wasn't worth the effort for most new engines. But I do it anyway. If you get a nice even honing band on valve face and seat, you get visual confirmation that they're square to each other.
Is it better than a drill? No, I don't think so. Your way with a drill works just as well and is a lot faster.
I asked a pro builder one day if it was worth hand lapping valves. He told me it probably wasn't worth the effort for most new engines. But I do it anyway. If you get a nice even honing band on valve face and seat, you get visual confirmation that they're square to each other.
Thanks for posting this. Atv and dirt bike guys do this on refreshes. This is the first I've seen somebody do it on a car valve. Any tips on keeping the valve square to the seat? Or is it just "feel"?
