Overview
Practical, step-by-step procedures for setup, refacing, wheel dressing, and finish checks, so you can achieve consistent valve sealing results with confidence.
Recommended sequence
- Initial inspection and cleaning - Clean valves are a must before any grinding operation.
- Setup and runout checks - Verify your angle and valve rotation speed, set your valve stop, and add lube where needed.
- Refacing technique (angles, passes, finish) - Results vary depending on items, you may need to experiment a little to dial it in.
- Dressing the wheel - A critical operation to not only ensure the grinding surface is flat but also to open the grit of the stone.
- Final cleaning and verification - Wipe your valves clean and test in the head with bluing.
Apply the fundamentals as you go
Connect the "how" to the "why" for better results:
Concentricity and chucking basics:
Concentricity means that two round parts share the same center.
For engine valves, this means the valve face (the part that seals) and the valve seat (the ring it closes against) must line up perfectly around the same centerline.
If they aren’t concentric—if one is even a little off-center—the valve won’t seal tightly. That can cause leaks, loss of power, or engine damage. So, keeping perfect concentricity helps the engine run smoothly and efficiently.
see Fundamentals
Sealing geometry and face/seat angles:
The valve face and seat angles are like two matching cones that must fit together perfectly.
The valve face is the slanted edge around the valve, and the valve seat is the matching slant in the engine’s head. Most are cut at about 45 degrees, so when the valve closes, the two angled surfaces touch evenly all the way around.
This tight, even fit helps seal the combustion chamber, keeping the engine’s power and compression where it belongs—inside the cylinder!
see Fundamentals
Surface finish and verifying results:
Surface finish relates to how smooth or rough the valve face surface is after it’s been worked on.
When grinding or cutting a valve and seat, the surfaces should be very smooth so they seal tightly and don’t wear out fast.
Verifying results means checking your work — like using light, ink, or special tools to make sure the valve and seat touch evenly all the way around. If the surface looks shiny and smooth with a full ring of contact, you know you did it right!
- see Fundamentals
When problems appear
If you encounter chatter, taper, burn marks, or poor sealing:
A note on equipment
Consistent technique improves outcomes; a rigid chucking system and ergonomic controls can improve repeatability and throughput. Learn how the Kwik-Way SVSII Deluxe supports accurate refacing: Kwik-Way Accuracy
