Valve and Seat Grinding
WARNING: This page is about a different car, the 2019 GMC Savana 3500, 2019 GMC Savana 2500, 2019 Chevrolet Express 3500, and 2019 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.
Remove the carbon from the valve guide and valve seat surface.
- Resurface the valve face to 45 degrees. If valve margin falls below specifications after resurfacing then discard valve.
- Use a suitable tool to bring the valve contact width to the standard value. The valve seat angle is 45 degrees.
Apply valve lapping compound to the valve seat surface.
- Insert the valve into the cylinder head.
- Turn the valve back and forth in its seat to lap the valve face to the valve seat.