Valve Seats

GENERAL INFORMATION

Installing the pilot on the grinding tool

1. PILOT

Valve seat grinding stone

Valve seat face angles

1. INTAKE VALVE SEAT.

2. EXHAUST VALVE SEAT

Valve lapping

PROCEDURE.

1. Insert the pilot into the guide bushing.

2. Install the grinding stone with the 45° cone side onto the valve seat, see illustration. Valve seat grinding stone.

3. Attach the handle with the spacer sleeve. Continue grinding until the grinding stone begins to remove metal from the seat evenly around the entire

circumference. Remove as little metal as possible from the seat face.

4. Turn the grinding stone over and install it with the 30° cone side onto the

seat. Grind the seat face in the same way. The same grinding stone is used for intake and exhaust valve seats.

5. Coat the seat face with fine lapping compound, insert the valve into the guide and carefully rotate it with light pressure. Lift the valve and check

the contact of the valve face with the seat. If the valve does not contact the seat evenly, repeat the seat grinding operation.

6. Valve lapping.

After grinding, which must ensure valve seat sealing, the valves are normally lapped to the seats. For finishing the seats,

use only fine lapping compound. For even distribution of

compound around the seat circumference, periodically lift the valve off the

seat during lapping. After lapping, clean the valve face and seat of lapping compound residue.

Before installing the valves, lubricate their stems.