Cylinder Head Repair

Apply a light coat of Prussian blue (or white lead) to the valve face.

Lightly press the valve against the seat. Do not rotate the valve.

Check the valve face and seat for the following:

1. If blue appears 360° around the face, the valve is concentric. If not, replace the valve.
   

2. If blue appears 360° around the valve seat, the guide and face are concentric. If not, resurface the seat.
   

3. Check that the seat contact is in the middle of the valve face with the width below.
   

   Standard width:

   1.2 to 1.6 mm (0.047 to 0.063 in.)
   

If the seating is too high on the valve face, use 25 and 45° cutters to correct the seat.

If the seating is too low on the valve face, use 70 and 45° cutters to correct the seat.

Hand-lap the valve and valve seat with an abrasive compound.

After hand-lapping, clean the valve and valve seat.

Apply a light coat of Prussian blue (or white lead) to the valve face.

Lightly press the valve against the seat. Do not rotate the valve.

Check the valve face and seat for the following:

1. If blue appears 360° around the face, the valve is concentric. If not, replace the valve.
   

2. If blue appears 360° around the valve seat, the guide and face are concentric. If not, resurface the seat.
   

3. Check that the seat contact is in the middle of the valve face with the width below.
   

   Standard width:

   1.6 to 2.0 mm (0.063 to 0.079 in.)
   

If the seating is too high on the valve face, use 25 and 45° cutters to correct the seat.

If the seating is too low on the valve face, use 75 and 45° cutters to correct the seat.

Hand-lap the valve and valve seat with an abrasive compound.

After hand-lapping, clean the valve and valve seat.