Operation CHARM: Car repair manuals for everyone.

Valve Seat

VALVE SEAT
1. If necessary, resurface the valve seat by using a 45° valve seat cutter and/or resurface the valve face.
2. Apply a thin coat of prussian blue to the valve face.
3. Check the valve seating by pressing the valve against the seat.
If blue does not appear 360° around the valve seat, resurface the seat.





4. Measure the seat contact width.

Width: 0.8-1.4 mm (0.032-0.055 in)





5. Verify that the valve seating position is at the center of the valve face.
1) If the seating position is too high, correct the valve seat using a 70° cutter, and a 45° cutter.
2) If the seating position is too low, correct the valve seat using a 35° (IN) or 30° (EX) cutter, and a 45° cutter.
6. Seat the valve to the valve seat using lapping compound.
7. Check the sinking of the valve seat.
1) Measure the protruding length (dimension L) of the valve stem.





Dimension L: 33.6 mm (1.323 in)

2) If L is as below, it can be used as it is.

33.6-34.1 mm (1.323-1.342 in)

3) If L is more than below, replace the cylinder head.

34.2 mm (1.346 in)