Isuzu 1999 RODEO Workshop Manual page 1143

6A–58 ENGINE MECHANICAL (6VD1 3.2L)
Valve Seat
1. Measure the protrusion of the valve stem when a new
valve is installed in the cylinder head. If the protrusion
of the valve stem exceeds the limit, replace the valve
seat insert or the cylinder head assembly.
Protrusion of valve stem
Intake
Standard: 39.32 mm (1.5480 in)
Limit: 39.47 mm (1.5539 in)
Exhaust
Standard: 39.3 mm (1.5472 in)
Limit: 39.45 mm (1.5531 in)
2. Measure the valve seat contact width. Make the
necessary corrections if the seat contact surface is
damaged or rough or if the contact width wear
exceeds the limit.
Valve seat contact width
Standard: 1.1 mm (0.0433 in)
Limit: 1.7 mm (0.0669 in)
Contact Surface Angle on Valve Seat on
Valve
1. Measure contact surface angle on valve seat.
2. If the measured value exceeds the limit, replace
valve, valve guide and valve seat as a set.
Valve contact surface angle: 45°
Valve Seat Insert Correction
1. Remove the carbon from the valve seat insert
surface.
2. Use a valve cutter to minimize scratches and other
rough areas. This will bring the contact width back to
014RW047
the standard value. Remove only the scratches and
rough areas. Do not cut away too much. Take care not
to cut away unblemished areas of the valve seat
surface.
Valve seat angle degree: 90°
014RS011
014RS012
014RW059