Valve Margin Measurement Procedure; Valve-To-Seat Concentricity Measurement Procedure - Suzuki XL7 2007 Service Manual

1D-184 Engine Mechanical:

Valve Margin Measurement Procedure

1. Measure the valve margin using an appropriate
scale.
2. Reference the specifications in this section for
minimum valve margin and compare them to your
measurements.
3. If the valve margins are beyond specification,
replace the valves.
4. If the valve margins are within specification and do
not require refacing, test the valve for seat
concentricity using the Valve-to-Seat Concentricity
Measurement Procedure.
Valve-to-Seat Concentricity Measurement
Procedure
NOTE
• Checking the valve-to-seat concentricity
determines whether the valve and seat are
sealing properly.
• You must measure the valve face and the
valve seat to ensure proper valve sealing.
1. Coat the valve face lightly with blue dye (3).
2. Install the valve in the cylinder head.
3. Turn the valve against the seat with enough pressure
to wear off the dye.
4. Remove the valve from the cylinder head.
5. Inspect the valve face.
– If the valve face is concentric, providing a proper
seal, with the valve stem, a continuous mark will
be made around the entire face (1).
NOTE
The wear mark MUST be at least 0.5 mm
(0.020 in) from the outer diameter, the margin,
of the valve. If the wear mark is too close to
the margin, the seat must be reconditioned to
move the contact area away from the margin.
– If the face is not concentric with the stem, the
mark will NOT be continuous around the valve
face. The valve should be refaced or replaced and
the seat must be reconditioned using the Valve
and Seat Reconditioning Procedure.