Vauxhall Workshop Service and Repair Manuals

Valve Seat Rings, Cut

Remove combustion deposits from valve seat ring.

Insert Guide Pin KM - 340 - 7 as far as stop into valve guide and tension it.

Set Valve Cutter KM - 340 - 12 (234) for exhaust valve or KM - 340 - 11 (230) with 45 degree plane surface (note arrow on cutter) on valve seat ring.

Mount handle with joining piece and begin cutting, removing as little material as possible from valve seat.

Cutting should be from top to bottom using very little pressure, so that the seat remains concentric to the valve guide.

Then correct top and bottom with 75 degree Cutter KM - 340 - 14 (206) and 15 degree Cutter KM - 340 - 25.

Observe width of valve seat.

Coat valve seats with finishing paste and insert valve in guide. With slight pressure rotate valve 1/6 of a turn with feeling. Lift up valve and check contact pattern. If valve does not make complete contact, regrind seat lightly once again.

Prescribed valve seat contact width

new valve seat rings:                  1.2 - 1.5 mm/

                                               0.005 - 0.006 in.

used valve seat rings max.:                 2.0 mm/

                                                           0.008 in.

Check valve recess.

See operation "Cylinder Head, Disassemble and Reassemble".

If the maximum values are exceeded and regrinding of the cylinder head gasket surface no longer possible, the cylinder head can no longer be used.

The valve end must not be reground.