GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 Optra - Mexico 🢒 Engine 🢒 Engine Mechanical - 1.4L (L95) 🢒 Valve Guide Reaming, and Valve and Seat Grinding

Tools Required

    • KM-571-B Gage or equivalent
    • KM-805 Valve Guide Reamer
    • KM-340-1-C Cutter Set

Valve Grind-In

    Object Number: 1372422 Size: SH
  1. Lubricate the valve stem using a fine-grained paste.
  2. Lift the valve rhythmically from the seat with a commercially available valve grinding tool in order to distribute the paste.

    3. Object Number: 1241773 Size: SH
  3. Check the contact pattern on the valve head and in the cylinder head.
  4. Clean the valves, the valve guides, and the cylinder head.

Valve Grind

    Object Number: 1241775 Size: SH
  1. Ensure there are no crater line burns on the valve cone.
  2. The valve may be reground only 2 times. Do not grind the valve stem end.
  3. The angle at the valve face is 45 degrees.
  4. Inspect the assembly height of the intake valves and the exhaust valves.

Valve Guide - Ream

    Object Number: 1372423 Size: SH
  1. Measure the diameter of the valve guide using the KM-571-B  (1) and a commercially available inside micrometer.

    2. Object Number: 1372424 Size: SH

    Important: Valve oversizes may already have been fitted in production.

  2. An oversize service code is on the valve guide and the valve stem end. The Valve Guide Reaming Table give the correct size, reamer, and production codes for each service. Refer to the Valve Guide Reaming Table in Engine Mechanical Specifications .
  3. Ream the valve guide from the upper side of the cylinder head to the next oversize using the KM-805  (1).
  4. After reaming, cross out the code and emboss the valve guide with the new code.

Valve Seat - Cut

    Object Number: 1241780 Size: SH
  1. Place the cylinder head on wooden blocks.
  2. Cut the intake and exhaust valve seats using the KM-340-7 included in the KM-340-1-C as follows:
    3. • Valve seat: A 45-degree side (b) using the KM-340-13 included in the KM-340-1-C
    • Upper correction angle: A 30-degree side (a) using the KM-340-13 included in the KM-340-1-C
    • Lower correction angle: A 60-degree side (c) using the KM-340-26 included in the KM-340-1-C
  3. Clean the chippings from the cylinder head.
  4. Inspect the dimensions to make sure the valve seat width is as follows:
    5. • Intake: 1.17-1.57 mm (0.046-0.062 in)
    • Exhaust: 1.07-1.47 mm (0.042-0.058 in)
  5. Inspect the assembly height of the intake valves and the exhaust valves.
  6. If the dimension is exceeded, install new valves.
  7. Inspect the assembly height of the intake valves and the exhaust valves again.
  8. If the valve assembly height is still too large despite replacing the valves, replace the cylinder head.