GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2007 🢒 Wave 🢒 Engine 🢒 Engine Mechanical - 1.4L SOHC 🢒 Valve Guide Reaming, and Valve and Seat Grinding

Tools Required

    • KM-419 Distance Gage
    • KM-571-B Gage or Equivalent
    • KM-340-1-C Cutter Set (Including tools KM 340-7, KM 340-13, and KM 340-26)
    • KM-253 Valve Guide Reamer
    • KM-254 Valve Guide Reamer
    • KM-255 Valve Guide Reamer

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1241769 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

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1241775 Size: SH
  1. Ensure that 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 angle is 46 degrees.

    4. Object Number: 1241778 Size: SH
  4. Check the valve stem projection using the KM-419  (1) .

Valve Guide Ream

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1241779 Size: SH
  1. Measure the diameter of the valve guide using the KM-571-B and a commercially available inside micrometer.

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

  2. An oversize code is on the valve guide and the valve stem end. The Valve Guide Reaming Table gives the correct size, reamer, and production code for each service code. Refer to Engine Mechanical Specifications .
  3. Ream the valve guide from the upper side of the cylinder head to the next oversize. After reaming, cross out the code and emboss the valve guide with the new code.

Valve Seat -- Cut

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1241780 Size: SH
  1. Place the cylinder head on wooden blocks.
  2. Cut the intake and the exhaust valve seats using the KM 340-7 as follows:
    3. • Valve seat--A 45 degree side (b) using the KM 340-13
    • Upper correction angle--A 30 degree side (a) using the KM 340-13
    • Lower correction angle--A 60 degree side (c) using the KM 340-26

    Object Number: 1241778 Size: SH
  3. Clean the chippings from the cylinder head.
  4. Inspect the dimension for the proper valve seat width.

    5. Specification

        • Intake--1.3-1.5 mm (0.051-0.059 in)
        • Exhaust--1.6-1.8 mm (0.063-0.071 in)
  5. Inspect the valve stem projection using the KM-419  (1).

    6. Object Number: 1241782 Size: SH
  6. If the dimension is exceeded, install new valves and then check the valve stem projection again. Refer to Valve Guide Reaming, and Valve and Seat Grinding .
  7. If the valve stem projection is still too large despite replacing the valves, replace the cylinder head.