Valve Rocker Arm and Push Rods Cleaning and Inspection

Important:  Parts that are to be reused must remain sorted or organized in order to return them to their original location.

1. Clean the components with cleaning solvent.
   CAUTION: Refer to SAFETY GLASSES CAUTION in Cautions and Notices.
2. Dry the components with compressed air.
3. Inspect the valve rocker arms for wear or scoring in the ball area.
4. Inspect the valve rocker arm push rod sockets and valve stem tip mating surfaces.
5. Inspect the valve rocker arm ball for wear or scoring.

   These surfaces should be smooth with no scoring or exceptional wear.

   Fig 1: Valve Rocker Arms & Nuts

   Courtesy of GENERAL MOTORS CORP.
6. Inspect the push rods (1, 2) for worn or scored ends.

   These surfaces should be smooth with no scoring or exceptional wear.

7. Inspect the push rods for bends. Roll the push rods on a flat surface to determine if the push rod is bent. If it rolls smoothly, it is OK. If the push rod does not roll smoothly, replace the push rod.
8. Inspect the push rod oil passages for restrictions.
   • Clean out the push rod tube with compressed air.
   • Inspect by looking through the push rod tube for obstructions. A clear push rod will allow light through.
   • Replace push rod(s) that cannot be cleaned out.
   Fig 2: Pushrods

   Courtesy of GENERAL MOTORS CORP.

   Important:  A light contact mark on the rocker arm stud is normal. A noticeable groove in the rocker arm stud is excessive wear and the rocker arm stud should be replaced.

9. Inspect the rocker arm studs for the following conditions:
   • Damaged threads (1)
   • Excessive wear or damage made from contact between the rocker arm and rocker arm stud (2)
10. Valve rocker arm studs with excessive wear and/or damage must be replaced.
    Fig 3: Inspecting Rocker Arm Studs

    Courtesy of GENERAL MOTORS CORP.
11. Inspect the push rod guides for the following conditions:
    • Wear between the push rod and the push rod guide (1)
    • Bent push rod guide (2)
    • Cracks
12. Push rod guides with excessive wear and/or damage must be replaced.
    Fig 4: Inspecting Pushrod Guides

    Courtesy of GENERAL MOTORS CORP.