GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 41478 Crankshaft Front Oil Seal Installer
    • J 41665 Crankshaft Balancer and Sprocket Installer
    • J 42386-A Flywheel Holding Tool
    • J 45059 Angle Meter

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1559840  Size: SH

    Important: 

       •  For manual transmission applications, note the position of the crankshaft balancer before removal. The balancer does not use a key or keyway for positioning. Mark or scribe the end of the crankshaft and the balancer before removal. The crankshaft balancer must be installed to the original position. If replacing the crankshaft balancer, note the location of any existing balance weights, if applicable. Install new balance weights into the new crankshaft balancer, if applicable. Crankshaft balance weights must be installed into the new balancer in the same location as the old balancer. A properly installed balance weight will be either flush or below flush with the face of the balancer.
       • The crankshaft balancer installation and bolt tightening involves a 4 stage tightening process. The first pass ensures that the balancer is installed completely onto the crankshaft. The second, third and fourth passes tighten the NEW bolt to the proper torque.
       • The used crankshaft balancer bolt is used only during the first pass of the balancer installation procedure. Install a NEW crankshaft balancer bolt and tighten as described in the second, third and fourth passes of the balancer bolt tightening procedure.

  1. Install the J 42386-A and bolts.
  2. Use 1 M10 - 1.5 x 120 mm and 1 M10 - 1.5 x 45 mm bolt for proper tool operation.

    Tighten
    Tighten the J 42386-A bolts to 50 N·m (37 lb ft).


    Object Number: 63153  Size: SH
  3. Using the old balancer as a reference, mark or scribe the new balancer in the same location, if applicable.
  4. Install balance weights into the new balancer, if applicable. Refer to Engine Balancing and Crankshaft Balancer Cleaning and Inspection .

  5. Object Number: 1759519  Size: SH
  6. Install the crankshaft balancer washer (1) onto the crankshaft balancer.

  7. Object Number: 1764786  Size: SH

    Important: The balancer should be positioned onto the end of the crankshaft as straight as possible prior to tool installation.

  8. Position the balancer (1) onto the end of the crankshaft.

  9. Object Number: 1408878  Size: SH
  10. Use the J 41665 and the J 41478 in order to install the balancer.
  11. 6.1. Assemble the J 41478 threaded rod, nut, washer, and the J 41665 installer.

    Insert the smaller end of the installer into the front of the balancer.

    6.2. Use a wrench and hold the hex end of the threaded rod.
    6.3. Use a second wrench and rotate the installation tool nut clockwise until the balancer is started onto the crankshaft.
    6.4. Remove the tool and reverse the installation tool.

    Position the larger end of the installer against the front of the balancer.

    6.5. Use a wrench and hold the hex end of the threaded rod.
    6.6. Use a second wrench and rotate the installation tool nut clockwise until the balancer is installed onto the crankshaft.
    6.7. Remove the balancer installation tools.

    Object Number: 1408847  Size: SH
  12. Install the used crankshaft balancer bolt (139).
  13. Tighten
    Tighten the crankshaft balancer bolt to 330 N·m (240 lb ft).

  14. Remove the used crankshaft balancer bolt.

  15. Object Number: 63245  Size: SH

    Important: The nose of the crankshaft should be recessed 2.4-4.48 mm (0.094-0.176 in) into the balancer bore.

  16. Measure for a correctly installed balancer.
  17. If the balancer is not installed to the proper dimensions, install the J 41665 and repeat the installation procedure.


    Object Number: 1408847  Size: SH
  18. Install the NEW crankshaft balancer bolt (139).
  19. Tighten

    1. Tighten the crankshaft balancer bolt a first pass to 50 N·m (37 lb ft).
    2. Tighten the crankshaft balancer bolt a second pass to 140 degrees using the J 45059 .
  20. Remove the J 42386-A .