Removal & Installation
The following procedure requires the use of a torsional damper puller/installer tool such as GM tool no. J-23523-F or an equivalent.
DO NOT attempt to remove the damper using a jawed puller or the hub may be destroyed. The internal weight section of the balancer is assembled to the hub using a rubber-type material. The proper puller type tool is needed to prevent damage.
- Disconnect the negative battery cable for safety.
- Remove the engine cooling fan, along with the upper and lower shrouds. For details, please refer to the procedure found earlier in this section.
- Remove the accessory drive belt pulley-to-damper bolts, then remove the pulley. On some models the center bolt (torsional damper bolt) is equipped with a LARGE flat washer which would prevent removal of the pulley. On these engines the pulley cannot be removed until the next step has been completed.
- Remove the damper-to-crankshaft bolt. If removal is difficult, you have 2 options. The first is to hold the crankshaft from turning (on M/T vehicles this can be done by blocking the wheels, setting the parking brake and putting the van in gear. On A/T vehicles you must use a flywheel holding tool.). The second option is to cheat the bolt through impact (an air ratchet is best, though a sharp blow on the end of a wrench or breaker bar may also do the trick) or through using a penetrating oil. If the various special tools mentioned before are not available, apply penetrating oil to the bolt and allow it to sit overnight (this usually does the trick).
Using the a suitable torsional damper puller/installer tool (NOT AT JAWED TYPE) draw the damper from the end of the crankshaft.
NOTEWhen performing this operation, ALWAYS replace the front oil seal with a new one.
Inspect the damper (oil seal surface) for rust or burrs; remove the roughness with fine emery cloth.
When installing the damper onto the crankshaft, be careful not to damage the front oil seal.
Lubricate the hub with engine oil, align it with the keyway and install it onto the crankshaft. Use the torsional damper puller/installer tool to slowly draw the damper into position..
NOTEIf the tool is not available you MAY be able to align the damper and thread the retaining bolt a few turns, then use the hub retaining bolt to draw the damper into position. Be careful that sufficient threads are engaged first or you could strip the threads on the bolt or shaft. If the bolt cannot be started (because the distance is too great) obtain a second bolt of the same thread size, but of a longer length. You may also need some thick flat washers (in case the bolt is too long).
NOTEREMEMBER that the damper retaining bolt on some models MUST be installed AFTER the pulley (or stated another way, you may have to position the pulley before installing the damper bolt.
- Tighten the damper hub-to-crankshaft bolt to 70 ft. lbs. (95 Nm)
If not done already, position the accessory drive belt pulley, then secure using the retaining bolts.
- Tightening torque 43 ft. lbs. (58 Nm)
- If removed, install the lower shroud, followed by the engine cooling fan and upper shroud.
- Install the drive belt(s), then check and/or adjust the belt tension as applicable.
- Start the engine, then check for leaks or normal operation.