REMOVAL & INSTALLATION
See Figures 1, 2, 3 and 4
Most of the 4.3L engines covered in this guide are equipped with a crankshaft hub and pulley assembly. The pulley is usually mounted to the hub using 3 or so bolts around the inner circle of the pulley. The center mounting bolt is used to retain the hub to the crankshaft, but may also be used to retain the pulley. If the center mounting bolt also retains the pulley, a washer can normally be seen between the bolt head and the inner lip of the pulley.
- Disconnect the negative battery cable.
- Loosen and remove the accessory drive belts or serpentine drive belt from the crankshaft damper.
- If necessary for access on certain models, remove the fan assembly.
- Remove the pulley mounting bolts from the pulley and damper assembly. If the center mounting bolt is not used to retain the pulley, it may be separated from the hub at this time and removed from the engine.
- Spray the damper bolt with penetrating oil and allow it to soak in for at least a few minutes. Loosen and remove the center crankshaft damper bolt. If the pulley was not removed earlier, it should be free now.
If damper bolt removal is difficult, various methods may be used to hold the crankshaft while loosening or tightening the bolt. One method involves installing a flywheel holding fixture to prevent the crankshaft from turning. A holding tool may be available for some dampers which threads into the pulley bolt holes. But most importantly of all, allow the penetrating oil to do the work when loosening an old damper bolt and reapply oil, as necessary. If you have the time, you might even want the oil to sit overnight.
- Remove the damper from the end of the crankshaft using a suitable threaded damper puller, NOT a jawed-type puller which would most likely destroy dampers with bonded hubs.
- If removal of the damper was difficult, check the damper inner diameter and the crankshaft outer diameter for corrosion. A small amount of corrosion may be removed using steel wool, then the surface may be lubricated lightly using clean engine oil.
- Coat the front cover seal contact edge of the damper lightly with clean engine oil, then apply a small amount of RTV sealant to the keyway in the damper hub. Install the damper on the end of the crankshaft (along with the pulley if the share the center retaining bolt), but DO NOT hammer it into position, instead use a damper installation tool to slowly draw the hub into position. If the damper can be positioned far enough over the end of the crankshaft, the damper bolt may be used to draw it into position, but be careful that sufficient threads are in contact to prevent stripping the bolt or crankshaft.
- Once the damper is fully seated, install and tighten the retaining bolt to 74 ft. lbs. (100 Nm).
- If not done earlier, install the pulley and secure using the outer retaining bolts. tighten the pulley bolts to 43 ft. lbs. (58 Nm).
- If removed for access, install the fan assembly.
- Install the drive belt(s) to the crankshaft pulley.
- Connect the negative battery cable.
See Figures 5, 6 and 7
- Disconnect the negative battery cable.
- Remove the serpentine drive belt.
- Remove the fan shroud and the engine cooling fan.
- Raise the vehicle and support it with jackstands.
- Remove the crankshaft pulley bolts.
- Unfasten the hub bolt and remove the pulley.
- Attach a suitable puller tool to the crankshaft hub.
- Turn the center screw of the puller clockwise until it forces the hub from the crankshaft.
- Inspect the hub for damage and replace it as necessary.
- Inspect the crankshaft key for damage and replace as necessary.
- Coat the front cover seal with clean engine oil.
- If removed, apply a suitable RTV sealer to the key on the crankshaft and install the key.
- Plave the hub onto the crankshaft making sure to align the key with the notch on the inside diameter of the hub.
- Using either crankshaft hub installation tool J 29113, its equivalent, or the pulley hub bolt, pull the hub into position. If you use the pulley hub bolt to install the be careful that the hub goes in straight. Once the hub is fully seated, screw two of the pulley bolts into the nub, use a prybar between the bolts to stop the hub from turning and loosen the hub pulley hub bolt.
- Remove the two pulley bolts and install the pulley.
- Install the pulley hub bolts and the center hub bolt. Tighten the pulley bolts to 37 ft. lbs. (50 Nm) and the pulley hub bolt to 77 ft. lbs. (105 Nm).
- Lower the vehicle.
- Install the cooling fan and the radiator shroud.
- Install the serpentine drive belt and connect the negative battery cable.