GM 12674581 Balancer Assembly, Crankshaft

In order to undertake this procedure one is forced to buy a harmonic balancer bolt and a balancer installation tool which is only supplied by special tool makers. To start with, the following steps may be followed; the cable connecting the battery to the negative terminal should be disconnected. Chock the wheels which are still in contact with the ground and then locate the front of the car and lift it up using jackstands. The drivebelts and the splash shield must be removed to provide access to the motor mounts. Then proceed to the removal of the starter motor by using a prybar through the rear of the engine block to hold the ring gear teeth on the flywheel as the harmonic balancer pulley center bolt is loosened. To have the harmonic balancer ready without the balancer, the three-jaw puller is required; the jaws of the puller should be adjusted only to embrace the cylindrical part of the balancer, the outer ring should not be touched; by this time, you have to put an elongated bolt with the Allen's head into the cranking nose in order to protect the threads. Apply clean engine oil to the end of the crankshaft and oil seal before fitting the harmonic balancer onto the crankshaft so that the slot in the hub of the pulley/balancer is aligned to the Woodruff key. Place the crankshaft between your legs and with some help use the old balancer bolt to push the balancer on to the crankshaft. Replace the balancer bolt with a new one, and then tighten this bolt at the particular torque and with the predetermined angle of turn; for this action, a torque angle gauge is required. The other part of the installation is removal and it is done in the reverse sequence.

This procedure needs a new harmonic balancer bolt and a balancer installation tool that is accessible justified by specialized tool makers. First of all, you should pull the cable with the negative connection end off the battery. Lift up the front part of the vehicle until the weight is being borne on jackstands securely. Take out the belts and the splash shield. Third, take off the starter motor, turning the ring gear teeth on the flywheel/driveplate with a prybar coming through the rear of the engine block while loosening the center bolt of the harmonic balancer pulley. It is recommended that the balancer be pulled off the crankshaft with a three-jaw puller; it is important that the jaws do not grip the outer ring of the balancer but rather the hub of it. So as to avoid damaging the threads of the crankshaft, extend an Allen-head bolt into the crankshaft nose in which the taper of the puller will bear. Clean the oil seal end of the crankshaft with clean engine oil and then place the crankshaft pulley/harmonic balancer on the crankshaft making sure that the groove in the hub fits to the Woodruff key. Take the crankshaft and make sure that it is held firmly and try using the previous harmonic balancer bolt to fix the balancer on the crankshaft. Replace a harmonic balancer bolt and tighten to the next specified torque and angle in a two-step sequence with the torque angle gauge. The continuation of the installation is done in the reverse of the removal processes followed above.

This procedure requires a new crankshaft balancer bolt and special balancer installation tools J 41665 and EN-47812, which are available through specialized tool manufacturers only.

Use the specialized crankshaft balancer installation tool to press the crankshaft pulley/balancer onto the crankshaft, then install the old crankshaft balancer bolt and tighten it to 240 fl-lbs (330 Nm).