GM 12565413
Camshaft

The Camshaft can be replaced by disconnecting the negative Battery Cable, draining the cooling system, and removing the Radiator and A/C Condenser. The next step is to take off the valve lifters, timing chain, Camshaft sprocket, and balance shaft drive gear, as well as the Camshaft retainer bolts and retainer. Exercise caution as all Camshaft journals are of the same diameter in order to prevent damage to Camshaft bearings. Unscrew the engine Camshaft by installing three (5/16-18 x 4.0 inch) bolts to the front bolt holes, turning the Camshaft and dumb-bells as a carrying handle to pull carefully the Camshaft out of the bearings, then unscrew the Camshaft carrying bolts and clean the Camshaft and bearings. Use new Camshaft, change the oil and Oil Filter, and fill with gm engine oil supplement (GM P/N 1052367) or similar. It is also necessary to put clean engine oil (GM P/N 12345610 or equivalent) or engine oil supplement (GM P/N 1052367 or equivalent) on the Camshaft lobes, bearing journals, and bearings. Remove the bolts that are being used as a handle to install the engine Camshaft. When reusing fasteners, treadlock (GM P/N 12345382 or equivalent) onto the threads of the Camshaft retainer bolts and then install the Camshaft retainer and the bolts and tighten it to 12 nm (106 inch lbs.). Do not forget to install the balance shaft drive gear, timing chain, Camshaft sprocket, and valve lifters, and the A/C Condenser and the Radiator. Finally, fill the cooling system, refuel the air conditioning system, and reconnect the negative Battery Cable.