GMC 12625440 Camshaft

To take off the camshaft, first disconnect the cable from the negative battery terminal and release fuel system pressure. From there on, remove; radiator, auxiliary automatic transmission fluid cooler (if equipped), power steering cooler, air conditioning condenser, valve covers, intake manifold, rocker arms, pushrods, timing chain and sprockets, and cylinder heads. Before you remove the lifters arrange to store them in a labeled container. Remove lash adjusters and camshaft retainer plate using a bolt as a handle to carefully pull out camshaft. To check out the camshaft measure lobe height and base circle for lobe lift determination; compare with specifications and replace the camshaft if necessary. Check the camshaft bearing journals for wear or damage; use a micrometer to measure them. Inspect the camshafts lobes for discoloration; score marks; chipped areas; unalike wear. Clean and inspect lash adjuster bodies for damage, wear and proper roller function. Put in place by lubricating bearing journals and lobes with assembly lube before sliding it into the engine, securing it with the Cam Thrust Plate. Install timing chain and sprockets , camshaft position sensor, lash adjusters As well as this refill cooling system, change oil, new oil filter installation precede start up-run engine process.