GM 12629058 Cylinder Head

To take away the cylinder heads, initially disconnect the battery cable and let out the cooling system while making sure that fuel system pressure is relieved. Unfasten intake manifold, coolant pipe, exhaust manifold(s), valve cover(s), rocker arms, pushrods as well as coolant air bleed pipe. For the left cylinder head, remove alternator with its bracket and detach ground strap from back of cylinder head. For right cylinder head take off dipstick tube and disconnect ground cables from front of cylinder head. Loosen the head bolts gradually in reverse order of tightening sequence until they can be removed by hand. Carefully remove the head(s) from the engine so as to prevent damage to mating surfaces. Put heads on blocks of wood for storing. When putting them back, ensure that both cylinder heads and block mating surfaces are clear of debris and clean up with a gasket scraper and brake cleaner checking for any possible machining damage as well. If necessary chase thread holes in block with a tap or brake cleaner followed by compressed air then replace all head bolts with new ones. Place new gaskets onto dowels in block before placing heads on top without interfering with position of gaskets then tighten head bolts to specified torque in recommended sequence using specified tools. Finally install coolant pipe using new gaskets; proceed to reverse removal steps thereafter; add coolant; change oil and filter; start engine & check for proper operation/leaks.