GMC 12634223 Cylinder Head Kit (H.O. Ly7, Rh)(No Valves, Etc)

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Start by detaching the negative battery cable and relieving the fuel system pressure in order to change the cylinder heads. After that, empty out the cooling system and remove the engine/transaxle assembly. From there, take off the intake manifold(s), valve covers, and upper timing chains. Based on which head is being removed, ground wires should be disconnected from heads as well as different connectors and hoses. The head bolts must be slightly unscrewed following a particular order thereafter removed by hand while their lengths and positions are noted down. It is important to carefully lift these parts from above this machine avoiding prying them away since they should then be standing on wooden blocks. For installation, ensure mating surfaces on both cylinder heads and block are clean; use gasket removal solvents when necessary. Thoroughly clean up all surfaces in order to prevent oil-related sealing problems as well as clear debris from the cylinders. Inspect these areas for damage and fix it where necessary also chase threads with brake cleaner or clean thread holes in head bolt holes to produce right torque readings. Put new gaskets over dowels in block; then put these heads back without moving gaskets very much. Use thread locking compound to cover threads for new 8 mm head bolt(s). Then tighten these new 11 mm head bolts according to torque specifications followed by angle of rotation specified sequence having previously installed them finger-tight onto these newly coated threads with this substance named thread lockers. To complete reassembly follow this dismantling process backwards including installing again engine/transaxle assembly, replacing engine oil filter also refilling coolant however lubricant compartment respectively at last begin its startup operation before inspecting water or oil leakages if any present within that mechanism's working system.