Chevrolet 12624549 Cylinder Head Assembly (Service Partial)

Before you pull the cylinder head, unplug the clamp that is fastened on the negative terminal of the vehicle battery then, lift the vehicle using a jack and prop it safely on two jackstands. Remove the radiator and intercooler hoses and replace the water and oil, remove the exhaust pipes from the manifold and lower the car. Subsequently, take out the lower intake manifold, rocker arms, pushrods, and the exhausts manifolds. If removing the left head, remove the dipstick tube by undoing the bolt securing it to the front cylinder head. For the right cylinder head, fuel line support bracket and alternator are to be removed. Turn the spark plugs out then slacken each cylinder head bolt 1/4 turns at a time in a sequence opposite to the tightening sequence for better controls; the bolts will have to be discarded as they will have to be replaced with new ones during reassembly. The final tip is to always make sure the engine has cooled before you get a hold of the bolts. Finally, lift the head(s) off the engine, being particular not to mar the mating surfaces and where further pressure is encountered knock off the gasket with the help of a hammer and wooden block. burial: the head, in particular, should be put on wooden blocks to avoid any harm. For installation, it is mandatory that the mating surfaces of each cylinder head and block be free of contaminants, this being accomplished by using a gasket scraper to remove all deposits of carbon and old gasket and after this use lacquer thinner or acetone. Inspection of the block and head mating surfaces involves a file for slight imperfections that are not easily machined. Clean out the threads in the head bolt holes with a tap over the head bolt size. Place the new gasket on the location where the dowels pins are located in the block to make sure it is placed the right way up; now carefully place the head onto position in the block without shifting the gasket. New cylinder head bolts should be fitted and tightened following the sequence at the recommended torque while each bolt should be turned to the recommended angle in the sequence the same as the torque tightening sequence. The other steps are the reversed of the above removal and lastly replace the engine oil and filter.

Before starting, ensure the engine is entirely cool to prevent head warpage. Acquire new head bolts in advance. Disconnect the negative battery cable. Allow the engine to cool completely, and then drain the cooling system.