2002 chevy traailblazer head gasket replacement and put it back to gether
If you are asking how to do this, it is not easy, it is very complex and takes a long time. The big points: Drain the coolant, disconnect battery, take off the intake manifold, take of the exhaust manifold, remove the head, clean the head and check for warp and cracks, clean the block and remove all debris from cylinders, install gasket, put head back on, put manifolds back on, replace coolant, change oil, connect the battery. You may have issues with bolts that break or strip out the block, you should send the head in to be checked, the valves and springs should be checked and those seals replaced, you need special tools and reference materials.