Before removing the exhaust manifold it is recommended to disconnect the negative terminal of the battery, engage the parking brake, and place chocks to the rear wheels. Lift the front end of the railroad vehicle until it is off the wheels and properly supported by jackstands. Pull off the nuts on the under side that attached the exhaust system on the exhaust manifold and apply penetrating oil on the bolt so that it can be easily removed. For air conditioning models remove the compressor drive belt and the lower adjusting brace if required. Disconnect the oxygen sensor wire at the connector, loose the nuts and bolts that fastens the heat shield to the exhaust manifold and finally, remove the heat shield. If supplied, remove the air injection tube. Pour some penetrating oil on the threads and then remove the bonnet bolts or nuts that secure the exhaust manifold, this will disconnect the exhaust pipe from the manifold where two bolts are required. Bolt the manifold to the
Cylinder Head, inspect any threaded fasteners and remove all gasket material from the surfaces while looking out for crack. As for the installation, a new gasket must be placed on the cylinder head, and the openings should be properly oriented; then, the manifold must be installed and fasteners tightened in several passes with uniformly in the middle and then towards the ends to the required torque. Replace what is left in reverse sequence and fit a new exhaust pipe seal and gasket; final step is to start the engine and look for exhaust leak.