Service Procedure        

GM-21867-6 allows the technician to measure the engine oil pressure with GM-21867-A Oil Pressure Gauge kit under a variety of engine running conditions to determine the mechanical condition of the engine. GM-21867-6 is threaded into the engine block in place of the oil pressure sending unit and adapter, and the oil pressure gauge from GM-21867-A is then connected to GM-21867-6. The engine can be started, and the oil pressure monitored. Used with GM-45299 to pre lube.