Abstract: Apparatus and methods for flushing and cleaning the oil strainer and crankcase of an internal combustion engine of a type having a removable full-flow oil filter. The oil filter is temporarily replaced with a cartridge which has at least one passage therethrough which will communicate with the discharge side of the engine oil pump but does not communicate with the normal outflow port of the filter apparatus. A second passage therethrough may communicate with the outflow port of the filter system but does not communicate with the discharge of the oil pump. In a preferred method, the inlet of the first passage may be connected to a source of pressurized fluid to force the fluid, in a direction opposite to normal flow, through the passage, the oil pump and the oil strainer to agitate and flush contaminants in the oil strainer and crankcase. The pressurized fluid and contaminants are drained from the crankcase after which the cartridge is removed, a new oil filter installed and clean oil added to the engine.

Abstract: Locking apparatus for a ram type blowout preventer having a housing with a passageway through which a tubular member may pass; rams movable between a non-sealing position in the housing, in which the passageway is open, and a sealing position in which the passageway is sealingly closed; and an operator assembly for moving the rams between the non-sealing and sealing positions. The locking apparatus may comprise: at least one rod connected to the operator assembly reciprocable between first and second terminal positions in response to movement of the rams between their non-sealing and sealing positions, respectively; and locking means engageable with the rod when in its second terminal position to lock the rams in their sealing positions. A method of operating such a ram type blowout preventer is disclosed also.