Abstract: A reciprocating, preferably a piston-type, exhauster adapted for mounting on an engine crankcase and having, on opposite sides of the piston, a high clearance volume inlet chamber and a low clearance volume exhaust chamber. The piston is operated by an engine driven cam acting on the piston rod which passes through the exhaust chamber and moves against a return spring in the inlet chamber. As the piston moves in the cylinder air is drawn from the inlet chamber through a non-return valve in the piston to the exhaust chamber and then is discharged directly into the engine crankcase.

Abstract: A mechanical brake actuator comprises an output tappet (3) in screw-threaded engagement with a sleeve (7). In normal use, rotation of an operating member (17) by a rod or cable leads to axial advancement of the tappet (3) and sleeve (7) as a unit. Adjustment for wear is provided by rotating the sleeve (7) relative to the tappet (3) if, after a predetermined amount of rotation of operating member (17), the torque required to turn the sleeve (7) is below a predetermined value T. This is achieved by an adjuster comprising an input ring (25) coupled to an output member (29) by a torsion spring (28). The input ring (25) is coupled to operating member (17) by a lost motion connection (23,24) and output member (29) is coupled to sleeve (7) by a one-way clutch (30). After an amount of rotation of the operating member (17) predetermined by the lost motion connection (23,24) the operating member (17) entrains the input ring (25).