Abstract: A method and apparatus is disclosed for continuing the cooling of an engine, such as a turbo-charged equipped truck engine, at times when the engine temperature is elevated. In the illustrated form of the invention, the temperature of the engine is sensed. An engine control circuit bypasses the ignition switch at times when the sensed engine temperature is above a predetermined temperature and prevents the ignition switch from shutting off the engine under such conditions. The engine continues to operate, even though the ignition switch is off, until such time as the engine cools and the sensed temperature drops to the predetermined reference level. The predetermined temperature is adjustable to vary the temperature at which the engine is allowed to shut off. The apparatus includes optional indicator and override mechanisms.

Abstract: A control valve has a first position in which it directs air under pressure to a wiper motor through a "run" line to actuate the motor to oscillate the wiper. The control valve has a second position in which it directs air through a park line to a valve complex which routes air unidirectionally to the motor to cause the wiper to assume a "park" or rest position. An overriding valve is interposed in the "park" line and is connected to the air pressure source. This valve is of the solenoid type and is intermittently operated by a timer upon its actuation to dispose the overriding valve in a first position in which the flow of "park" air through the override valve is interrupted for a brief period, to allow "run" air pressure to actuate the wiper in normal fashion, and then dispose the valve in a second position in which the "park" air is routed to the motor to temporarily halt the operation of the wiper. This sequence continues so long as the timer remains actuated.