Abstract: A system for precisely measuring the amount of oil consumed during operation of an internal combustion engine includes a float chamber which communicates with an oil sump in the engine. A float is disposed within the chamber which moves upwardly and downwardly therein, depending upon the level of oil. A precision level detector is mounted in the upper end of the chamber for generating an electrical signal which is representative of the position of the float within the chamber. A microprocessor receives this signal, along with signals from various other sensors representing engine speed, engine torque, and oil temperature. In response thereto, the microprocessor controls the operation of a pump connected between an external supply of oil and the engine sump. When predetermined conditions are met, the microprocessor activates the pump to add oil from the system. The microprocessor also records the oil level over a period of time to determine the rate of oil consumption.

Abstract: A valve stem seal provides an elastomeric main valve body having an upper working portion and a lower support portion, the latter for support of the seal on a valve guide member. The seal contains a central helically threaded internal region adapted to meter oil flow betwen the valve guide and a valve stem reciprocally moveable with the guide. The upper working portion defines a pair of ends, wherein each end contains a non-threaded internal portion defining a plurality of alternately arranged axially extending grooves and ribs. The grooves provide oil flow passageways, while the ribs support the ends of the working portion against the reciprocal valve stem member. In a preferred form, the non-threaded internal portions have axial lengths within a range of one-tenth to one-third the axial length of the central threaded region.

Abstract: A unitary molded valve seal assembly includes a plastic body and an elastomeric seal which is molded in-situ within the plastic body. The plastic seal body preferably fabricated of Hytrel plastic and includes a plurality of obliquely oriented ribs or lips on its inside surface which seal against an engine valve guide. The elastomeric seal is preferably fabricated of Viton rubber and defines an irregular surface having curved regions which retain it within the seal body and a pair of spaced apart lips which sealingly engage the value stem.

Abstract: An apparatus for detecting relative movement between two objects which is illustrated in the preferred embodiment as a vehicle road speed signal source including a reed switch oscillator for generating an output signal having a frequency and a magnitude proportional to the road speed of an associated vehicle. Current flows through a biasing coil proximate the reed switch to generate a magnetic field which is slightly less than the field required to close the switch contacts. A permanent magnet means attached to the drive shaft of the vehicle generates a magnetic field which aids the biasing coil magnetic field to close the reed switch contacts. A transistor responds to the closing of the reed switch contacts to turn off the current to the biasing coil which allows the reed switch contacts to open.