Engine valve and seat burnishing system

Abstract

An arrangement for exercising (or burnishing) the intake and exhaust valves in the cylinder head of an internal combustion engine employs a plurality of out-of-phase eccentric cams coupled to a source of rotatory motion. The eccentric cams engage with respective linear drive arrangements that are urged into out-of-phase reciprocation with respect to each other. The linear drives urge the valves into repeated open and closed states where, in combination with valve rotators, burnishing of the sealing portion of the valves with the valves seats to improve the seal therebetween is effected. The use of eccentric cams to effect linear reciprocating motion achieves control over both directions of movement of the linear drive arrangements. The cylinder head is maintained in fixed relation to the linear drive arrangements by a hydraulic, pneumatic, or other form of ram, the ram also creating a test chamber. Thus, after the exercising of the valves is completed, the test chamber is pressurized with a fluid such as air, and the subsequent loss of pressure within the test chamber is indicative of the quality of the seal between the valve and the valve seats. Preferably, reciprocation of the linear drive arrangements is achieved by coupling a cam follower to a substantially annular eccentric protuberance having radially inward and outward surfaces. The application of excessive force is precluded by the use of springs within the linear drives.