Patent ID: 6546347
Filing Date: 2003-04-08
Classification: F01L,Y10T

Abstract:
A method of setting a predetermined clearance in an internal combustion engine between a rocker arm and a rocker arm actuated engine component, in which a rocker arm is rotatably mounted on a rocker shaft for reciprocating movement relative thereto, the rocker arm having a first end located on a first side of the rocker shaft and a second end located on a second side of the rocker shaft, the first end of the rocker arm having an adjustment screw extending therethrough to act on an end of a push rod, the second end of the rocker arm being movable in a first, component-actuating, direction and in a second direction opposite to said first direction and having a component engaging surface co-operating with a portion of the rocker arm actuated engine component, at least a portion of the rocker arm actuated engine component being biased in said second direction towards a first position and being movable against the bias in said first direction towards a second position, the method comprising the steps of:(a) setting the rocker arm to a zero position and recording said zero position as a reference datum; (b) rotating the adjustment screw to adjust the position of said rocker arm to a first reference position; (c) rotating the adjustment screw through a reference angle and recording a corresponding second reference position thereof; (d) calculating a coefficient from the difference between said first and second reference positions and said reference angle; (e) using said coefficient to calculate an angular rotation of the adjustment screw corresponding to said predetermined clearance; and (f) rotating the adjustment screw on the basis of said calculated angular rotation to set the predetermined clearance relative to said reference datum.