F 250 4WD Super Duty V10-6.8L VIN S (2001)
Variable Valve Timing Actuator: Description and Operation
Variable Cam Timing (VCT) Unit Assembly
Variable Cam Timing (VCT) Unit Assembly
Variable Cam Timing Unit Assembly
The variable cam timing unit assembly (Figure 131) is coupled to the camshaft through a helical spline in the VCT unit chamber. When the flow of oil
is shifted from one side of the chamber to the other, the differential change in oil pressure forces the piston to move linearly along the axis of the
camshaft. This linear motion is translated into rotational camshaft motion through the helical spline coupling. A spring installed in the chamber is
designed to hold the camshaft in the minimum overlap position (5 degrees) when oil pressure is too low to maintain adequate position control. The
camshaft is allowed to rotate up to 30 degrees.
