scarifying assembly 19 may be removed from the chassis 2 of the vehicle 18 in order to reduce the size of the scarifying apparatus this allows the components of the scarifying apparatus to enter a sewer system pipe or passageway through a small aperture such as a manhole similarly the width of the track assembly 1 can be reduced to assist the chassis 2 to pass through a manhole and access an interior of a pipe 34 the arm 7 includes adjusters 6 to raise or lower the fluid coupler 9 to align it approximately with the cross sectional center of the pipe this alignment ensures the interior walls of the pipe are evenly scarified the arm 7 is coupled to a stabilizing bar 8 to counteract the weight of the arm 7 and the scarifying assembly 19 in front of the vehicle 18 the fluid nozzle assembly 10 is secured to the arm 7 the fluid coupler 9 having a flow control valve not shown is coupled to an external source of fluid under pressure not shown the pressurized fluid is fed into an exchanger actuator 13 referring to fig6 the exchanger actuator 13 causes the fluid nozzle assembly 10 to rotate or oscillate and distributes the fluid to each branch 14 of the fluid nozzle assembly 10 the fluid nozzle assembly 10 rotates in the direction indicated by arrows 22 and 23 the branches 14 are axially extendible each of the branches 14 being replaceable with branches of a desired length in order to bring the fluid nozzles 15 which are mounted on the ends of the branches 14 into proximity with the.