What was found
(CAN) A STUDENT PILOT REPORTED TO MAINTENANCE THAT ON A GROUND RUN OF THE AIRCRAFT THAT THE PROPELLER WOULD NOT CYCLE WHEN THE CONTROL WAS PULLED OUT TO PUT THE PROP INTO COARSE PITCH. INVESTIGATION FOUND THAT THE PROP CONTROL FLAT SPRINGS THAT HOLD THE PROP CONTROL SYSTEM RIGID HAD BROKEN. THESE SPRINGS GO THROUGH MANY CYCLES AND BREAK WHEN THEY ARE STRESSED. NEW SPRINGS WERE INSTALLED WITH NO STRESS BETWEEN THE BRACKET AND THE SUPPORT, AND THE PROP FUNCTIONED PROPERLY ON THE RUN-UP.