3. While holding the motor unit with your hand, pull out knob 20 for stopper pin to release the lock of motor unit, andlift up the motor unit slowly until it comes to the free point from return force of torsion spring 28. See Fig. 3-5.4. Remove pipe 16-90 by pushing it out using socket wrench 10. See Fig. 3-6.5. Remove motor unit from front arm complete. See Fig. 3-7.[3] Mounting motor unit (blade case, motor housing, handle etc.) to front arm completeFig. 3-5Stopper pinKnob 20Push out pipe 16-90 using socket wrench 10as illustrated above.Fig. 3-6Pipe 16-90Socket wrench 10Fig. 3-7Front arm completeTorsion spring 28Sleeve 17Sleeve 17Fig. 4R epairP 6 / 261. Insert two sleeves 17 into torsion spring 28. See Fig. 4.2. Mount the motor unit to front arm complete. Refer to Fig. 3-7.3. Pass pipe 16-90 through the holes of front arm and blade case.Refer to Fig. 3-6.4. While keeping motor unit in the rest position, push knob 20 forstopper pin toward the blade case side. Refer to Fig. 3-5.5. Secure link plate with hex socket head bolt M6x20, and securethe pipe 16-90 with ring 6, flat washer 6 and hex socket head screwM6x10. Refer to Fig. 3-4.