TM 10-3930-659-34 4-8. IDLER GEARS MAINTENANCE (Con’t). b. DISASSEMBLY CAUTION DO NOT remove springpins unless damaged. Removal may damage parts. NOTE Upper and lower idler gearshafts are disassembled the same way. Lower idler gearshaft is illustrated. Remove springpin (20) from lower idler gearshaft (4). c. CLEANING AND INSPECTION WARNING Dry cleaning solvent, P-D-680, is toxic and flammable. Always wear protective goggles and gloves, and  use  only  in  a  well-ventilated  area.  Avoid  contact  with  skin,  eyes,  and  clothes,  and  DO  NOT breathe vapors. DO NOT use near open flame or excessive heat. The solvent's flash point is 100°F- 138° F (38°C-59°C). If you become dizzy while using cleaning solvent, immediately get fresh air and medical help.  If solvent contacts eyes, immediately wash your eyes and get medical aid. 1. Clean upper and lower idler gears with dry cleaning solvent and allow to dry. 2. Clean oil passage holes with nonelectrical wire and flush with dry cleaning solvent. Dry with clean rags. 3. Clean all other parts with dry cleaning solvent and dry with clean rags. 4. Inspect all metal parts for cracks, bends, and breaks. Replace cracked, bent, or broken parts. 5. Inspect all threaded parts for damaged threads. Repair damaged threads with die and tap threading set. 6. Inspect upper and lower idler gears for burrs, abnormal wear, and damaged teeth. Remove burrs with sharpening stone. Replace upper or lower idler gear if otherwise damaged. TA708082 4-39