TM 10-3930-669-34 2-16.  GENERAL DISASSEMBLY INSTRUCTIONS. a. Cleanliness.    Work  area  must  be  as  clean  as  possible  to  prevent  contamination  of  components.  Hydraulic components, engines, transmissions, and axles require extremely clean work area when disassembled. b. Locking Parts.  Replace all lock wire, lock washers, cotter pins, and lock nuts at time of disassembly. Self-locking fasteners that are loosened must be replaced, when loosened or removed. c. Expendable Parts.  All gaskets, packings, and seals removed during repair must be discarded and replaced with new parts. d. Removing Seals.  Be sure all traces of oil, gaskets, and sealants are removed from components.  When possible, use wood or plastic probes and scrapers to prevent damage to machined surfaces. CAUTION Do not use tape to close off fuel or oil openings.  Sticky surface of tape can mix with fuel and oil and cause engine malfunctions. e. Parts Protection.  To keep dust, moisture, and other objects out of internal parts of the system or components, cap or tape over tubes, hoses, air lines, fittings, and component openings as soon as part is removed.  Wrap all removed parts in clean paper or dip parts in preservation oil. 2-17.  GENERAL CLEANING INSTRUCTIONS. WARNING • Dry-cleaning  solvent  (P-D-680)  is  TOXIC  and  flammable.    Wear  protective  goggles  and gloves; use only in a well-ventilated area; avoid contact with skin, eyes, and clothes; and do not breathe vapors.  Keep away from heat or flame.  Never smoke when using solvent; the flashpoint for type I dry-cleaning solvent is 100°F (38°C) and for type II is 138'F (50'C). Failure to do so may result in injury or death to personnel. • If  personnel  become  dizzy  while  using  cleaning  solvent,  immediately  get  fresh  air  and medical help.  If solvent contacts skin or clothes, flush with cold water.  If solvent contacts eyes, immediately flush eyes with water and get immediate medical attention. • Never  use  fuel  to  clean  parts.    Fuel  is  highly  flammable.    Serious  personal  injury  could result if fuel ignites during cleaning. a. Cleaning  Solvents.    Use  only  approved  cleaning  solvents  to  clean  parts.    Dry-cleaning  solvent  P-D-680  is commonly used.  Always work in a well-ventilated area. 2-89