TM 9-2330-392-14&P Change 2 4-7 4-10 CLEANING AGENTS (Con’t). b. Prior to using water to clean, ensure master cylinder fill cap is tightened. c. Allow wet brakes to dry before using trailer. 4-11 LEAKAGE DEFINITIONS FOR UNIT PMCS. Wetness around seals, gaskets, fittings, or connections indicates leakage. A stain also denotes leakage. Use the following leak- age classes to determine the status of the trailer. When in doubt, notify your supervisor. CAUTION Operation is allowable with Class I or II leakage except for brake systems. Any brake fluid leakage must be corrected. Any Class III leakage must be corrected. Failure to do so may result in damage to the equipment. a. Class I. Leakage indicated by wetness or discoloration not great enough to form drops. b. Class  II.  Leakage  great  enough  to  form  drops,  but  not  enough  to  cause  drops  to  drip  from  item  being checked/inspected. c. Class III. Leakage great enough to cause drops that fall from the item being checked/inspected. Table 4-1. Unit Preventive Maintenance Checks and Services for M1101, M1102, and Trailer Chassis Item No. Interval Location Procedure Not Fully Mission Capable If: Item To Check/ Service 1 Semi- annual Lunette a. Measure  lunette  ring  thickness.  If  mea- surement    is    less    than    5/8”,    replace lunette (para 4-27). a. Lunette ring thickness is less than 5/8”. b.    Inspect master pin slotted hole for wear. If  hole  length  exceeds  2.313  inches  or hole  width  exceeds  1.20  inches,  replace lunette (para 4-28). b.    Wear limits are exceeded. 2 Semi- annual Brake Actuator Assembly a. Inspect master pin hole for wear. If hole diameter   exceeds   1.06   inches,   replace outer case assembly (para 4-27). a. Wear limits are exceeded. b.    Inspect front roller pin hole for wear. If hole diameter exceeds 0.75 inch, replace outer case assembly (para 4-27). b.    Wear limits are exceeded. c. Remove and disassemble hydraulic brake actuator assembly (para 4-27). c. Wear limits are exceeded. 3 Semi- annual Tires a. Visually   check   for   underinflated   and unserviceable tires. Check tires for leaks, cuts, gouges, cracks, or bulges. Remove all penetrating objects. a. Any  tire  is  missing  or  unservice- able. Tires have leaks, cuts, gouges,   cracks,   or   bulges   which would result in tire failure during operation.