Table 2-2. Operator/Crew Preventive Maintenance Checks and Services (Contd). ITEM NO. INTERVAL ITEM TO CHECK/ SERVICE PROCEDURE NOT FULLY MISSION CAPABLE IF: TM 9-2320-386-10 Change 1 2-33 28 After Master Operation cylinder (Contd) reservoir a. Check master cylinder reservoir a. Any leakage (6) for leaks. is evident. b. Check brake fluid level in master cylinder reservoir (6) through clear sides. Brake fluid level should be at bottom ring of master cylinder reservoir opening. Add fluid as required. WARNING Thoroughly clean exterior of mas- ter cylinder reservoir caps before removing. Dirt, water, or grease will contaminate brake fluid, causing brake system failure and injury to personnel. 6 LUBRICANT MIL SYMBOL (NATO CODE) SPECIFICATION BFS (H-547) All Temperatures MIL-B-46176 EXPECTED TEMPERATURES