P r e v e n t i v e M a i n t e n a n ce Checks and Services for M48A15 AVLB Hull - C o n t i n u ed

TM 5-5420-226-20-1 P r e v e n t i v e M a i n t e n a n c e C h e c k s a n d S e r v i c e s f o r M 4 8 A 5 A V L B H u l l - Item No. 47 Interval Semiannual Location Item to Check/Service Fixed Fire Extinguisher System - Continued C o n t i n u e d Procedure Not Fully Mission Capable if: Step 13 If there is no CO₂discharge whatso- ever, check for trapped high pressure gas. WARNING Relieve system of high (800-1800 psi) pressure gas slowly. Wear gloves and eye ‘protection. Avoid breathing vapor. Failure to comply may result in injury or death to personnel. Loosen any fitting between delay valve and check valve. If trapped gas escapes, replace all three check valves and repeat step 7. If no gas escapes, tighten fitting. Loosen any fitting between the CO₂ cylinder and delay valve. If gas es- capes, replace discharge delay bottle assembly (page 20-57). Remove No. 1 CO₂cylinder (page 20-53). Tag cylin- der and send to support maintenance for recharging. Reset control handle and reset control valve. Replace No. 1 CO₂cylinder (page 20-53). Repeat steps 7 through 11. Remove multimeter from accessory test cable. Remove accessory test ca- ble from engine accessory control harness. Reset control handle, reset control valve and replace No. 1 CO₂cylin- der. Fixed fire extin- guisher system does not operate properly. Change 6 3-87