TM 9-2320-209-20-3-4 23-12. POWERPLANT HEATER EXHAUST TUBE REMOVAL AND REPLACEMENT. TOOLS: 7/16-inch wrench (2) 6-inch pliers 1/8-inch punch SUPPLIES: None PERSONNEL: One EQUIPMENT CONDITION: Truck parked, engine off and cool, handbrake set. a. Preliminary Procedures. (1) Open hood and right side panel. Refer to TM 9-2320-209-10. (2) Open powerplant heater box door. Refer to para 23-22. WARNING Do not work on hot exhaust tube. Personnel can be badly burned. b. Removal. FRAME 1 1. Using pliers, take out and throw away cotter pin (1). Take exhaust tube (2) off elbow (3). GO TO FRAME 23-30