TM10-3930-660-20 5-10. FUEL/HYDRAULIC TANK - SERVICE This  task  covers: a. Service by draining and filling tank with fuel. b. Service by draining and filling tank with hydraulic oil. Initial Setup Tools Tool Kit, Automotive Mechanics Materials/Parts Diesel Fuel (App. C, Item 17) Drain Pan Equipment  Condition Hydraulic Oil (App. C, Item 35) Vehicle parked on level ground. SERVICE BY DRAINING AND FILLING TANK WITH FUEL Fuel side of fuel/hydraulic tank (1) contains 44 gallons of fuel when full. 1. REMOVE DRAIN PLUG  (2) FROM FUEL SIDE OF FUEL/HYDRAULIC OIL TANK (1) AND ALLOW FUEL TO DRAIN. a. b. c. d. Open cap (3) at top of fuel/hydraulic tank (1). Place suitable drain pan under fuel side of fuel/hydraulic tank. Remove drain plug (2) from fuel side of fuel/hydraulic tank (1). Allow fuel to drain completely. 2. INSTALL DRAIN PLUG (2) TO FUEL SIDE OF FUEL/HYDRAULIC TANK (1) AND FILL TANK (1) WITH FUEL. a. Install drain plug (2) to fuel side of fuel/hydraulic tank (1). b. Fill fuel side of fuel/hydraulic tank (1) with fuel. C. Install cap (3) at top of fuel/hydraulic tank (1). 5-22