STARTER
MOTOR
FWD ACCESSORY GEARBOX SECTION
B
APU Engine Component Location Figure 1 (Sheet 1)
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. AIRPLANES WITHOUT ETC ú
49-21-00
ú ú 01 Page 2 ú Mar 15/92
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
TURBINE SECTION
EXHAUST PORT TURBINE PLENUM BLEED AIR PORT COMPRESSOR SECTION
GEARBOX ACCESSORY SECTION SEE A
SEE B
COMBUSTION
CHAMBER OIL
COOLER
OIL
TANK COMPRESSOR FIRST STAGE COMPRESSOR PLENUM FWD AIR INLET FLANGE
A
FUEL CONTROL
UNIT OIL
PUMP
APU ELECTRICAL
GENERATOR
OIL
TANK
CROSSOVER
DUCT FOR THE
COOLING AIR
STARTER
MOTOR
FWD
ACCESSORY GEARBOX SECTION
B
APU Engine Component Location Figure 1 (Sheet 2)
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. AIRPLANES WITH ETC ú
49-21-00
ú ú 01 Page 3 ú Mar 15/92
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / GTCP85-129 SERIES /737-300/400/500/ ENGINES/MAINTENANCE MANUAL ////////////////////////
4. Gearbox Section (Fig. 1)
_______________
A. The gearbox section changes the high turbine speed of the APU to a lower speed to turn the necessary components of the APU. The gearbox section is found at the forward end of the APU. The gearbox section has the accessory drive. The accessory drive has a gear train that is installed in a housing. The gear train is turned by a quill shaft. The quill shaft is connected to the shaft that turns the compressor impeller and turbine wheel. The gears in the gearbox section are lubricated by spray from the oil in the gearbox. For a more detailed description of the APU lubrication system, refer to AMM 49-91-00/001.
B. The gearbox section has the mounting pads for the fuel control unit, starter motor, cooling fan, tachometer generator, oil pump, and APU electrical generator. For a more detailed description of these components, refer to the following:
-
APU Fuel System, AMM 49-31-00/001
-
APU Ignition and Start System, AMM 49-41-00/001
-
APU Cooling Air System, AMM 49-51-00/001
-
APU Controls, AMM 49-61-00/001
-
APU Lubrication System, AMM 49-91-00/001
-AC Generation System, AMM 24-21-00/001.
