B737NG/71/301Powerplant Boeing B737-600/700/800/900 Powerplant CFM56-7B Training manual For training purposes only page 1 LEVEL 3 31 - 08 - 2009 71-00-00 Rev : 2.1 B737NG/71/301 Training manual Powerplant This publication was created by Sabena technics training department, Brussels-Belgium, following ATA 104 specifications. The information in this publication is furnished for informational and training use only, and is subject to change without notice. Sabena technics training assumes no responsibility for any errors or inaccuracies that may appear in this publication. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of Sabena technics training. Contact address for course registrations course schedule information Sabena technics training
[email protected] EFFECTIVITY ALL 71-00-00 page 2 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant List of Effective Pages. 1.......................... 15 - 04 - 2009 33........................ 15 - 04 - 2009 2.......................... 15 - 04 - 2009 34........................ 15 - 04 - 2009 3.......................... 15 - 04 - 2009 35........................ 15 - 04 - 2009 4.......................... 15 - 04 - 2009 36........................ 15 - 04 - 2009 5.......................... 15 - 04 - 2009 37........................ 15 - 04 - 2009 6.......................... 15 - 04 - 2009 38........................ 15 - 04 - 2009 7.......................... 15 - 04 - 2009 39........................ 15 - 04 - 2009 8.......................... 15 - 04 - 2009 40........................ 15 - 04 - 2009 9.......................... 15 - 04 - 2009 41........................ 15 - 04 - 2009 10........................ 15 - 04 - 2009 11......................... 15 - 04 - 2009 12........................ 15 - 04 - 2009 13........................ 15 - 04 - 2009 14........................ 15 - 04 - 2009 15........................ 15 - 04 - 2009 16........................ 15 - 04 - 2009 17........................ 15 - 04 - 2009 18........................ 15 - 04 - 2009 19........................ 15 - 04 - 2009 20........................ 15 - 04 - 2009 21........................ 15 - 04 - 2009 22........................ 15 - 04 - 2009 23........................ 15 - 04 - 2009 24........................ 15 - 04 - 2009 25........................ 15 - 04 - 2009 26........................ 15 - 04 - 2009 27........................ 15 - 04 - 2009 28........................ 15 - 04 - 2009 29........................ 15 - 04 - 2009 30........................ 15 - 04 - 2009 31........................ 15 - 04 - 2009 32........................ 15 - 04 - 2009 EFFECTIVITY ALL 71-00-00 page 3 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant Table of Contents. 1. ENGINE COWLING...................................................................................6 8.2. Thrust Reverser Halves Closure..............................................................34 1.1. Inlet Cowl...............................................................................................6 8.3. Thrust Hold-Open Equipment...............................................................36 1.2. Fan Cowls...............................................................................................6 1.3. Thrust Reverser.......................................................................................6 9.ENGINE STORAGE AND PRESERVATION................................................38 9.1 General.................................................................................................38 2. ENGINE HAZARDS...................................................................................8 2.1. Inlet Suction...........................................................................................8 2.2. Exhaust Heat..........................................................................................8 2.3. Exhaust Velocity......................................................................................8 2.4. Engine Noise...........................................................................................8 2.5. Engine Entry/Exit Corridor.....................................................................16 2.6. Training Information Point.....................................................................16 3. ENGINE MOUNTS..................................................................................20 4. ELECTRICAL HARNESSES.......................................................................24 5. ENGINE DRAINS.....................................................................................26 6. ACCESS DOORS.....................................................................................28 6.1. T12 Access/Pressure Relief Door............................................................28 6.2. Oil Tank Access Door.............................................................................28 6.3. IDG Access Door...................................................................................28 6.4. Chip Detector/Pressure Relief Door........................................................28 6.5. T/R Hydraulic Actuator’s Aft Attachment Access Door............................28 6.6. Vortex Control Device...........................................................................28 7. FAN COWLS...........................................................................................30 7.1. Fan Cowl Latches..................................................................................30 7.2. Fan Cowl Hold Open Rods....................................................................30 7.3. Fan Cowl Hinges...................................................................................30 8. THRUST REVERSER HALVES..................................................................32 8.1. Thrust Reverser Halves Opening............................................................32 EFFECTIVITY ALL 71-00-00 page 4 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant List of Illustrations. Abbreviations and Acronyms AND HAND PUMP.................................................................................................................. 35 BSV Burner Staging Valve BREAKAWAY THRUST HAZARD AREA..................................................................................... 10 °C Degrees Celcius DISCONNECTIONS.................................................................................................................. 33 DISCONNECTIONS.................................................................................................................. 36 cm Centimeters ELECTRICAL HARNESSES......................................................................................................... 25 FFCCV Fan Frame Compressor Case Vibration ENGINE COWLING.................................................................................................................. 29 ft Feet ENGINE DRAINS...................................................................................................................... 27 HMU Hydromechanical Unit ENGINE INLET HAZARD AREA................................................................................................. 15 ENGINE INLET HAZARD AREAS............................................................................................... 14 HPTACC High Pressure Turbine Active Clearance Control ENGINE MAINTENANCE ENTRY/EXIT CORRIDORS.................................................................... 17 IDG Integrated Drive Generator ENGINE MAINTENANCE ENTRY/EXIT CORRIDORS.................................................................... 18 in Inches ENGINE MAINTENANCE ENTRY/EXIT CORRIDORS.................................................................... 19 kg Kilograms ENGINE MOUNTS................................................................................................................... 21 ENGINE NOISE HAZARD AREA................................................................................................ 13 lbs Pounds ENGINE PRESERVATION........................................................................................................... 39 m Meters ENGINE PRESERVATION........................................................................................................... 41 RPM Revolution Per Minute FAN COWL............................................................................................................................. 31 TBV Transient Bleed Valve HOLD-OPEN ACTUATOR ........................................................................................................ 33 MIN IDLE POWER ENGINE HAZARD AREA................................................................................. 9 VBV Variable Bleed Valve POWER PLANT INTRODUCTION................................................................................................. 7 VSV Variable Stator Vanes REVERSE BREAKAWAY - POWER HAZARD AREA..................................................................... 12 REVERSE MIN. IDLE POWER HAZARD AREA............................................................................ 12 TAKE-OFF THRUST HAZARD AREA.......................................................................................... 11 THRUST LINK INSTALLATION................................................................................................... 23 THRUST REVERSER ................................................................................................................. 33 THRUST REVERSER ACTUATOR SAFETY LOCK ........................................................................ 35 THRUST REVERSER HOLD-OPEN ACTUATOR............................................................................ 36 THRUST REVERSER HOLD OPEN EQUIPMENT........................................................................... 37 THRUST REVERSER LATCH RELEASE........................................................................................ 33 THRUST REVERSER LATCH RELEASE........................................................................................ 34 EFFECTIVITY ALL 71-00-00 page 5 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 1. ENGINE COWLING. The engine cowling gives an aerodynamically smooth surface into and over the 1.1. Inlet Cowl. engine. It also gives a protective area for engine components and accessories. The inlet cowl sends air into the engine. The inlet cowl attaches to the engine. These are the parts of the engine cowling : 1.2. Fan Cowls. - Inlet cowl, - Fan cowl, The fan cowls give an aerodynamically smooth surface over the fan case. - Thrust reverser. The fan cowls attach to the fan cowl support beam. The fan cowls open for maintenance. 1.3. Thrust Reverser. Each T/R has a left and right half. Each half has a translating sleeve which moves aft (deploy position) for reverse thrust. The two sleeves work independently from each other. The thrust reverser (T/R) system changes the direction of the fan air exhaust to help create reverse thrust. The flight crew uses reverse thrust to slow the airplane after landing or during a rejected takeoff Turbine Exhaust The turbine exhaust system supplies an exit for the engine exhaust gases. This exit increases the velocity of the exhaust gases. This increases engine thrust. The major components of the turbine exhaust system are the exhaust nozzle and the exhaust plug. The turbine exhaust airflow direction does not change during reverse thrust. EFFECTIVITY ALL 71-00-00 page 6 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant STRUT INLET EXHAUST PLUG COWL FAN COWL THRUST REVERSER AND NOZZLE POWER PLANT INTRODUCTION EFFECTIVITY ALL 71-00-00 page 7 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 2. ENGINE HAZARDS. It is dangerous to work around engines. Use the entry/exit corridor when the 2.4. Engine Noise. engine is in operation. Also, stay out of the inlet and exhaust areas when the engine is in operation. Engine noise can cause temporary and permanent loss of your ability to hear. You must wear ear protection when near an engine in operation. These are the hazards around an engine in operation : - Inlet suction, - Exhaust heat, - Exhaust velocity, - Engine noise. 2.1. Inlet Suction. Engine inlet suction, can pull people and large objects into the engine. At idle power, the inlet hazard area is a 13 ft (4.0 m) radius around the inlet. WARNING : IF THE WIND IS OVER 25 KNOTS, INCREASE THE INLET HAZARD AREA BY 20%. 2.2. Exhaust Heat. The engine exhaust is very hot for long distances behind the engine. This can cause damage to personnel and equipment. 2.3. Exhaust Velocity. Exhaust velocity is very high for long distances behind the engine. This can cause damage to personnel and equipment. EFFECTIVITY ALL 71-00-00 page 8 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant MIN IDLE POWER ENGINE HAZARD AREA EFFECTIVITY ALL 71-00-00 page 9 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant BREAKAWAY THRUST HAZARD AREA EFFECTIVITY ALL 71-00-00 page 10 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant TAKE-OFF THRUST HAZARD AREA EFFECTIVITY ALL 71-00-00 page 11 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant REVERSE MIN. IDLE POWER HAZARD AREA REVERSE BREAKAWAY - POWER HAZARD AREA EFFECTIVITY ALL 71-00-00 page 12 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant ENGINE NOISE HAZARD AREA EFFECTIVITY ALL 71-00-00 page 13 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant ENGINE INLET HAZARD AREAS EFFECTIVITY ALL 71-00-00 page 14 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant ENGINE INLET HAZARD AREA EFFECTIVITY ALL 71-00-00 page 15 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 2.5. Engine Entry/Exit Corridor. 2.6. Training Information Point. Engine entry corridors are between the inlet hazard areas and the exhaust Usually, when the engine is in operation, the anticollision lights are on. hazard areas. You should go near an engine in operation only when : - The engine is at idle, - You can speak with people in the flight compartment. For additional safety, wear a safety harness when the engine is in operation. EFFECTIVITY ALL 71-00-00 page 16 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant ENGINE MAINTENANCE ENTRY/EXIT CORRIDORS EFFECTIVITY ALL 71-00-00 page 17 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant ENGINE MAINTENANCE ENTRY/EXIT CORRIDORS EFFECTIVITY ALL 71-00-00 page 18 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant ENGINE MAINTENANCE ENTRY/EXIT CORRIDORS EFFECTIVITY ALL 71-00-00 page 19 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 3. ENGINE MOUNTS. There is a forward and aft engine mount. Each engine mount attaches the engine to the strut. The forward engine mount attaches to the fan frame. The aft engine mount attaches to the turbine frame. EFFECTIVITY ALL 71-00-00 page 20 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant STRUT WING FWD FORWARD ENGINE MOUNT FAN FRAME TURBINE FRAME FWD AFT ENGINE MOUNT ENGINE MOUNTS EFFECTIVITY ALL 71-00-00 page 21 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant Thrust Links. The thrust links bring the thrust of the engine over to the pylon. They attach to the thrust link fittings installed at the rear of the FAN MID BOX structure and the AFT ENGINE MOUNT. EFFECTIVITY ALL 71-00-00 page 22 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant THRUST LINK INSTALLATION EFFECTIVITY ALL 71-00-00 page 23 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 4. ELECTRICAL HARNESSES. The engine electrical harnesses connect at the fan cowl support beam. The electrical harnesses that connect on the right side of the fan cowl support beam come from these components : - Electronic engine control, - N1 speed sensor; - Oil tank (oil quantity transmitter), - Inlet cowl thermal anti-ice valve, - Ignition exciters, - Fan frame compressor case vibration (FFCCV) sensor, - Bleed air regulator, - Ground wing thermal anti-ice solenoid valve, - Overheat/fire detector loop A and B. The electrical harnesses that connect on the left side of the fan cowl support beam come from these components : - Start valve, - N2 speed sensor, - Integrated drive generator (IDG), - Hydraulic system engine-driven pump, - Hydromechanical unit (HMU). EFFECTIVITY ALL 71-00-00 page 24 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant ELECTRICAL HARNESSES EFFECTIVITY ALL 71-00-00 page 25 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 5. ENGINE DRAINS. Engine drains prevent fluid contact with hot engine areas. You use engine drains to detect component failures. Engine drains direct these items overboard : - Oil, - Fuel, - Hydraulic fluid, - Water, - Vapor. These components drain fluids through the starter air, discharge duct in the right fan cowl : - Strut - Main oil/fuel heat exchanger, - Hydromechanical unit (HMU), - Burner staging valve (BSV), - High pressure turbine active clearance control (HPTACC) valve, - Left and right variable stator vane (VSV) actuators, - Left and right variable bleed valve (VBV) actuators, - Transient bleed valve (TBV). Fluids drain through a hole in the left fan cowl panel from these components: - Fuel pump, - Integrated drive generator (IDG), - Hydraulic pump. The oil tank drains fluid through a hole in the right fan cowl panel. EFFECTIVITY ALL 71-00-00 page 26 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant OIL TANK STRUT FUEL PUMP DRAIN PAD FWD HYDRAULIC PUMP STARTER AIR AND IDG DRAIN DISCHARGE DUCT HMU OIL TANK MAIN OIL/FUEL HEAT EXCHANGER STARTER AIR STRUT DISCHARGE DUCT TBV LEFT VBV FUEL PUMP RIGHT VSV LEFT VSV IDG RIGHT VBV HPTCC HYDRAULIC PUMP BSV FWD FWD LEFT FAN COWL PANEL DRAINS RIGHT FAN COWL PANEL DRAINS ENGINE DRAINS EFFECTIVITY ALL 71-11-00 page 27 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 6. ACCESS DOORS. 6.1. T12 Access/Pressure Relief Door. 6.6. Vortex Control Device. The T12 access/pressure relief door is on the inlet cowl. The T12 access/ The vortex control device smooths airflow around the wing. pressure relief door permits access to the T12 sensor. It is also a pressure relief It is on the inboard fan cowl. door. 6.2. Oil Tank Access Door. The oil tank access door permits access to the oil tank for servicing. It is on the right fan cowl. 6.3. IDG Access Door. The IDG access door permits access to the IDG for servicing. It is on the left fan cowl panel. 6.4. Chip Detector/Pressure Relief Door. The chip detector access door permits access to the chip detectors. It also is a pressure relief door. It is on the left fan cowl. 6.5. T/R Hydraulic Actuator’s Aft Attachment Access Door. Each T/R cowl (half) has three access doors. You remove the access doors to get access to the T/R hydraulic actuator’s aft attach point. EFFECTIVITY ALL 71-11-00 page 28 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant IDG ACCESS DOOR CHIP DETECTOR/ PRESSURE RELIEF DOOR VORTEX INLET COWL FAN COWL THRUST REVERSER CONTROL DEVICE T12 ACCESS/ PRESSURE RELIEF DOOR THRUST REVERSER ACTUATOR AFT ATTACHMENT ACCESS DOOR OIL TANK ACCESS DOOR ENGINE COWLING EFFECTIVITY ALL 71-11-00 page 29 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 7. FAN COWLS. There are two fan cowls for each engine. Each fan cowl attaches to the strut 7.1. Fan Cowl Latches. with three hinges. Three fan cowl latches secure the left and right fan cowls together. The fan cowls are made of aluminum. The left fan cowl weighs 80 lbs (36 kg). All latches are along the bottom of the fan cowls. The right fan cowl weighs 96 lbs (44 kgs). 7.2. Fan Cowl Hold Open Rods. Each fan cowl has two fan cowl hold open rods. One end of each hold open rod attaches to the fan cowl. When the cowl is closed, the other end attaches to a receiver on the fan cowl. When the cowl is open, the other end attaches to a receiver on the engine. Each hold open rod is telescopic. Each hold open rod has a collar that locks the hold open rod in place. A yellow lock indication shows when the hold open rod is in the locked position. 7.3. Fan Cowl Hinges. Each fan cowl hinge has these components : - Fan cowl clevis, - Quick release pin, - Strug lug. Each fan cowl clevis is on the fan cowl. All strut lugs are on the strut. The quick release pins make it easy to remove a fan cowl. EFFECTIVITY ALL 71-11-00 page 30 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant FAN COWL (OPEN) COLLAR LOCKED INDICATION RECEIVER (ON ENGINE) FAN COWL FAN COWL CLEVIS LATCH KEEPER QUICK RELEASE PIN FAN COWL LATCH FAN COWL HINGE (3) HOLD OPEN RODS (2) FAN COWL (TYPICAL) EFFECTIVITY ALL 71-11-00 page 31 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 8. THRUST REVERSER HALVES. There are two thrust reverser halves for each engine. Both of them are attached to the strut with hinges. They are very heavy and need an hydraulic actuator to be opened. When open, the installation of the actuator safety lock is required for safety if you have to work under the cowling. 8.1. Thrust Reverser Halves Opening. In order to open the thrust reverser halves, you first have to unlatch the six latches from the rear to the front. Make sure they are completely disengaged and then rise the halve using the handpump. NOTE : In order to open the thrust reverser halves, you first have to open the fan cowl panels. Not only because there is an overlap, but also to gain access to the handpump connections. EFFECTIVITY ALL 71-00-00 page 32 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant THRUST REVERSER HOLD-OPEN ACTUATOR DISCONNECTIONS THRUST REVERSER LATCH RELEASE EFFECTIVITY ALL 71-00-00 page 33 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 8.2. Thrust Reverser Halves Closure. In order to close the T.R. halves, you can apply the same procedure as for the opening, but in the opposite direction. First let drop the T.R. halves, releasing the pressure of the actuator by opening the valve on the handpump. When both halves are down, install the latches from the front to the rear. If the halves are too far from each other, you can use a special tool called “latch lever tool” to pull them closer so that the latch hook can fetch the latch keeper before you latch them, positioning the latch handle in the place. THRUST REVERSER LATCH RELEASE EFFECTIVITY ALL 71-00-00 page 34 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant THRUST REVERSER ACTUATOR SAFETY LOCK AND HAND PUMP EFFECTIVITY ALL 71-00-00 page 35 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 8.3. Thrust Hold-Open Equipment. If the engine has to be removed, you have to install the thrust reverser hold- open equipment in order to keep the T.R. halves open, when you remove the engine. This equipment has to be attached to the bottom of the pylon and, at both ends, two beam assemblies will be adjusted to keep the thrust reverser halves open. After actuator depressurization, you will disconnect the thrust reverser opening actuator at the bottom and store it on the thrust reverser halve structure. More over the thrust reverser system will be explained in chapter 78 : Engine Exhaust. THRUST REVERSER HOLD-OPEN ACTUATOR DISCONNECTIONS EFFECTIVITY ALL 71-00-00 page 36 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant THRUST REVERSER HOLD OPEN EQUIPMENT EFFECTIVITY ALL 71-00-00 page 37 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant 9.ENGINE STORAGE AND PRESERVATION 9.1 General that you can start; a power plant that is not serviceable is one that you cannot start. This section contains instructions for power plant preservation, preservation renewal, and depreservation. - The instructions usually apply to power plants that are installed (on-wing). The different procedures listed below are available. They differ according to the planned time of storage: - Where it is applicable, different instructions are given for engines that are not installed (offwing). - Up to 10 Days Preservation - Up to 10 Days Preservation Renewal - Up to 30 Days Preservation - Up to 30 Days Preservation Renewal Preservation instructions give the recommended procedures as the minimum - Up to 90 Days Preservation steps necessary to prevent unwanted liquid and materials in the power - Up to 90 Days Preservation Renewal plant, corrosion, and atmospheric conditions during times of storage and no - Up to 90 Days Depreservation operation, or landing after an in-flight shutdown. - 30 to 365 Days Preservation - 30 to 365 Days Preservation Renewal If preservation renewal is permitted, it gives the instructions for the renewal of - 30 to 365 Days Depreservation the reservation period. - Long Term Preservation Period (365 Days) Exceeded - Engine Dry-Out Procedure Depreservation instructions consist of steps that put a power plant back to the usual operational condition. Preservation procedures are recommended as an aid to find the necessary precautions that you must do to give sufficient protection to the power plant from the elements during times of storage and no operation. The procedures are different for different lengths of non-operation time, different types of preservation, and if the power plant is serviceable or not - Power plant preservation is a flexible program that you can do in such a way serviceable. which best agrees with the applicable weather and storage conditions. NOTE: For this procedure, the definition of an engine that is serviceable and - More care is necessary for a program for power plants that are not an engine that is not serviceable is as follows: A serviceable power plant is one operational in high humidity or large temperature changes or near a salt water EFFECTIVITY ALL 71-00-00 page 38 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant ENGINE PRESERVATION EFFECTIVITY ALL 71-00-00 page 39 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant area, than for the power plants that are in drier climates or less bad weather conditions. You must do a schedule for the preservation programs for power plants that are not serviceable to do the preservation renewal procedures and monitor the schedule regularly to make sure that you did the necessary procedures before the expiration of preservation time. You must examine the preservation of the power plant as the weather conditions and conditions of power plant protection change and do the procedures necessary to keep the power plant in a serviceable condition. NOTE: You cannot preserve the engines and put them into storage without maintenance. You must do a schedule (for a power plant in revenue service) and then implement it. When you use desiccants you must change them regularly, applicable to environmental conditions, to keep the desiccant with a good protection life. You must pump the variable bleed valves (VBV) closed (75-32-00) when you preserve and store the power plant. This will prevent unwanted material in the core engine inlet through the VBV’s. If you preserve a power plant for more than the long term preservation time (365 days), you must do the power plant operation procedure to make sure the power plant is serviceable before you put the power plant back into service or preserve the engine for a longer time. You must do the engine dry-out procedure when an engine had an in-flight shutdown, and when you preserve an engine that is not serviceable for a long time. Procedures for engines that are removed from the airplane are in the CFMI Engine Shop Manual, Section 72-00-00. EFFECTIVITY ALL 71-00-00 page 40 31 - 08 - 2009 Rev : 2.1 B737NG/71/301 Training manual Powerplant ENGINE PRESERVATION EFFECTIVITY ALL 71-00-00 page 41 31 - 08 - 2009 Rev : 2.1