S 643-058
(2)
Lubrizol 1395 and methyl oleate are heavy duty lubricants. They are added to the fluid to reduce the wear on the parts of the shock strut that move.
S 643-059
(3)
Use BMS 3-32, Type I to fill the shock strut for the first time when new, or after overhaul. There is a corrosion inhibitor in the MIL-H-6083 fluid.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
12-15-02
ALL ú ú 01 Page 301 ú May 28/02
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
757 MAINTENANCE MANUAL
S 643-060
(4)
Use BMS 3-32, Type I or Type II at the operator's discretion, for subsequent refills or to top off the strut. These two types of fluid are compatible.
S 643-061
(5)
If the proper mixture is not available, You can use MIL-H-6083 or MIL-H-5606 fluid without additives to top off the strut. Try not to do this, however, because the additive that is already in the strut will become more diluted. This will make it less effective.
S 643-062
(6)
It is not necessary to change the seals in the shock strut if you drained the strut and filled with one of the other fluids.
S 643-063
(7)
Use the premixed fluid, BMS 3-32 Type I and Type II, if it is possible. This is more convenient for the operator and will remove the possiblility of error that can occur when the operator mixes the fluids.
S 643-064
(8)
Qualified vendors and vendor codes for the shock strut fluids are listed in AMM 20-30-04/201.
C. Preferred (Pre-mixed) Shock Strut Fluids
S 643-065
(1)
BMS 3-32, Type I -This is MIL-H-6083 fluid pre-mixed with 1.5 percent by volume of Lubrizol 1395 and 1 percent by volume of methyl oleate.
S 643-066
(2)
BMS 3-32, Type II -This is MIL-H-5606 fluid pre-mixed with 1.5 percent by volume of Lubrizol 1395 and 1 percent by volume of methyl oleate.
D. Optional (Not Pre-mixed) Shock Strut Fluids
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
12-15-02
ALL ú ú 01 Page 302 ú Jan 28/02
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
757 MAINTENANCE MANUAL
S 643-067
CAUTION: YOU MUST MIX SHOCK STRUT FLUIDS THAT ARE NOT PRE-MIXED BEFORE
_______ YOU FILL THE STRUT. IF YOU POUR UNDILUTED LUBRIZOL DIRECTLY INTO A STRUT IT CAN SETTLE TO THE BOTTOM AND NOT MIX CORRECTLY. UNDILUTED LUBRIZOL CAN ALSO CAUSE THE STRUT SEALS TO SWELL AND SOFTEN.
CAUTION: YOU MUST MIX 1 PART LUBRIZOL 1395 WITH 10 PARTS MIL-H-6083 OR
_______ MIL-H-5606 TO DILUTE THE LUBRIZOL BEFORE YOU ADD IT TO THE STRUT. IF YOU DO NOT DILUTE LUBRIZOL BEFORE YOU ADD IT TO THE STRUT IT CAN CAUSE DAMAGE TO THE STRUT AND SEALS.
(1) MIL-H-6083 fluid plus 2.4 percent by volume of Lubrizol 1395 -This mixture can be made from any approved source for MIL-H-6083 and mixed with 2.4 percent by volume of Lubrizol 1395.
NOTE: Operators can choose to add 1.5 percent by volume of Lubrizol
____ 1395 and 1 percent by volume of methyl oleate instead of 2.4 percent by volume of Lubrizol 1395.
S 643-068
(2) MIL-H-5606 fluid plus 2.4 percent by volume of Lubrizol 1395 -This mixture can be made from any approved source for MIL-H-5606 and mixed with 2.4 percent by volume of Lubrizol 1395.
NOTE: Operators can choose to add 1.5 percent by volume of Lubrizol
____ 1395 and 1 percent by volume of methyl oleate instead of 2.4 percent by volume of Lubrizol 1395.
TASK 12-15-02-613-054
3. Examine the Fluid Level of the Shock Strut
__________________________________________
A. General
(1)
This procedure supplies instructions to check the level of the hydraulic fluid in the shock strut of the nose landing gear.
(2)
To do a check of the fluid level, you must measure the pressure and the extension of the shock strut twice, at two different shock strut extensions. The greater the difference between the shock strut extensions, the more accurate the fluid measurement will be.
(a) You can obtain the different shock strut extensions one of two ways: 1) You can take the shock strut measurements at two different
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：757 AMM 飞机维护手册 SERVICING 1(51)
