S E R V I C E B U L L E T I N

Transcription

1 VALVE ASSEMBLY. RESERVOIR VENT P/N 1. Planning Information A. Effectivity This service bulletin is applicable to the following Valve Assembly Essex P/N (Boeing P/N) Serial No. Application (S271N301-2) All B737 B. Reason This change is intended to modify the existing valve to allow for equal pressurization (balancing) of the 737 aircraft hydraulic reservoirs. The modified valve must only be used on aircraft equipped for hydraulic reservoir pressurization balancing, either in production or by incorporation of Boeing Service Bulletin C. Description This service bulletin provides detail information to modify the Reservoir Vent Valve Assembly as follows by replacement of the Inlet Fitting. (Existing) (Modified) Essex P/N (Boeing P/N) Essex P/N (Boeing P/N) (S271N301-2) (S271N301-3) The existing and modified valve are not interchangeable. Page 1 of 8

2 VALVE ASSEMBLY. RESERVOIR VENT P/N D. Approval This service bulletin has been reviewed by the Federal Aviation Administration (FAA) and the repairs and modification herein comply with the applicable Federal Aviation Regulations (FARs) and are FAA approved for installation in the Boeing Model 737 aircraft. E. Manpower An estimated man power of one hour is required to accomplish this service bulletin. F. Material-Cost and Availability The replacement parts required for this modification which are tabulated in Section 3 may be procured from Essex Industries, Inc at the estimated price indicated in Section 3, and will be available 90 days after receipt of order after September All orders for the replacement parts must specify part number and quantities required. The price is subject to change after June 1994 without notice. G. Tooling-Price and Availability No special tools are required. H. Weight and Balance None. I. Electrical Load Data Page 2 of 8

3 VALVE ASSEMBLY. RESERVOIR VENT P/N Not affected. J. Reference The sources of information used in the performance of this service bulletin include Essex engineering documentation and the applicable Component Maintenance Manual. Part No Component Maintenance Manual K. Other Publications Affected CMM will be replaced by a new document (NO ) to reflect this change for the new part number. 2. Service Instructions A. Refer to the manual listed in Section 1.J for applicable disassembly, cleaning, inspection, reassembly and testing instructions. B. Disassembly (Refer to Figure 1) (1) Remove the fitting assembly (60) and gasket (55) and discard both. (2) Record the manufacturing date and serial number from the nameplate (25) to provide reidentification on the new nameplate. Note the direction of the arrow for use in paragraph C.4. Remove the nameplate (25) using a sharp knife or small screw driver. Page 3 of 8

4 VALVE ASSEMBLY. RESERVOIR VENT P/N C. Assembly (Refer to Figure 1) (1) Install a new gasket (55) onto a new fitting (60) and apply one drop of Loctite Grade A to the small threads. Install the fitting into the body (5) through the cover (50). NOTE: The cover (50) must fit inside the scraper (35) and retain the spring (45) and two washers (40) in the order shown in Figure 1. (2) Torque the fitting (60) to the body (5) to \- 10 in-lb. (3) Transfer the recorded nameplate information from paragraph B.2 to the new nameplate (25) by metal stamping. (4) Install the new nameplate (25) in the same location and orientation as the old nameplate. Insert the tab on the nameplate through the bottom of the slot on the nameplate and fold tab over 180 o. D. Testing after Reassembly (1)Attach a pressure tight cap to the large fitting end of the Reservoir Vent Valve. (2) Apply 50 PSIG air pressure to the small fitting end. (3) Apply "Snoop" or other similar leak detector to the interface between the fitting (60) and cover (50). No leakage is allowed. (4) Apply "Snoop" or similar leak detector to the annular space between the slider (30) and cover (50). No leakage is allowed. E. Instruction of Identification Page 4 of 8

5 VALVE ASSEMBLY. RESERVOIR VENT P/N Upon completion of this modification, the Reservoir Vent Valve will be re-identified with the new nameplate as follows: (1) The old part number is removed with the old nameplate and the new part number is applied with the new nameplate. (Old) (New) Boeing P/N MFRS P/N BOEING P/N MFRS P/N S271N301-2 S271N (2) The original date of manufacture and serial number are transferred from the original nameplate to the new nameplate by steel stamping. Page 5 of 8

6 VALVE ASSEMBLY. RESERVOIR VENT P/N 3. Material Information A. The following new parts for the Modification Kit as noted are required to accomplish the modification. (1) Modification Kit Unit List Instructions- New P/N Qty Price Key word Old P/N Disposition K1-1 1 $ MODIFICATION KIT (CONSISTS OF THE Following) FITTING B1-1 A GASKET B NAMEPLATE A Disposition Cord A Disposition Cord B Replace parts as specified in this bulletin. Discard removed/used parts. replace with like part. NOTE : Refer to Figure 1 for item location and part number identification. B. The following assembly materials as noted are required to accomplish the modification. SEALANT... LOCTITE GRADE A LEAK DETECTOR... SNOOP OR EQUIVALENT Page 6 of 8

7 VALVE ASSEMBLY. RESERVOIR VENT P/N Figure 1 - Exploded View Page 7 of 8

8 FILE : SP srp Essex Industries, Inc. VALVE ASSEMBLY. RESERVOIR VENT P/N FIG. OLD NEW ITEM PART NO. PART NO. NOMENCLATURE BODY 10 NAS NAS O-RING 15 NAS NAS O-RING 20 S S GLYD-RING NAMEPLATE SLIDER ASSEMBLY 35 MS MS SCRAPER WASHER SPRING COVER GASKET B FITTING Page 8 of 8