POWER PLANT - ENGINE MOUNT HEAT SHROUD INSPECTION/REWORK

Transcription

1 Beech TITLE: POWER PLANT - ENGINE MOUNT HEAT SHROUD INSPECTION/REWORK 1. Planning Information A. Effectivity (1) Airplanes Raytheon Aircraft Model A36 Bonanza, Serials E-3471 through E-3508, E-3510, E-3512, and E If you are no longer in possession of the airplane, please forward this information to the present owner. (2) Spares B. Reason None. This Service Bulletin is being issued to inspect the aft (rear) engine mount isolators for the presence of a P/N engine mount (heat) shroud. If the P/N engine mount shroud is installed at the right aft mount fitting location, it may chafe on the cast aluminum RH rear engine mount fitting due to a difference in geometry between the left and right mounts. Such chafing could eventually lead to fracture of the right aft engine mount and further structural damage to the airplane. The P/N engine mount shroud is required only at the left aft engine mount isolator location to protect the engine mount isolator from exhaust system heat degradation. C. Description The aft (rear) engine mount isolators are inspected for correct location of the P/N engine mount (heat) shroud. If a P/N engine mount shroud is installed at the right aft engine mount isolator location, it is removed for possible reinstallation on the LH side. The P/N RH rear engine mount fitting is inspected for damage. If damaged, the RH rear engine mount fitting may be dressed out, if the fitting is within allowable damage limits. Replacement is required only if the P/N 35- The export of these commodities, technology or software are subject to the US Export Administration Regulations. Diversion contrary to U.S. law is prohibited. For guidance on export control requirements, contact the Commerce Department s Bureau of Export Administration at or at Raytheon Aircraft Company (RAC) issues Service Information for the benefit of owners and fixed base operators in the form of two classes of Service Bulletins. The first class, Mandatory Service Bulletins (red border) includes changes, inspections and modifications that could affect safety or crashworthiness. RAC also issues Service Bulletins with no red border which are designated as either recommended or optional in the compliance section within the bulletin. In the case of recommended Service Bulletins, RAC feels the changes, modifications, improvements or inspections will benefit the owner/operator and although highly recommended, Recommended Service Bulletins are not considered mandatory at the time of issuance. In the case of Optional Service Bulletins, compliance with the changes, modifications, improvements or inspections is at the owner/operator s discretion. Both classes are mailed to: (a) RAC Authorized Service Centers. (b) Owners of record on the FAA Aircraft Registration Branch List and the RAC International Owner Notification/Registration Service List. (c) Those having a publications subscription. Information on Owner Notification Service or subscription can be obtained through any RAC Authorized Service Center. As Mandatory Service Bulletins and Service Bulletins are issued, temporary notification in the Service Bulletin Master Index should be made until the index is revised. Warranty will be allowed only when specifically defined in the Service Bulletin and in accordance with the RAC Warranty Policy. Unless otherwise designated, RAC Mandatory Service Bulletins, Service Bulletins and RAC Kits are approved for installation on RAC airplanes in original or RAC modified configurations only. RAC Mandatory Service Bulletins, Service Bulletins and Kits may not be compatible with airplanes modified by STC installations or modifications other than RAC approved kits. 1 of 13

2 RH rear engine mount fitting is damaged beyond allowable limits. Rework is accomplished to install the P/N engine mount shroud if it is missing at the left aft engine mount isolator location. D. Compliance An Airworthiness Directive will be requested on the matter covered by this Service Bulletin. Raytheon Aircraft Company considers this to be a mandatory modification and it must be accomplished at the next scheduled inspection after receipt of this Service Bulletin, but no later than the next 100 flight hours or 12 months, whichever occurs first. E. Approval The engineering data contained in this Service Bulletin is FAA approved. F. Manpower The following information is for planning purposes only: Estimated man-hours for relocation of engine mount shroud to LH side: 3 hours. Estimated man-hours for RH rear engine mount fitting replacement: 6 hours. Estimated man-hours for blend, fluorescent penetrant inspection, and paint rework: 1.5 hours. Suggested number of men: 1 man. The above is an estimate based on experienced, properly equipped personnel complying with this Service Bulletin. Occasionally, after work has started, conditions may be found which could result in additional man-hours. G. Weight and Balance None. H. Electrical Load Data Not changed. I. Software Accomplishment Summary Not applicable. J. References Raytheon Aircraft BEECH BONANZA SERIES Maintenance Manual, P/N A24 or subsequent revision, Chapters and K. Publications Affected It is recommended that a note See Service Bulletin No be made in the following: Raytheon Aircraft BEECH BONANZA Illustrated Parts Catalog, P/N G16 or subsequent revision, Functional Group of 13

3 L. Interchangeability of Parts Not applicable. M. Warranty Credit SERVICE BULLETIN Warranty credit for labor and parts to the extent noted under MANPOWER and MATERIAL will be allowed on all affected airplanes. Warranty coverage offered in this Service Bulletin will expire 12 months from the last day of the month this Service Bulletin is issued. After that date, the owner/operator assumes the responsibility for compliance cost. Raytheon Aircraft Company reserves the right to void warranty coverage in the area affected by this Service Bulletin until the date the Service Bulletin is accomplished by a Raytheon Aircraft Company Authorized Service Center. All warranty work must be accomplished by a Raytheon Aircraft Authorized Service Center rated to perform maintenance on the specific model of Beech Airplane. All warranty reimbursements are handled through Raytheon Aircraft Company Authorized Service Centers. The owner/operator should arrange for an Authorized Service Center to perform the work and the Authorized Service Center must submit the standard Raytheon Aircraft Company warranty claim. 2. Material Information A. Materials - Price and Availability Contact a Raytheon Aircraft Authorized Service Center for information. B. Industry Support Not applicable. C. Airplanes The following parts required for this modification may be ordered through a Raytheon Aircraft Authorized Service Center or RAPID: Part Number Description Quantity Per Airplane Shroud, Engine Mount 1, Fitting, Rear Engine Mount, RH 1, N3 Nut 2, or MS Roll Pin (CRES spring pin, inch diameter, 1.25-inch long) 1, Raytheon Aircraft Company expressly reserves the right to supersede, cancel and/or declare obsolete, without prior notice, any parts or publications that may be referenced in this Service Bulletin. 3 of 13

4 The following materials may be obtained locally: Part Number Description Quantity Per Airplane TT-N-95, Type II Aliphatic Naphtha TT-I-735A or equivalent Isopropyl Alcohol ASTM D329 or equivalent Acetone MIL-DTL in accordance with MIL-C (Alodine 1200, 1200S, or 1201 or equivalent) CCC-C-C-440, A-A-1491 or equivalent Chemical Conversion Coating for Aluminum and Aluminum Alloys Cotton Cheesecloth DOD-R equivalent or Rags Obtain from Barton Solvents, 201 S. Cedar, Valley Center, KS or Eastman Chemical Products, Inc., P.O. Box 431, Kingsport, TN A-A or equivalent or P/N (Obtain from Eastman Kodak Company, 343 State Street, Rochester, NY 14650) MIL-PRF-121, Grade A, Type II, Class 1 or equivalent SAE AMS-T-22085, Type III or equivalent MIL-PRF or (P/N of Pratt & Lambert) or QT (P/N of Sherwin Williams) or equivalent Methyl Propyl Ketone Gloves, Polyethylene, Industrial, Solvent Handling Barrier Material, Grease and Water Proof, Flexible Tape, Pressure Sensitive Adhesive (Masking) Paint, Touchup (Matterhorn White, FED-STD- 595 or equivalent to match existing RH aft engine mount fitting finish) MIL-P Epoxy Polyamide Primer 4 of 13

5 Part Number Description Quantity Per Airplane Blue Twill Medium Grit - #150, Fine Grit - #320, and Extra Fine - #400 Grit or equivalent A-A or Scotchbrite or equivalent Emery Cloth Abrasive Mat or Pad D. Spares Not applicable. E. Reidentified Parts None. F. Tooling - Price and Availability Part Number Description Quantity Per Airplane GGG-C-105 or equivalent Digital Micrometer MIL-I or equivalent Depth Gage, Indicator Dial Zyglo # or equivalent (Obtain from Test Equipment Distributors, Division of X- Ray Industries, Inc., T Piedmont, Troy, MI , Telephone or Newco, Inc., Florence, SC, Telephone ) Fluorescent Penetrant Kit 1, 3. Accomplishment Instructions This Service Bulletin shall be accomplished as follows: NOTE Should any difficulty be encountered in accomplishing this Service Bulletin, contact Raytheon Aircraft Company at or of 13

6 A. Airplane Observe all Warnings and Cautions contained in the aircraft manuals referenced in this Service Bulletin. Whenever any part of this system is dismantled, adjusted, repaired or renewed, detailed investigation must be made on completion to make sure that distortion, tools, rags or any other loose articles or foreign matter that could impede the free movement and safe operation of the system are not present, and that the systems and installations in the work area are clean. INSPECTION OF ENGINE MOUNT SHROUD LOCATION (1) Open the left and right engine cowlings to gain access to the aft engine mounts. (2) Refer to Figure 1 and inspect for presence of a P/N engine mount shroud at the left aft (rear) engine mount isolator location. An engine mount (heat) shroud is required at this location. (3) Refer to Figure 1 and inspect the right aft engine mount isolator location. Verify that a P/N heat shroud is not installed at the right side location. An engine mount shroud is not required and is not to be installed in this location. (4) If inspection reveals that a P/N engine mount shroud is correctly installed in accordance with Figure 1 at the left aft engine mount isolator location and no engine mount shroud is installed at the right aft engine mount isolator location, proceed to steps (22) through (24) for close up. (5) If inspection reveals an incorrect installation, proceed to the following applicable steps to determine the damage scope and disposition. REMOVAL OF RH AFT ENGINE MOUNT SHROUD AND INSPECTION FOR ENGINE MOUNT DAMAGE (6) Remove all power from the airplane and disconnect the battery. Display warning notices prohibiting reconnection of airplane electrical power. Any time the P/N B8 bolt is removed, the bolt removal may affect orientation of one or both of the engine mount isolator halves. Check the engine mount isolator to roll pin alignment for proper orientation (clocking). Spacer and roll pin alignment and proper clocking are critical to proper installation of the engine mount isolators. When properly clocked, the roll pin installed in the P/N engine mount fitting inserts into a matching hole in the P/N J engine isolator mounting kit. Replace the roll pin if it is damaged with a P/N or MS roll pin. (7) Refer to Figure 1 and remove the P/N B8 bolt (right side), that secures the P/N engine mount shroud at the right aft engine mount isolator location. Retain the bolt and washer for reinstallation in step (10). Discard the (nonreusable nylon insert) nut. 6 of 13

7 (8) Remove the P/N engine mount shroud from the right aft engine mount isolator location and retain the shroud for reinstallation at the left aft engine mount location. (9) Inspect the P/N RH rear engine mount fitting for damage. Damage is defined as wear, scratches, gouges, and nicks. Damage may be degradation of the protective corrosion preventive painted finish or the underlying metal and its manufacturer-applied protective treatment. If no damage is present, accomplish step (10), then steps (18) through (24). If damage is greater than 0.10-inch depth, replacement of the RH rear engine mount fitting is required. Proceed to step (11). If damage is 0.10 inch or less in depth, accomplish step (10), skip step (11) and proceed to step (12) for engine mount fitting dress out, cleaning, and touch up and shroud relocation. (10) Using a new P/N N3 nut and retained washer, reinstall the existing P/N B8 bolt retained from step (7) to secure the RH engine isolator mount. Torque to inch-pounds. Refer to Chapter of the airplane Maintenance Manual. REPLACEMENT OF DAMAGED RH AFT ENGINE MOUNT (11) Replace the P/N RH rear engine mount fitting in accordance with the following: Support the engine during RH rear engine mount fitting replacement. Damage to engine and structural components could result. (a) Remove both upper cowling doors. Refer to Chapter of the airplane Maintenance Manual. (b) Use a suitable hoist to secure the engine during RH rear engine mount fitting removal. NOTE Make note of the length and location of each rear engine mount fitting bolt and the number and location of washers to aid in installation of the replacement P/N RH rear engine mount fitting. (c) Remove and retain attaching hardware securing the RH rear engine mount fitting. (d) Remove and discard the damaged RH rear engine mount fitting. (e) Obtain replacement P/N RH rear engine mount fitting and press or drive a new P/N or MS roll pin through the fitting such that the roll pin protrudes equally on both sides of the engine mount fitting. Assemble the top half of the engine mount isolator to the engine mount fitting. Install to airplane structure using attachment hardware retained from removal procedures. Torque to inch-pounds. Refer to Chapter of the airplane Maintenance Manual. Do not cross-thread or force the bolt if it binds. Adjust alignment slightly and retry. Damage to the bolt and engine mount isolator could occur. 7 of 13

8 (f) Using a new P/N N3 nut and retained P/N AN washer, assemble the lower half of the engine mount isolator to the engine mount fitting, then install P/N B8 bolt at the right aft engine mount isolator location to secure the engine mount. Torque to inch-pounds. Refer to Chapter of the airplane Maintenance Manual. NOTE At the installer s option, it may be desirable to wait until all required installation operations are complete before removing the hoist and installing upper cowling doors. (g) Remove the hoist and install upper cowling doors. Refer to Chapter of the airplane Maintenance Manual. (h) Skip steps (12) through (17), and proceed to steps (18) through (24). REPAIR OF DAMAGE TO RH AFT ENGINE MOUNT (12) Accomplish dress out, cleaning, and touch up of the P/N RH rear engine mount fitting in accordance with the following: (a) Use progressively finer emery cloth to remove damage (wear, scratches, gouges, and nicks) up to a depth of 0.10 inch. Maintain a blend ratio or dress out ratio of 10:1 for parts with damage less than 0.10 inch depth. Do not remove any more material than necessary to remove all damage. Refer to locally obtained materials section of MATERIAL INFORMATION for abrasive material information. Solvents are flammable and hazardous. Avoid contact with skin, eyes, and respiratory tract. Skin and eye protection is required. Avoid repeated or prolonged contact. Keep away from flames or sources of heat. Use in a wellventilated area. (b) Wipe up sanding debris with clean rags or CCC-C-440 clean cotton cheesecloth moistened with a suitable solvent (TT-N-95, Type II aliphatic naphtha, ASTM D239 acetone, TT-I-735A isopropyl alcohol, or methyl propyl ketone). All personnel performing the Fluorescent Penetrant Inspection must be certified Nondestructive Test Personnel that have obtained applicable training on the equipment and method being used. (c) Perform a final cleaning prior to Fluorescent Penetrant Inspection in accordance with the following: 8 of 13

9 Solvents are flammable and hazardous. Avoid contact with skin, eyes, and respiratory tract. Skin and eye protection is required. Avoid repeated or prolonged contact. Keep away from flames or sources of heat. Use in a wellventilated area. (i) Clean the inspection area with suitable solvent (TT-N-95, Type II aliphatic naphtha, ASTM D239 acetone, TT-I-735A isopropyl alcohol, or methyl propyl ketone) and CCC-C-440 clean cotton cheesecloth to remove grime, oily films, and other contaminants. Use nonmetallic, non-woven A-A (Scotchbrite or equivalent) abrasive pads and TT-N- 95, Type II aliphatic naphtha or equivalent solvent to remove tough foreign contaminants such as grease, oil, water-based grime, mud, etc. Wipe the surface dry with clean cotton cheesecloth. Repeat cleaning procedures until a waterbreak-free surface is achieved. NOTE Many Class 2 solvent removers will not rapidly evaporate at room temperature. Make sure no residual solvent is on the fitting surface prior to application of penetrant. This can be accomplished by thoroughly drying the surface with clean cotton cheesecloth or clean rags, alternately using a more volatile solvent such as isopropyl alcohol to remove the less volatile solvent remover. (d) Perform a Fluorescent Penetrant Inspection of the P/N RH rear engine mount fitting for cracks in accordance with procedures specified in Part Number Zyglo Fluorescent Penetrant Inspection Kit or equivalent. (e) If cracks are still present, repeat steps (12)(a) through (12)(d) as many times as necessary until the cracks are removed without exceeding damage limits. Recheck for cracks using Fluorescent Penetrant Inspection methods in accordance with step (12) (d). If cracks cannot be removed without exceeding the damage limits of step (9), then replace the damaged engine mount in accordance with step (11). (13) Accomplish masking and final cleaning procedures in preparation for touchup painting, in accordance with the following: Use care to protect adjacent areas and avoid dripping or overspray onto surrounding engine surfaces and adjacent components. If required, protect work areas from drips or overspray. (a) Mask off the rework area using MIL-PRF-121 barrier material and SAE AMS-T masking tape. 9 of 13

10 Solvents are flammable and toxic to skin, eyes, and respiratory tract. Avoid eye and repeated skin contact. Use in a well-ventilated area. Keep away from sparks and flames. (b) Clean the rework area with suitable solvent (TT-N-95, Type II aliphatic naphtha, ASTM D239 acetone, TT-I-735A isopropyl alcohol, or methyl propyl ketone) and CCC-C-440 clean cotton cheesecloth to remove grime, oily films, and other contaminants. Use nonmetallic, non-woven A-A (Scotchbrite or equivalent) abrasive pads and TT-N-95, Type II aliphatic naphtha or equivalent solvent to remove tough foreign contaminants such as grease, oil, water-based grime, mud, etc. Wipe the surface dry with clean cotton cheesecloth. Repeat cleaning procedures until a waterbreak-free surface is achieved. Chemical conversion coating (Alodine) may affect skin, eyes, and respiratory tract. Chemical goggles and neoprene gloves should be worn. Use in a well-ventilated area. (c) Apply Alodine 1200, 1200S, or 1201 (MIL-DTL in accordance with MIL-C-5541) Chemical Conversion Coating to the dressed out areas that were reworked (bare metal surfaces). Allow the Alodine to dwell for approximately five minutes. After the dwell time has elapsed, wash the treated area with water, and blot away water with clean cotton cheesecloth or blow dry (do not wipe dry). Many paints, primers, and top coatings are flammable and toxic to skin, eyes and respiratory tract. Eye, skin, and respiratory protection is required. (d) After Alodine 1200, 1200S, or 1201 (MIL-DTL in accordance with MIL-C-5541) Chemical Conversion Coating has dried, apply a coat of MIL-P Epoxy Polyamide Primer or equivalent primer to the rework area. Allow adequate drying time. (14) Accomplish touchup painting procedures, applying Matterhorn White touchup paint (FED-STD-595 or equivalent) over the primer coat to match existing top coat paint. (15) Allow adequate paint drying time. Drying time is normally at least 24 hours under normal temperature conditions. As an alternate method, use a blow dryer to force air dry the area for 1.5 hours at 125 degrees Fahrenheit. (16) Remove barrier material and masking tape. (17) Clean up around the paint touchup area. INSTALLATION OF LH AFT ENGINE MOUNT SHROUD (18) If the inspection of step (2) found the engine mount shroud missing from the left aft engine mount isolator, refer to Figure 1 and remove existing P/N B8 bolt at the left aft engine mount isolator location. 10 of 13

11 Damage to the rear engine mount fitting (casting) in the form of wear, scratches, gouges, and nicks could result if proper clearance is not maintained. (19) Install the P/N engine mount shroud at the left aft location with the flange end up as shown in Figure 1. Use existing P/N B8 bolt, P/N AN washer, and new P/N N3 nut mounting hardware. Torque to inch-pounds. Refer to Chapter of the airplane Maintenance Manual. (20) Check for and ensure clearance exists between the P/N engine mount shroud and the P/N LH rear engine mount fitting.proceed to steps (21) through (24) for close-up operations to return the airplane to service. RETURN TO SERVICE (21) Reconnect the airplane battery, remove warning notices and restore power. (22) Ensure all work areas are clean and clear of tools and miscellaneous items of equipment. (23) Close the left and right engine cowlings that were opened to gain access to the aft engine mounts. (24) Return airplane to service. B. Spares Not applicable. C. Record of Compliance Upon completion of this Service Bulletin, make an appropriate maintenance record entry. 11 of 13

12 SERVICE BULLETIN Engine Mount Shroud Installation Figure 1 12 of 13

13 RH Engine Mount Shroud Removal and RH Rear Engine Mount Fitting Inspection Figure 2 13 of 13