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(4) Battery Compartments. Some support equipment and general purpose test equipment contain internal batteries. Clean, neutralize, and preserve the battery compartment as follows:
(a) Clean and neutralize electrolyte spills in accordance with subparagraphs 602d(1) through (6).
(b) Inspect, clean, treat, and paint the battery compartment in accordance with Chapter 5, subparagraphs 504a through 504f.
(c) When painting of the battery compartment is not practical, temporarily preserve the area in accordance with subparagraph 602e(4).
(5) Meters. Voltmeters, ammeters, and multimeters are usually constructed of high-impact plastic or acrylic. Normally these meters are not disassembled for cleaning. Clean the exterior surfaces as follows:
(a) Clean metal hardware and metal surfaces with cotton swabs and a clean cloth or cheesecloth dampened with Isopropyl Alcohol, TT-I-735. Allow the surface to air dry.
(b) Apply a coating of Water-Displacing Corrosion Preventive Compound, conforming to MIL-DTL-85054, on metal hardware. Take the necessary steps to avoid getting preservative on acrylic plastic face plates.
(c) Clean toggle, rotary, and push-button switches in accordance with subparagraph 603g.
(d) Clean meter face plates in accordance with subparagraph 602g(9).
(e) Clean high-impact plastic or acrylic housings with a 1 ounce solution of nonionic liquid detergent, conforming to MIL-D-16791, Type I, in 1 gallon of water. Clean the surface with a clean cloth or cheesecloth wet with the detergent solution. When the surface is clean, remove the detergent solution by wiping the surface with a clean cloth or cheesecloth that has been dampened with clean water. Rinse the cloth frequently.
(6) Operator and Instrument Panels. Support equipment, general purpose test equipment, and ATE operator instrument panels should be inspected, cleaned, treated, painted, and preserved as follows:
(a) Visually inspect operator and instrument panels for corrosion and contaminants.
Pay particular attention to switches, dials, knobs, and hardware.
(b) Remove corrosion using an abrasive nylon mat, conforming to A-A-58054, Type I.
(c) Clean metal surfaces with cotton swabs and a clean cloth or cheesecloth dampened with Isopropyl Alcohol, TT-I-735. Allow the surface to air dry.
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(d) Apply a coating of Water-Displacing Corrosion Preventive Compound, conforming to MIL-DTL-85054, on metal hardware. Take the necessary steps to avoid getting preservative on acrylic plastic face plates.
(e) Treat and paint operator and instrument panels in accordance with Chapter 5, subparagraphs 504a through f.
(f) Clean toggle, rotary, and push-button switches in accordance with subparagraph 603g.
(g) Clean meter face plates in accordance with subparagraph 602g(9).
(h) Clean and treat light bulb assemblies in accordance with subparagraph 603e.
(7) Internal Cleaning of Support Equipment. With the exception of emergency procedures described in Chapter 10, the internal cleaning of support equipment is normally a function of a repair activity or the OEM. The recommended cleaning and preservation techniques for support equipment are as follows:
(a) Remove covers and housing.
(b) Inspect for oil, grease, hydraulic fluids, and corrosion. Additionally, inspect for components that can act as water and solvent traps. Chapter 4, Table 4-3, lists components that may pose a problem with water and solvent entrapment.
(c) Seal, bag, or remove potential components that may entrap water and solvent.
Chapter 4, subparagraph 405f, describes sealing methods.
(d) Remove oil, grease, and hydraulic fluids using a solvent ultrasonic cleaner. See the ultrasonic cleaning instructions in Chapter 4, subparagraph 404d, and Table 4-2. Solvent ultrasonic clean for 15 seconds and solvent dry for 3 minutes.
(e) Remove corrosion with a mini-abrasive cleaning tool in an approved cleaning booth using technical grade sodium bicarbonate (see Chapter 4, subparagraph 404e).
(f) If no corrosion, oils, greases, or hydraulic fluid were noted in the inspection, clean the internal areas of the support equipment with a water detergent solution as described in Chapter 4, subparagraph 404b.
(g) Treat and paint internal areas of the support equipment in accordance with Chapter 5, subparagraphs 504a through f.
(h) On areas that are not painted but require preservation, apply a thin coat of Water-Displacing Corrosion Preventive Compound, conforming to MIL-PRF-81309, Type III.
Take necessary steps to avoid getting preservative on components that should not be preserved.
(See Chapter 4, subparagraphs 407d and 407e, and Table 4-4.)
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(8) Internal Cleaning of General Purpose Test Equipment. Oscilloscopes, signal generators, frequency counters, etc., usually accumulate more dust and dirt than other contaminants. Internal cleaning and preservation of general purpose test equipment should be accomplished as follows:
(a) Remove covers and housing.
(b) Inspect for oils, grease, dust, dirt, and corrosion. Additionally, inspect for components that can act as water and solvent traps. Chapter 4, Table 4-3, lists components that may pose a problem with water and solvent entrapment.
(c) Seal, bag, or remove potential components that may entrap water and solvent.
Chapter 4, subparagraph 405f, describes sealing methods.
(d) Use a vacuum cleaner to remove loose dust, dirt, and lint from the internal chassis and circuit components.
(e) Remove corrosion with a mini-abrasive cleaning tool in an approved cleaning booth using technical grade sodium bicarbonate (see Chapter 4, subparagraph 404e).
(f) If no corrosion, oils, or greases were noted in the inspection, clean the internal areas of the general purpose test equipment with a water detergent solution as described in Chapter 4, subparagraph 404b.
(g) Treat and paint internal areas of the support equipment in accordance with Chapter 5, subparagraphs 504a through f.
(h) On areas that are not painted but require preservation, apply a thin coat of Water-Displacing Corrosion Preventive Compound, conforming to MIL-PRF-81309, Type III.
Take necessary steps to avoid getting preservative on components that should not be preserved.
(See Chapter 4, subparagraphs 407d and 407e, and Table 4-4.)
(9) Internal Cleaning of ATE. ATE is usually constructed so that circuits are installed in drawers or cabinet-type racks. Attempting to clean the entire drawer or cabinet could prove difficult because of the size and weight of the assembly. Where the assemblies can be moved and mechanically cleaned, use the procedures of subparagraph 603b(8). Those assemblies that cannot be moved and mechanically cleaned should be cleaned and preserved as follows:
(a) Open cabinet doors, remove the cover, and slide drawers to the fully extended position.
(b) Inspect for oil, grease, dust, dirt, and corrosion. Additionally, inspect for components that can act as water and solvent traps. Chapter 4, Table 4-3, lists components that may pose a problem with water and solvent entrapment.
(c) Seal, bag, or remove potential components that may entrap water and solvent.
Chapter 4, subparagraph 405f, describes sealing methods.
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(d) Use a vacuum cleaner to remove loose dust, dirt, and lint from the internal chassis, wiring, and circuit components. Avoid direct contact between the vacuum cleaner hose wand and any delicate circuit components.
(e) Hand clean in accordance with Chapter 4, subparagraph 405g, using a water detergent solution as described in subparagraph 404b(5), or Isopropyl Alcohol, TT-I-735.
CAUTION: If wire wrap circuit board construction is used in ATE, do not apply water detergent solutions or solvents. In wire wrap installations only vacuuming of dirt, dust, and lint is authorized. Do not apply preservation materials to wire wrap circuit boards.
(f) On areas that are not painted but require preservation, apply a thin coat of Water-Displacing Corrosion Preventive Compound, conforming to MIL-PRF-81309, Type III.
Take necessary steps to avoid getting preservative on components that should not be preserved (see Chapter 4, subparagraphs 407d and 407e, Table 4-4, and the caution statement for the preceding, subparagraph 603b(9)(e)).
(10) Internal Cleaning of Microwave Test Equipment. Microwave equipment contains many potential water and solvent entrapment areas. In addition, microwave equipment makes use of many acrylic vanes and lenses in wave guides and cavities, variable attenuators, etc. Generally, these components can be sealed or removed from the chassis prior to cleaning and drying. Internal cleaning and preservation of microwave test equipment should be performed as follows:
(a) Clean the external surface in accordance with subparagraph 603c.
(b) Clean the internal surface in accordance with subparagraph 603c.
(c) Inspect the wave guide for corrosion.
(d) Remove corrosion from external surfaces using an abrasive nylon mat, conforming to A-A-58054, Type I. Wipe off residue with a clean cloth or cheesecloth. Do not disturb the center connector with a cleaning tool or brush.
(e) Clean connector sections by spraying internal and external areas with Isopropyl Alcohol, TT-I-735. Do not disturb the center connector with a cleaning tool or brush. Wipe excess solvent dry with a clean cloth. Allow the section to air dry.
(f) If the wave guide will not be installed immediately, seal the ends of the section with OEM protective caps or pressure-sensitive tape, conforming to MIL-T-22085.
(g) Preserve external areas of the wave guide section with a thin coat of Corrosion Preventive Compound, conforming to MIL-DTL-85054.
CAUTION: Do not apply preservative materials to internal surfaces or areas of wave guide sections or angled physical contact (APC) connectors.
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(11) Special Cleaning Procedures. The following test equipment circuit components should be cleaned, lubricated, and preserved as follows:
(a) Bonding and Grounding Straps. Clean and preserve electrical bonding and grounding straps in accordance with Chapter 7, paragraph 702.
(b) Relays and Circuit Breakers. Clean and preserve relays and circuit breakers in accordance with subparagraph 603f.
(c) Rotary Switches, Trim Potentiometers, and Sliding Cam Switches. Clean, lubricate, and preserve rotary switches, trim potentiometers, and sliding cam switches in accordance with subparagraph 603g, and as follows:
1. Apply Spray Cleaning and Lubricating Compound, conforming to MIL-PRF-29608, Type I, to the internal portion of the switch.
CAUTION: Do not apply Spray Cleaning and Lubricating Compound, MIL-PRF-29608, to printed circuit boards (PCB) or other areas where soldering may be required. This material contains silicone which is difficult to remove and prevents proper adhesion of any material applied to the sprayed area.
2. While the surface is still wet, wipe sliding contacts, cams, and contact points with a clean cotton swab or pipe cleaner as required, to remove dirt, dust, and other residue.
3. Spray cleaned areas that require lubrication with Spray Cleaning and Lubricating Compound, conforming to MIL-PRF-29608, Type I. A silicone lubricant residue will remain. Do not apply preservative materials.
(d) Microminiature PCBs. Clean microminiature PCBs as follows:
1. Hand clean microminiature PCBs of dirt, dust, and other residue with a clean cotton swab or a soft bristle brush wet with Isopropyl Alcohol, TT-I-735, in accordance with Chapter 4, subparagraph 405g.
2. Rinse the microminiature PCBs with deionized water.
3. Dry the microminiature PCBs in accordance with Chapter 4, subparagraph 406e.
(e) Multipin Electrical Connectors and PCB Edge Connectors. Clean, treat, and preserve multipin electrical connectors and PCB edge connectors in accordance with subparagraph 603h, and subparagraphs 603k(1) through (4).
(f) Sliding Attenuators, Variable Attenuators, and Tunable Cavities. Clean, treat, and preserve as follows:
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1. Remove corrosion and tarnish by lightly rubbing with Magic Rub Plastic or a wooden pencil eraser. Care should be taken not to remove the thin plating on the surface.
2. Clean the area by applying Isopropyl Alcohol, TT-I-735, with an acid brush. Rinse the area with Isopropyl Alcohol, TT-I-735, and wipe dry with a clean cloth or cheesecloth. Allow the component to air dry.
CAUTION: Sliding and variable attenuators and tunable cavities are natural water and solvent traps. Do not leave these components exposed during internal equipment cleaning. Clean the exterior of sliding and variable attenuators and tunable cavities by hand where the cleaning solution, rinse water, or solvent can be properly dried.
3. Lubricate sliding components with an application of Spray Cleaning and Lubricating Compound, conforming to MIL-PRF-29608, Type I. Mask any nearby areas where the presence of the silicone lubricant is not desired. Silicone is very difficult to remove and prevents proper adhesion of any material applied to the sprayed area (use Chapter 4, subparagraph 405j).
4. Spray a thin coating of Water-Displacing Corrosion Preventive Compound, conforming to MIL-PRF-81309, Type III, on external metal surfaces. Avoid placing preservative material on sliding components.
(g) Internal Surfaces of Sliding Attenuators, Variable Attenuators, and Tunable Cavities. Clean internal surfaces of sliding attenuators, variable attenuators, and tunable cavities as follows:
1. Hand clean the slide area(s) by applying Isopropyl Alcohol, TT-I-735, with an acid brush.
CAUTION: Sliding and variable attenuators and tunable cavities are natural water and solvent traps. Do not leave these components exposed during internal equipment cleaning. Clean the interior surfaces of sliding and variable attenuators and tunable cavities by hand only where the cleaning solution, rinse water, or solvent can be properly dried. Do not apply preservative material to internal slide surfaces.
2. Rinse the area with Isopropyl Alcohol, TT-I-735, and wipe dry with a clean cloth or cheesecloth. Allow the component to air dry.
(12) Painting Systems. It is important that the metallic housings of avionics test equipment be protected from the environment. A properly applied paint system provides effective long-term protection. These paint systems can be degraded by abrasion, chipping, scratching, and other forms of in-service damage. When damage to the paint finish occurs, immediate action should be taken to restore protection to the base metal. Restore corrosion protection as follows:
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(a) Temporary Protection.
1. Clean the bare area with a clean cloth or cheesecloth dampened with Isopropyl Alcohol, TT-I-735. Allow the surface to air dry.
2. Spray a thin coating of Corrosion Preventive Compound, MIL-DTL-85054, to the clean, bare area.
(b) Paint Finish Restoration. Inspect, clean, treat, and apply protective paint finish in accordance with subparagraph 602b. The paint color selection should be in accordance with the OEM’s maintenance instructions.
NOTE: Paint color matching is a difficult process. Paint from the same manufacturer, color number, and batch number will not match the same paint applied earlier that has been allowed to age and weather.
(13) Packaging, Handling, and Storage. The packaging, handling, and storage procedures of Chapter 4, paragraph 409, should apply to test equipment. The following additional requirements should also apply.
(a) Wipe down test equipment on a regular basis using a clean, dry, soft cloth. This will prevent accumulation of soils and potentially corrosive materials on the equipment.
Additionally, clean equipment generally receives better handling treatment from the user.
(b) Ensure all appropriate caps are installed on equipment cavities and connections.
(c) Ensure all decals, calibration stickers, part numbers, and serial numbers are kept legible and up to date.
(d) Test equipment should be stored and shipped in the appropriate carrying case in accordance with Chapter 4, subparagraph 409d.
c. Wave Guides. Wave guides are only effective if the internal surfaces are clean and free of damage (dents) and corrosion (surface or pitting). Wave guide mounting and flange seal integrity must be maintained; otherwise, the electrical characteristic of the wave guide will be adversely affected. Currently, there is no method of preserving the internal surface of the wave guide except by plating another metal, such as gold or silver, during the manufacture of the wave guide. This plating process is expensive. Wave guides used in aircraft are generally not plated.
The method of protecting the internal finish on a wave guide is to prevent moisture intrusion.
Moisture intrusion can occur any time the wave guide seal is broken and opened for maintenance. Wave guides that must be opened should be sealed at the flanged ends with an appropriate cap or pressure-sensitive tape. Prior to assembly, all residue from the pressure-sensitive tape should be removed. The following describes methods for cleaning, removing corrosion, and preserving external wave guide surfaces.
(1) Ensure the ends of the wave guide are sealed using an appropriate cap or pressure-sensitive tape.
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(2) Visually inspect the wave guide for evidence of corrosion.
NOTE: Wave guides are normally replaced if there is evidence of corrosion, either internally or on the mating surfaces.
(3) Remove corrosion on the exterior of wave guides using an abrasive nylon mat, conforming to A-A-58054, Type I.
(4) Remove protective caps or pressure-sensitive tape from mating flange surfaces.
(5) Wipe clean exterior surfaces and mating flange surfaces with a clean cloth or cheesecloth dampened with Isopropyl Alcohol, TT-I-735. Allow the surfaces to air dry.
(6) If the wave guide is not going to be installed immediately, install protective caps or apply pressure-sensitive tape to mating flange surfaces.
(7) If the wave guide is to be installed, connect in accordance with the OEM’s maintenance instructions.
(8) Preserve wave guides as follows:
(a) For wave guides that are not to be installed, spray a thin coating of Corrosion Preventive Compound, MIL-DTL-85054, on the exterior surfaces.
(b) For wave guides that will be installed, spray a thin coating of Corrosion Preventive Compound, MIL-DTL-85054, on the exterior surfaces and hardware after installation.
d. Wave Guide Feed Horns. Wave guide feed horns attached to some antenna dishes are subject to corrosive attack at the open end of the wave guide. To protect this open end area from corrosion, clean and preserve as follows:
(1) Wipe feed horn surfaces with a clean cloth or cheesecloth dampened with Isopropyl Alcohol, TT-I-735. Allow the surfaces to air dry.
(2) Spray the inner and outer throat area of the wave guide opening with an ultra-thin coat of Water-Displacing Corrosion Preventive Compound, conforming to MIL-PRF-81309, Type III. Apply to exterior surfaces of the feed horn. For interior surfaces, direct the spray across the throat so that the spray is deposited on the opposite side (inner) of the feed horn and does not enter the wave guide past the flared throat area.
e. Lighting Systems and Assemblies. External formation lights, wing tip lights, rotating beacons, and anticollision lights are highly susceptible to corrosion. The corrosive attack is usually caused by poor seals which allow moisture intrusion from aircraft wash or from the environment in flight. Interior lights and equipment-mounted bulbs are also susceptible to corrosive attack. In most cases, corrosion will be heaviest at the base of the bulb because of the dissimilar metal contact between the bulb and the bulb socket. Clean and treat as follows:
Par 603 Page 134 WARNING: Ensure that electrical power is disconnected from the light assembly prior to corrosion removal and preservation procedures.
(1) Exterior Mounted Light Assemblies.
(a) Remove the light cover assembly and bulb from the socket in accordance with the OEM’s maintenance instructions.
(b) Remove corrosion using an abrasive nylon mat, conforming to A-A-58054, Type I. Scrub the affected area to loosen corrosion and contaminants.
(c) Clean the affected area with Isopropyl Alcohol, TT-I-735. Use an acid brush with the bristles trimmed back to assist in cleaning the base of the light socket.
(d) After cleaning, re-apply Isopropyl Alcohol, TT-I-735, to the light socket using a squeeze spray bottle to flush out any remaining residue.
(e) Wipe the light socket with a clean cloth or cheesecloth. Allow the area to air dry.
NOTE: The following procedures are applicable only to bulbs that are installed in their sockets with a turning, twisting, or scraping motion (screw base, bayonet base, or fuse-type clip). This scraping metal-to-metal contact is needed to ensure local displacement of the thin, soft film formed by Water-Displacing Corrosion Preventive Compound, MIL-PRF-81309, Type III.
(f) Preserve light assemblies as follows:
1. Apply a thin film of Water-Displacing Corrosion Preventive Compound, MIL-PRF-81309, Type III, to the metal base of the bulb and bulb socket.
2. Wipe to remove excess Corrosion Preventive Compound from the metal base of bulb using a clean cloth or cheesecloth.
3. Install the bulb in the bulb socket.
4. Preserve the outside area of the socket, light assembly, bare metal, and hardware by applying a thin film of Corrosion Preventive Compound, MIL-DTL-85054.
CAUTION: Allow the solvents in the Corrosion Preventive Compound to outgas prior to installing the light lens.
5. Assemble the light assembly. Touch up exterior paint finish as required and in accordance with Chapter 5, subparagraphs 504e and 504f.
(g) On lower fuselage light assemblies, water intrusion and entrapment is a problem during the aircraft wash; clean and preserve after each aircraft wash.
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(2) Interior Lights and Small Equipment Light Assemblies.
(a) Interior lights and small equipment assemblies should be cleaned and preserved in accordance with subparagraphs 603e(1)(a) through 603e(1)(f)3.
(b) Preserve the exterior of the light assembly using Water-Displacing Corrosion Preventive Compound, MIL-PRF-81309, Type II. Assemble the light assembly in accordance with the OEM’s maintenance instructions.
CAUTION: Allow the solvents in the Corrosion Preventive Compound to outgas prior to installing the light assembly.
f. Relay and Circuit Breakers. Remove corrosion and preserve as follows:
NOTE: Corrosion (tarnish) removal is required on most types of contacts.
Tarnish acts as an insulator on contacts. Sliding-type contacts have a self-cleaning action, and tarnish removal is not required if a bright surface area is visible. Relay and circuit breaker contact areas are usually plated with a highly conductive metal. Care should be taken to avoid removing this plating. If the plating is removed during cleaning, replace the relay or circuit breaker.
(1) Heavy corrosion and tarnish may be removed by rubbing with a typewriter eraser.
Medium corrosion and tarnish may be removed by rubbing with a pencil eraser.
(2) Rinse contacts with cotton swabs moistened with Isopropyl Alcohol, TT-I-735.
Clean the remainder of the relay or circuit breaker with an acid brush wet with Isopropyl Alcohol, TT-I-735. Pipe cleaners may be used in hard-to-reach areas to assist in swabbing residue.
(3) Remove Isopropyl Alcohol, TT-I-735, from relays or circuit breakers using a clean cloth or cheesecloth. Allow to air dry.
(4) Preserve relays and circuit breakers as follows:
(a) Apply a thin film of Water-Displacing Corrosion Preventive Compound, MIL-PRF-81309, Type III, to all areas of the relay or circuit breaker, avoiding contact and mating areas.
NOTE: After the application of preservative to relays and circuit breakers, it is necessary to ensure removal of the preservative material from all contact points and mating surfaces. Local air pollution regulations may restrict the use of this solvent. Comply with all local air pollution regulations.
CAUTION: Perform a final wipe of the contacts with Isopropyl Alcohol, TT-I-735, or the contacts will not function electrically.
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(b) Wipe the contact points and mating surfaces with a clean cloth, cotton swabs, or pipe cleaners (as applicable), dampened with an approved solvent or Dry Cleaning Solvent, MIL-PRF-680, Type II, to remove Corrosion Preventive Compounds. Perform a final cleaning wipe using a clean cloth, cotton swabs, or pipe cleaners (as applicable), dampened with Isopropyl Alcohol, TT-I-735.
g. Switches. Switches should include all cam-operated toggle, rotary, interlock, and push-button types. Remove corrosion and treat as follows:
NOTE: Local air pollution regulations may restrict the use of this solvent.
Comply with all local air pollution regulations.
CAUTION: Cleaning compounds and solvents may react with some encapsulants or plastics used to form wire harness tubing, wiring coating, conformal coatings, gaskets, seals, etc. Test on a small area for softening or other adverse reactions prior to general application (see Chapter 4, paragraph 405, and Table 4-3).
(1) Apply an approved solvent or Dry Cleaning Solvent, MIL-PRF-680, with an acid brush to remove contaminants.
(2) Wipe with a clean cloth or cheesecloth to remove excess solvent. Allow the switch to air dry.
(3) Switches should be preserved as follows:
NOTE: After the application of preservative to open switch assemblies, remove from the sliding contacts, cams, and contacts.
(a) Apply a thin film of Water-Displacing Corrosion Preventive Compound, MIL-PRF-81309, Type III, to the switch assembly. The cockpit and control box mounted switches should not be preserved on the exposed actuating arm or toggle. This area should be left clear of preservative so as not to hinder flight crew operation.
NOTE: After application of preservative to switches, it is necessary to ensure removal of the preservative material from the contact points and mating surfaces. Local air pollution regulations may restrict the use of this solvent.
Comply with all local air pollution regulations.
CAUTION: Perform a final wipe of the contacts with Isopropyl Alcohol, TT-I-735, or the contacts will not function electrically.
(b) Wipe sliding contacts, cams, and contact points of open switches with a clean cloth, cotton swabs, or pipe cleaners (as applicable), dampened with an approved solvent or Dry Cleaning Solvent, MIL-PRF-680, Type II, to remove Corrosion Preventive Compounds. Perform a final cleaning wipe with a clean cloth, cotton swabs, or pipe cleaners, as applicable, dampened with Isopropyl Alcohol, TT-I-735.
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h. Edge Connectors and Mating Plugs. Edge connectors on PCBs pose a particular corrosion problem because of the thinly plated surfaces. Most plugs and connectors used in microminiature circuit boards are plated with thin layers of gold. This gold is porous, and moisture will penetrate to the base metal, causing corrosion. In addition, the very function of cleaning may create scratches in the plated surfaces which will accelerate the problem. Remove corrosion and preserve as follows:
(1) Remove corrosion and tarnish by rubbing the affected area with a pencil eraser.
Care should be taken not to remove thinly plated surfaces.
NOTE: Local air pollution regulations may restrict the use of this solvent.
Comply with all local air pollution regulations.
(2) Clean the contact areas with an approved solvent or Dry Cleaning Solvent, MIL-PRF-680, using an acid brush. Rinse the affected area with Isopropyl Alcohol, TT-I-735, and wipe with a clean cloth or cheesecloth. Allow the component to air dry.
(3) Edge connectors should be preserved as follows:
(a) Spray a thin coating of Water-Displacing Corrosion Preventive Compound on both male and female sections of the connector, conforming to MIL-PRF-81309, Type III.
(b) Wipe off excess preservative with a clean cloth or cheesecloth.
i. Wet-Slug Tantalum Capacitors. Wet-slug tantalum capacitors can be internally damaged in service or during repair by the application of a reverse voltage. Such damage will often result in acid leakage which may cause corrosion in areas adjacent to the damaged capacitor. Capacitors having evidence of leakage should be replaced and all adjacent areas cleaned to prevent further corrosion. The following procedures should apply for the inspection of wet-slug tantalum capacitors:
(1) Inspect the seam between the slug and the case of each tantalum capacitor for evidence of small deposits of silver. The color of the silver deposit may be black or gray. When silver deposits are discovered, determine which capacitor is leaking, and then place one drop of the following solution on the suspected capacitor at the seam between the slug and the case and on the silver deposit.
(a) Dissolve 1/4 teaspoon of Thymol Blue Reagent indicator crystals in 3 cups (24 ounces) of deionized or distilled water, conforming to A-A-59282.
NOTE: Verify the color of the Thymol Blue Reagent indicator solution on a piece of white paper prior to use. The color of the solution should be amber or blue. If a reddish-purple color is indicated, the solution is contaminated and should be disposed of properly.
(b) Add 8 drops of ammonium hydroxide, conforming to O-A-451, to the Thymol Blue Reagent indicator and water solution. The ammonium hydroxide will aid in dissolving the Thymol Blue Reagent indicator crystals.