CHAPTER 2 GENERAL MAINTENANCE INSTRUCTIONS

CHAPTER 2 GENERAL MAINTENANCE INSTRUCTIONS Section I. REPAIR PARTS, SPECIAL TOOLS AND EQUIPMENT 2-1. Tools and Repair Parts, Equipment There are no special tools or equipment required to perform intermediate (field) (direct and general support) and depo t maintenance on generator sets Models MEP006A, MEP105A and MEP115A. A listing of recommended tools and support equipment required to perform the maintenance operations described in this manual are contained in Table 2-1. 2-2. Direct Support General Support and Depot Maintenance Repair Parts. Direct and general support and depot maintenance repair parts are contained in the technical manual listed in Appendix A of this manual. 2-4. General. 2-3. Specially Designed (Fabricated) Tools and Equipment. A breakout cable is required to trouble- shoot the electric governor system of MEP - 114A. The breakout cable is used to gain access to the governor Control Unit’s MS3106R20-29 connector. Figure 2-0 g i v e s f a b r i c a t i o n i n s t r u c t i o n s f o r t he breakout cable. Section II. TROUBLESHOOTING This section provides information useful in diagnosing and correcting unsatisfactory opera- tion or failure of the engine generator set and its components. Malfunctions which may occur are listed in table 2-2. Each malfunction stated is followed by a list of probable causes of the trouble. The corrective action is described oppo- site the probable cause. 2-5. Troubleshooting Chart. Table 2-2 lists generator set troubleshooting mal- functions, probable causes and corrective action. 2-6. Diagrams. Wiring, schematic and trouble shooting diagrams for the generator set are listed in the List of Illustrations in the Table of Contents. Refer to the Operator and Organizational Maintenance Manual for diagrams not located in this manual. Section III. RADIO INTERFERENCE SUPPRESSION 2-7. General Methods Used to Attain Proper Suppression. Essentially, suppression is attained by providing a low resistance path to ground for the stray currents. The methods used include grounding the frame with bonding straps, grounding the engine-generator set, and the use of capacitors. 2-8. Testing of Radio Interference Suppression Components. Test the capacitors for leaks and shorts on a capacitor tester: replace defective capacitors. If test equipment is not available and interference is indicated, isolate the cause of interference by the trial and error method of replacing each capacitor in turn until the cause of interference is located and eliminated. 2-9. Interference Suppression Components. a. Primary Suppression Components. components, RFI capacitors, whose primary pur- pose is interference suppression are the three capacitors found on the generator side of CB2, main line contarctor and the three on the input leads to the engine-generator sets load bank. Their description, location and removal are covered in the Operator and Organizational Maintenance Manual. Three suggested methods of grounding the engine- generator set, instrumental in passing RFI induced currents to ground are illustrated in the Operator and Organizational Maintenance Manual. b. Secondary Suppression Components. The components, RFI capacitors whose secondary pur - pose is interference suppression are the components contained within the excitation system assembly. Testing of the RFI filter A201 is described in para- graph 8-12 b (3), utilizing figure 1-8 schematic dia- gram, excitation system assembly. Refer to figure 8-1 for disassembly of the relay table which includes the excitation system assembly, and figure 8-15 for the excitation system assembly. Change 9 2-1