MicroLite 4000 Series

1 Printed 97 MicroLite 4000 SeriesKYTable of ContentsiSECTIONTITLEPAGESAFETY PRECAUTIONSiii.. 1 INTRODUCTION1-1.. 2 SPECIFICATIONS2-1.. 3 dimensions AND CLEARANCES3-1.. 4 TORQUE SPECIFICATIONS4-1.. 5 PREPARING FOR SERVICE5-1.. Troubleshooting5-1.. Special Tools5-1.. Safety Considerations5-1.. Set Removal Guidelines5-2.. 6 TROUBLESHOOTING6-1.. Introduction6-1.. Generator Troubleshooting6-28.. Engine Primary Systems Troubleshooting6-32.. 7 CONTROL7-1.. Introduction7-1.. Control Description7-1.. Control Operation7-3.. Control Component Tests7-5.. 8 PRIMARY ENGINE SYSTEMS8-1.. Introduction8-1.. Cooling System8-1.. Exhaust System8-2.

2 Ignition System8-6.. Crankcase Ventilation System8-8.. Governor8-9.. Gasoline Fuel System8-11.. LPG Fuel System8-21.. Electric Starter8-25.. The engine exhaust from this productcontains chemicals known to the Stateof California to cause cancer, birth defects or other reproductive harm.!!ii9 GENERATOR9-1.. Generator Description9-1.. Generator Operation9-2.. Generator Service9-2.. Generator Testing9-8.. Voltage Regulator (VR1) Test9-12.. Brushes and Slip Rings9-12.. Rotor Bearing Replacement9-13.. 10 ENGINE BLOCK ASSEMBLY10-1.. Introduction10-1.. Leak Down Test10-1.. Oil Pan and Oil Level Switch10-2.. Head Cover10-2.. Rocker Arms, Push Rods and Cylinder Head10-3.

3 Valve System10-4.. Crankcase Cover10-8.. Governor10-8.. Camshaft, Tappet and Balancer Removal10-9.. Piston and Crankshaft10-9.. Inspection of Engine Parts10-10.. Piston and Crankshaft Installation10-17.. Bearings10-19.. Oil Seal10-19.. Compression Release System10-20.. 11 SERVICE CHECKLIST11-1.. General11-1.. Mounting11-1.. Lubrication11-1.. Wiring11-1.. Initial Start Adjustments11-1.. Exhaust System11-2.. Fuel System11-2.. Output Check11-2.. Control11-2.. Mechanical11-2.. 12 WIRING SCHEMATIC/DIAGRAM12-1.. Safety PrecautionsiiiThoroughly read the SERVICE MANUAL before servic-ing the genset. Reliable service can be obtained onlywith close adherance to the procedures in this following symbols in this Manual alert you to potentialhazards to the operator, service person and equipment.

4 Alerts you to an immediate hazard whichwill result in severe personal injury or Alerts you to a hazard or unsafe practicewhich can result in severe personal injury or Alerts you to a hazard or unsafe practicewhich can result in personal injury or equipment , fuel, exhaust, moving parts and batteries pres-ent hazards which can result in severe personal injury PRECAUTIONS Keep ABC fire extinguishers handy. Make sure all fasteners are secure and torqued prop-erly. Keep the genset and its compartment clean. Excessoil and oily rags can catch fire. Dirt and gear stowed inthe compartment can restrict cooling air. Before working on the genset, disconnect the nega-tive ( ) battery cable at the battery to prevent starting.

5 Use caution when making adjustments while the gen-set is running hot, moving or electrically live partscan cause severe personal injury or death. Used engine oil has been identified by some state andfederal agencies as causing cancer or reproductivetoxicity. Do not ingest, inhale, or contact used oil or itsvapors. Benzene and lead in some gasolines have been iden-tified by some state and federal agencies as causingcancer or reproductive toxicity. Do not ingest, inhaleor contact gasoline or its vapors. Do not work on the genset when mentally or physical-ly fatigued or after consuming alcohol or drugs. Carefully follow all applicable local, state and VOLTAGE IS DEADLY!

6 Generator output connections must be made by aqualified electrician in accordance with applicablecodes. The genset must not be connected to the public utilityor any other source of electrical power. Connectioncould lead to electrocution of utility workers, damageto equipment and fire. An approved switching devicemust be used to prevent interconnections. Use caution when working on live electrical equip-ment. Remove jewelry, make sure clothing and shoesare dry and stand on a dry wooden platform on theground or IS FLAMMABLE AND EXPLOSIVE Keep flames, cigarettes, sparks, pilot lights, electricalarc-producing equipment and switches and all othersources of ignition well away from areas where fuelfumes are present and areas sharing ventilation.

7 Fuel lines must be secured, free of leaks and sepa-rated or shielded from electrical wiring. Use approved non-conductive flexible fuel hose forfuel connections at the EXHAUST IS DEADLY! Learn the symptoms of carbon monoxide poisoning inthis Manual. Never sleep in the vehicle while the genset is runningunless the vehicle has a working carbon monoxidedetector. The exhaust system must be installed in accordancewith the genset Installation Manual. Do not use engine cooling air to heat the vehicle interi-or. Make sure there is ample fresh air when operating thegenset in a confined PARTS CAN CAUSE SEVERE PERSONALINJURY OR DEATH Do not wear loose clothing or jewelry near movingparts such as PTO shafts, fans, belts and pulleys.

8 Keep hands away from moving parts. Keep guards in place over fans, belts, pulleys, GAS IS EXPLOSIVE Wear safety glasses and do not smoke while servic-ing batteries. When disconnecting or reconnecting battery cables,always disconnect the negative ( ) battery cable firstand reconnect it last to reduce Introduction1-1 This is the service manual for the KY 4000 SeriesMicroLite generator sets ( gensets ). Read andcarefully observe all of the instructions and precau-tions in this Improper service or parts replace-ment can lead to severe personal injury or deathand to damage to equipment and property. Ser-vice personnel must be qualified to performelectrical and mechanical Unauthorized modifications or re-placement of fuel, exhaust, air intake or speedcontrol system components that affect engineemissions are prohibited by law in the State LPG (liquified petroleum gas) isflammable and explosive and can cause as-phyxiation.

9 NFPA 58, Section requires allpersons handling LPG to be trained in properhandling and operating the Operator s Manual for instructions con-cerning operation, maintenance and storage andfor recommendations concerning engine lubricat-ing oil and the Installation Manual for important recom-mendations concerning the installation and for a listof the installation codes and standards for safetywhich may be the Parts Manual for parts identification num-bers and required quantities and for exploded viewsof the genset subassemblies. Genuine Onan re-placement parts are recommended for best contacting Onan for parts, service or productinformation, be ready to provide the model numberand the serial number, both of which appear on thegenset nameplate (Figure 1-1).

10 Each character ofthese numbers is significant (Figures 1-2 and 1-3 onPage 1-2).SN5304U1G2RA304 ccA953123456 NAMEPLATE WITH TYPICAL MODEL ANDSERIAL NUMBER DATA4 KYFA26100 EFIGURE 1-1. TYPICAL NAMEPLATEM icroLite is a trademark of the Onan Number IdentificationFigure 1-2 shows a breakdown of the model num-ber for a typical KY FA 26100 E 1 2 3 4 5 61. Power capacity in kilowatts - (4000 watts)2. Product family Starting method - (Remote startable)4. Voltage and frequency code - (120 volt,60-Hz )5. Specification number - (Code for options andspecial features)6. Specification letter - (Used to identify majordesign or manufacturing changes)FIGURE 1-2.