0331188 JOHNSON O-RING, Cover

Introduction
Do not perform any procedure in this Special Instruction until you read this information and you understand this information.This Special Instruction provides the following information for CG137-08 and CG137-12 Engines:
Required information
Requirements for the electrical system
Grounding practices
Proper welding practices
Service tools
Wiring connections
Initial start-up procedures
Governor adjustment proceduresReference: The following information is required in order to perform the installation and initial start-up:
Complete analysis of the fuel
Data from a complete fuel analysis that is entered into Caterpillar Software, LEKQ6378, "Methane Number Program"
The performance data sheet for this engine located in the Technical Marketing Information (TMI) database
Operation and Maintenance Manual, SEBU8553
Systems Operation/Testing and Adjusting, KENR9788
Troubleshooting, KENR9788
Electrical Schematic, UENR1215
Gas Compression Operator Control Panel Manual, UENR3193Required Information
Ignition Timing
A complete fuel analysis must be conducted prior to putting the engine into service. Obtain a fuel analysis in order to determine the fuel energy content and calculate the methane number. The methane number indicates the ability of the fuel to be ignited. The methane number is determined when you input the data from the fuel analysis into the Methane Number Program, LEKQ6378. Use the methane number and the Engine Performance, "Fuel Usage Guide" in order to determine the ignition timing.Obtain several samples of fuel if the quality is expected to change. If the methane number will vary during engine operation, use the lowest expected value in order to determine ignition timing.Maximum Load
Refer to TMI to determine the engine power level for the altitude, the temperature, and the methane number. Use the information in the Engine Performance, LEBQ6117 to determine the maximum engine load. The desired engine load must not exceed the maximum engine load.Inlet Manifold Pressure at Full Load
Use the inlet manifold pressure to estimate the engines load. The inlet manifold pressure may be used if the engine timing and the exhaust O2 % are set properly. Refer to TMI to determine the inlet manifold pressures for specific settings of timing and emissions. If the engine power is derated, interpolate the desired inlet manifold pressure between the 100 percent and the 75 percent load ratings.Level of Exhaust Emissions
An emissions analyzer is required to set up this engine. The engine performance Data Sheet gives the levels of emissions for engine loads of 50 percent, of 75 percent, and of 100 percent. Set up the engine in accordance with the Data Sheet at the desired full load with the data that was taken at 100 percent load.Note: Use O2 % levels to set up the engine, when possible.Gas Pressure Regulator
The gas pressure regulator requires adjustment when the engine is installed. Use only Caterpillar© approved regulators in order to avoid problems with performance. A balance line for the regulator is required on all gas engines. This line compensates for changes in boost pressure or in air filter restriction.Note: The supply line to the gas pressure regulator must be of adequate diameter to provide constant pressure to the regulator from idle to full load. Do not use supply lines that are smaller than the inlet to the pressure regulator.Requirements for the Electrical System
When you route the wiring, avoid acute bends and sharp edges. To protect the wiring harnesses, route the harnesses through the metal conduit. A liquid tight conduit is recommended. Use proper support and alignment in order to avoid strain on the conduit.The engine control system requires a clean 24 VDC power supply. The maximum allowable AC ripple voltage is 150 mV AC peak-to-peak. For the wiring, the maximum allowable voltage drop is 1 VDC from the power supply to the Electronic Control Module (ECM) or to an actuator. The power supply must be rated at 20 amp of continuous power.Grounding Practices
Proper grounding is necessary for optimum engine performance and reliability. Improper grounding will result in electrical current paths that are uncontrolled and unreliable.Uncontrolled electrical circuit paths can result in damage to main bearings, to crankshaft bearing journal surfaces, and to aluminum components. Uncontrolled electrical circuit paths can also cause electrical activity that may degrade the engine electronics and communications.
For the starting motor, do not attach the battery negative terminal to the cylinder block.
Use an electrical ground strap to connect all metal cases that contain electrical components or electronic components to the cylinder block.
Do not connect the negative terminal from the electrical power supply directly to the cylinder block. Connect the negative terminal from the electrical power supply to the negative terminal "−" on the interface box.
Ground the cylinder block with a ground strap. The strap is furnished by the customer. Connect this ground strap to the ground plane.
Use a separate ground strap to ground the battery negative terminal for the control system to the ground plane or to earth ground.
Rubber couplings may connect the steel piping of the cooling system and the radiator. This action causes the piping and the radiator to be electrically isolated. Ensure that the piping and the radiator are continuously grounded to the cylinder block. Use ground straps that bypass the rubber couplings.
Ensure that all grounds are secure and free of corrosion.Proper Welding Procedures
Proper welding procedures are necessary in order to avoid damage to electronic controls. Perform welding on the engine according to the following procedure.
Set the engine control to the "STOP" mode.
Turn off the fuel supply to the engine.
Disconnect the negative terminal from the power supply.
Disconnect the following electronic components from the wiring harnesses: ECM, throttle actuator, fuel actuator and all sensors.
Protect the wiring harnesses from welding debris and/or from the welding spatter.
Do NOT use electrical components (ECM or sensors) or electronic component grounding points for grounding the welder.
Connect the welders ground cable directly to the engine component that will be welded. Place the clamp as close as possible to the weld. This placement will reduce the possibility of welding current damage to the engine bearings, electrical components, and to other engine components.
Use standard welding procedures to the weld the materials together.Service Tools
The following tools are required in order to perform the electrical installation and the initial start-up.
Personal computer (PC)
Cat © Electronic Technician (ET)
317-7484 Communication Adapter Gp
1U-5470 Engine Pressure Gp or water manometer
1U-5804 Crimp Tool