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General safety advice, including fire prevention and handling of moving parts.
Precautions for handling batteries, including avoiding smoking and proper connection.
Safety measures for fuel handling, storage, and system integrity.
Hazards associated with exhaust gases, including carbon monoxide poisoning.
Caution regarding hot coolant and opening pressurized systems.
Importance of keeping the unit and surrounding area clean to prevent fire hazards.
Detailed specifications for engine dimensions, clearances, and tolerances.
Recommended torques for assembly and list of specialized tools for service.
A guide to diagnose and resolve common engine problems.
Recommended intervals for engine service and maintenance tasks.
Specifications related to the engine's exhaust system performance.
Technical data for the engine's cooling system components and operation.
Specifications related to the engine's fuel system and components.
Specifications for the engine's lubrication system and oil requirements.
Specifications for the engine's governor system and its function.
Specifications related to the engine's starting system components.
General outline for the process of engine disassembly.
Overview of the engine's control system and its components.
Explains the manual's purpose and how to use its sections for engine servicing.
Guide on how to identify engine models and interpret specification numbers.
Key performance metrics including bore, stroke, displacement, and compression ratio.
Details on crankshaft rotation, governor type, and valve clearances.
Information on the oil filter type and crankcase oil capacity.
Specifications for battery group size and performance at various temperatures.
Detailed measurements for camshaft journals, tappet diameters, and end play.
Specifications for connecting rod bore diameters and end play.
Dimensions for cylinder bore and crankshaft journal clearances.
Specifications for piston ring groove width, ring gap, and piston pin clearance.
Details for starting motor rotation, pinion clearance, and armature end play.
Specifications for intake valve stem diameter, face, and guide clearance.
Specifications for exhaust valve stem diameter, guide clearance, and face angle.
Dimensions for valve guides and valve seats, including angles and oversizes.
Load requirements for valve springs at closed and open positions.
Recommended torque values for various engine assembly fasteners.
A list of specialized tools available from Onan for engine repair.
Common issues and causes related to the engine's starting system.
Troubleshooting steps for fuel system problems like misfires and poor fuel flow.
Diagnosing issues related to oil pressure, consumption, and leaks.
Identifying and resolving problems with the engine governor's performance.
Addressing issues like overheating, coolant loss, and thermostat faults.
Diagnosing problems related to internal engine components like pistons and bearings.
Essential checks and preparations before starting the engine.
Guidance on selecting the correct SAE viscosity grade and API classification for engine oil.
Details on the recommended diesel fuel grade, cetane number, and handling.
Step-by-step instructions for removing air from the fuel system.
Procedures for pre-heating and starting the engine, especially in cold weather.
Instructions on how to properly shut down the engine.
A comprehensive guide for starting industrial diesel engines.
Emphasizes the critical need for fuel system cleanliness to prevent pump failure.
Interpreting exhaust smoke to diagnose fuel delivery issues.
Procedures for inspecting the preheat system and fuel supply for starting problems.
Guidelines for automatic starting controls and applying load to the engine.
Recommended steps for breaking in a new or overhauled engine.
Importance of inspecting the entire engine installation for alignment and safety.
Ensuring adequate airflow for cooling and combustion.
Recommendations for operating the engine in cold temperatures.
Key considerations for proper installation of exhaust systems.
Regular checks for battery condition, connections, and electrolyte levels.
Procedures for keeping the engine clean from dust and dirt.
Understanding power reduction and adjustments for high altitude operation.
Step-by-step guide for changing the engine's oil filter.
Instructions for installing an oil drain extension for easier servicing.
Cleaning and maintaining the crankcase breather system.
Information on the fuel transfer pump and the dual fuel filter system.
Steps to protect the engine when it is out of service for extended periods.
Procedures for preparing a stored engine for operation.
Warning about battery gases and the risk of explosion during servicing.
Warning about the risk of severe injury or death from accidental engine starting.
Essential requirements for the exhaust system, including back pressure limits.
Understanding different exhaust smoke colors and their causes.
Key considerations for proper installation of exhaust systems.
Methods to reduce exhaust noise levels.
Specific guidelines for installing exhaust systems in indoor environments.
Charts showing maximum pipe lengths for different systems with muffler.
Data on the equivalent length added by various pipe fittings.
Critical warning about the deadly nature of exhaust gases and symptoms of poisoning.
Explains the role of the cooling system in engine operation and preventing damage.
Importance of anti-freeze for preventing corrosion and freeze-up.
Function of the switch that shuts down the engine due to high temperatures.
Recommended tasks for maintaining the cooling system's efficiency.
Procedures for cleaning and flushing the cooling system to remove deposits.
Warnings regarding contact with hot coolant and cleaning solutions.
Identifying internal and external coolant leaks and their causes.
Procedures for testing thermostat operation and replacing it when faulty.
Proper methods for draining the cooling system to prevent trapped water.
Explanation of the pressure cap's role in raising boiling point and its maintenance.
How the radiator cooled system circulates coolant through the engine.
Details on the centrifugal water pump and its maintenance requirements.
Step-by-step instructions for removing and installing the water pump.
How the city water cooled system manages coolant flow and temperature.
Description of the optional heat exchanger system with two water circuits.
Maintenance for the closed water portion of the heat exchanger system.
Periodic checks for air leaks, wear, and restrictions in the open water system.
Steps for disassembling the water pump for inspection and repair.
Instructions for assembling the water pump and setting critical clearances.
Properties of diesel fuel including its composition and heat content.
Importance of pour point for cold weather fuel selection.
Essential procedures for maintaining fuel cleanliness and preventing water contamination.
Description of the fuel system parts and how fuel is delivered to injectors.
Information on the sediment bowl, primary, and secondary fuel filters.
Guidelines for installing fuel tanks and lines, including siphon breaks.
How the fuel transfer pump operates to deliver fuel.
Steps for removing and disassembling the fuel transfer pump.
How diesel injectors work and how to install them correctly.
Detailed explanation of how the fuel injector operates.
Methods for checking the spray pattern to diagnose nozzle defects.
Procedures for adjusting nozzle pressure and disassembling nozzles.
Detailed steps for cleaning injection nozzles and their components.
How to use a nozzle tester for checking and adjusting nozzle pressure.
Proper procedures for installing injection nozzles into the cylinder head.
Explanation of the fuel shutoff solenoid's role in engine operation.
Instructions for repairing and assembling injection nozzles.
Description of the 12-volt circuit for manifold heaters and glow plugs.
Emphasizes professional repair for injection pumps and cautions against unauthorized work.
Information on the PSU injection pump used in 4-cylinder engines.
Introduction to the PSU fuel injection pumps used on the diesel engines.
How the PSU pump is driven by the camshaft and its internal rotation.
Detailed explanation of the pump's internal components and operation.
How the metering sleeve controls fuel delivery based on the governor lever.
Information on timing button codes, sizes, and their importance for pump timing.
Procedure for calculating the correct timing button thickness based on old pump dimensions.
Formula used to determine the correct timing button for new or replacement pumps.
Procedure for timing the pump using fuel flow when dimensions are unavailable.
Instructions for assembling the delivery valve in late and early model pumps.
How to connect fuel lines from the pump to the injectors.
Method for checking the port closing position relative to flywheel marks.
Steps for manually operating the fuel transfer pump to check fuel flow.
How to verify timing correctness and adjust the timing button if needed.
Procedures for mounting the pump and ensuring proper gear meshing.
How to lock the drive gear to facilitate injection pump installation.
How the delivery valve maintains line pressure in the injector lines.
Steps for bleeding air from the fuel system after filter changes or maintenance.
Description of the engine's oil system, including components and lubrication path.
Procedures for removing, repairing, and installing the oil pump.
How the bypass valve controls oil pressure and how to inspect it.
Instructions for cleaning oil lines and restriction orifices in the rocker box.
Information on oil line placement and the function of restriction orifices.
Steps for replacing the full-flow oil filter and associated warnings.
Procedures for cleaning and maintaining the crankcase breather system.
Explains the governor's role in maintaining constant engine speed.
How to maintain the governor linkage for proper movement and lubrication.
Procedures for testing spring rates and inspecting governor parts.
How to adjust engine speed by changing governor spring tension.
How to adjust governor sensitivity to control engine response to load changes.
Warning about potential injury from contact with rotating machinery.
Description of the starter motor, solenoid, and their engagement with the flywheel.
Routine checks for wiring, commutator, and brushes in the starting circuit.
Methods for diagnosing poor cranking performance related to battery or circuit resistance.
How to check battery charge condition using a hydrometer.
Inspecting and adjusting the battery charging system for proper battery maintenance.
Detailed instructions for repairing starter motor components like armature, fields, and bearings.
When and how to replace starter motor brushes for optimal performance.
Inspecting the over-running clutch and shifting solenoid for proper function.
Step-by-step instructions for removing and disassembling the Prestolite starter motor.
Guidelines for assembling the Prestolite starter, including bearing preparation and end play.
Instructions for removing and installing the Mitsubishi starter motor.
Detailed steps for disassembling the Mitsubishi starter motor.
General instructions for reassembling the Mitsubishi starter motor.
How to adjust the end play of the pinion shaft for proper starter engagement.
Steps for installing the pinion gear onto the pinion shaft.
Correct procedure for installing the starter lever assembly, spring, and packing.
How to adjust the pinion gap for correct starter engagement.
Steps for removing the brush assembly from the alternator.
Tests to check the continuity and shorts of the alternator brush assembly.
General steps and considerations for engine disassembly.
Procedures for reassembling engine components, emphasizing cleanliness and proper fit.
Tips and special tools recommended for successful engine assembly.
Interval checks for valve clearances and combustion chamber cleaning.
Step-by-step guide for adjusting valve clearances on cold engines.
Procedures for adjusting valve clearances on remaining engine cylinders.
How to perform a compression test to assess engine internal condition.
Steps for removing cylinder heads and their components.
Procedures for cleaning the valve seat counterbore and installing new seats.
Installing valve springs, retainers, and stem seals.
Sequence and torque specifications for installing cylinder heads.
How to remove and install the flywheel, including timing mark location.
Steps for removing the gear cover and servicing the governor shaft.
Instructions for replacing the oil seal in the gear cover.
Assembling the gear cover and ensuring proper governor cup fit.
Checking governor cup and flyballs for wear and proper seating.
Introduction to piston, ring, and connecting rod components.
Steps for removing pistons and inspecting cylinder walls for wear.
How to clean and inspect pistons, rings, and check ring gap.
Inspecting piston pins for fit and connecting rod bushings for clearance.
Checking connecting rod bearings for wear and measuring clearance.
Procedures for assembling connecting rods to pistons and crankshaft.
Steps for removing the camshaft from the engine.
How to remove the camshaft gear and service camshaft bearings.
Pressing in new camshaft bearings and installing expansion plugs.
Installing the camshaft gear, governor components, and timing the camshaft.
Overview of the crankshaft's construction and features.
Steps for removing the crankshaft gear using specialized tools.
How to inspect crankshaft journals and procedures for grinding.
Steps for shot-peening crankpin fillets for increased durability.
Procedures for replacing main bearings and installing the crankshaft.
Installing main bearings, thrust washers, and torquing bearing caps.
Adjusting crankshaft end play using shims and gaskets.
What to do if the crankcase needs replacement, including shims and timing.
Recommended procedure for running in the engine after major repairs.
Explains that controls are usually supplied by the equipment manufacturer.
Importance of checking all control system connections for tightness and cleanliness.
Schematic showing the wiring for a typical standard engine control system.
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