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Table of Contents
- 1 Table of Contents
- 2 General Information
- 3 Specifications
- 4 Dimensions and Clearances
- 5 Assembly Torques and Special Tools
- 6 Engine Troubleshooting
- 7 Service and Maintenance
- 8 Exhaust System
- 9 Cooling System
- 10 Fuel System
- 11 Governor System
- 12 Oilsystem
- 13 Starting System
- 14 Engine Disassembly
- Download this manual
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Table of Contents
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Summarization of Contents
Safety Precautions
General Safety Guidelines
Covers safety codes, moving parts, batteries, fuel, exhaust, cooling, and cleanliness.
General Information
Introduction and Model Reference
Explains manual scope, parts, troubleshooting, and engine model identification.
Dimensions and Clearances
Component Specifications
Details for camshaft, rods, cylinder, crankshaft, pistons, pins, starter, and valves.
Assembly Torques and Special Tools
Special Tools and Torque Values
Lists specialized tools and recommended torque specifications for assembly.
Engine Troubleshooting
Troubleshooting Common Issues
Identifies causes and solutions for problems in starting, fuel, lubrication, governor, cooling, and internal systems.
Service and Maintenance
Pre-Operation Checks and Recommendations
Covers pre-starting checks, oil, and fuel recommendations.
Pre-heating and Starting Procedures
Starting Guide and Stopping
Steps for priming, starting, and stopping the engine.
If Engine Fails to Start
Troubleshooting and Break-In
Steps for diagnosing start failures, applying load, break-in, and inspection.
Exhaust System
General Exhaust Requirements
Function, back pressure limits, and testing of exhaust systems.
Water Cooled Exhaust Systems
Design principles for marine exhaust systems using water cooling.
Exhaust Smoke Interpretation
Identifying engine conditions based on exhaust smoke color.
Typical Exhaust Installations
Above Water Line Installation
Design considerations for exhaust systems above the load water line.
Below Water Line Installation
Design considerations for exhaust systems below the load water line.
Cooling System
Inspection and Maintenance
Checking the cooling system for leaks, wear, and performance.
Draining the Cooling System
Step-by-step instructions for draining coolant from various components.
Filling the Cooling System
Coolant Mixture and Capacities
Recommended antifreeze mixture and system capacities.
Heat Exchanger Filling Procedure
Steps for correctly filling the heat exchanger with coolant.
Marine Cooling Systems
Direct Cooling System
How direct sea water cooling operates, including components.
Water Flow Management
Sea Water System Requirements
Need for continuous sea water flow and filter maintenance.
Water Pump Priming and Flow Check
Procedures for priming the sea water pump and verifying delivery.
Heat Exchangers
Front Mount Heat Exchanger
Description and maintenance of front mount heat exchangers.
Side Mount Heat Exchanger
Description and maintenance of side mount heat exchangers.
Keel Coolers
Keel Cooler System Operation
How keel coolers function and required components.
Captive Water Side Protection
Protecting the captive water side from corrosion and scale.
Marine Water Pumps
Pump Types and Applications
Metal vs. neoprene impeller pumps and their uses.
Water Pump Maintenance
Checking captive and sea water pumps for wear and leaks.
Water Pump Repair Overview
Information on repair kits and pump types.
Water Pumps #132-0110 and #132-0074
Disassembly and Assembly
Steps for disassembling and reassembling metal impeller water pumps.
Water Pump #131-0152
Disassembly and Assembly
Steps for disassembling and reassembling neoprene impeller water pump.
Water Pump #131-0257
Disassembly and Assembly
Steps for disassembling and reassembling neoprene impeller water pump.
Water Pumps #132-0146 and #132-0147
Disassembly and Assembly
Steps for disassembling and reassembling neoprene impeller water pumps.
Water Pump #132-0059
Disassembly and Assembly
Steps for disassembling and reassembling neoprene impeller water pump.
Thermostat
Testing Thermostat Operation
Procedure for testing thermostat opening and closing.
Thermostat Specifications
Specifications for thermostat temperatures and clearances.
Fuel System
Fuel Recommendations
Guidance on selecting quality fuel and handling precautions.
Fuel System Components and Operation
Overview of fuel system, pump, filters, and injectors.
Fuel Transfer Pump
Pump Operation and Repair
How the pump operates, pressure specs, and repair options.
Fuel Pump Removal and Disassembly
Step-by-step instructions for removing and disassembling the pump.
Injection Nozzles
Nozzle Operating Principle and Installation
How nozzles function and procedures for installation.
Nozzle Spray Pattern and Testing
Spray Pattern and Cleaning
Checking spray patterns, nozzle cleaning, and maintenance.
Nozzle Adjustment and Tester Use
Adjusting nozzle pressure and using the injection nozzle tester.
Nozzle Repair and Installation
Nozzle Repair and Installation Procedures
When to repair or replace nozzles and how to install them.
Fuel Injection Pumps
Pump Types and Operation
Overview of American Bosch PLB and PSU pumps and their function.
MDJA Injection Pump
Pump Repair and Removal
Recommendations for injection pump repair and steps for removal.
Injection Pump Timing
How to time the MDJA injection pump using flywheel marks.
Timing PSU or Model 50 Injection Pumps
Method 1: Timing by Calculation
Calculating timing button thickness based on measurements.
Method 2: Flow Timing Injection Pump
Timing the pump by observing fuel flow.
PSU or Model 50 Injection Pump Service
Pump Repair and Removal
Internal repair guidelines and steps for pump removal.
Flow Timing Procedure
Procedure Steps and Diagrams
Detailed steps for performing flow timing and related diagrams.
Engine Performance Impact of Timing
How timing affects engine performance, smoke, and fuel consumption.
Torque Instructions
Bryce/Kiki Pump Torque Specifications
Torque values for Bryce and Kiki pump components.
Bryce/Kiki Fuel Injection Pumps
Pump Identification and Repair
Differences between Bryce and Kiki pumps and general repair.
Injection Pump Adapter
Adapter Function and Maintenance
Role of the adapter and warnings about adjustments.
Bearing and Seal Replacement Procedure
Removal and Caution
Instructions for removing bearings/seals and a caution on dirt.
Camshaft Assembly Installation
Pump and Solenoid Diagrams
Diagrams related to pump mounting and solenoid adjustment.
Flow Timing Procedure
Procedure Steps and Diagrams
Detailed steps for performing flow timing and related diagrams.
Torque Instructions for Bryce/Kiki Pumps
Component Torque Specifications
Torque values for Bryce and Kiki pump components.
Troubleshooting Injection Pump Problems
Visual Checks and Slide Test
Inspecting nozzles for damage and testing valve seating.
Nozzle Testing with Hand Operated Tester
Test Procedures and Kiki Adjustment
Testing nozzles and adjusting Kiki nozzle pressure.
Yanmar-American Bosch Nozzle Adjustment
Adjusting Yanmar/Bosch nozzle opening pressure.
Nozzle Performance Tests
Opening Pressure, Leakage, and Chatter
Tests for nozzle opening pressure, leakage, and chatter.
Spray Pattern and Bleeding Procedures
Correct spray patterns and bleeding the fuel system.
Governor System
Governor Operation and Maintenance
How governors maintain speed and linkage maintenance.
Speed and Sensitivity Adjustments
Adjusting governed speed and sensitivity on various models.
MDJA Governor System Adjustments
Speed and Sensitivity Adjustment
Adjusting speed and sensitivity on MDJA models.
Governor Diagrams
Diagrams of MDJA governor assemblies and adjustments.
Oil System
Oil Pressure System Overview
Components and function of the engine's lubrication system.
Oil Pump Service
Oil pump operation, removal, and repair.
Crankcase Breather Systems
MDJA/MDJB/MDJE Breather
Crankcase breather system for specific MDJA, MDJB, MDJE models.
MDJC/MDJF Breather Pipe
Crankcase breather pipe system for MDJC, MDJF models.
Centrifugal Switch Service
Repair and Assembly
Repairing and assembling the centrifugal switch.
Starting System
System Overview and Maintenance
Description of the starting motor, solenoid, clutch, and basic maintenance.
Starting System Testing
Troubleshooting poor cranking performance related to motor, battery, or resistance.
Starter Motor Testing
Stall Torque and Field Coil Tests
Procedures for testing starter motor stall torque and field coils.
Prestolite Starter Service
Removal and Disassembly
Steps for removing and disassembling the Prestolite starter.
Assembly and End Play Adjustment
Assembling the Prestolite starter and adjusting pinion shaft end play.
Mitsubishi Starter Service
Removal and Installation
Procedures for removing and installing the Mitsubishi starter.
Disassembly Procedure
Steps for disassembling the Mitsubishi starter.
Mitsubishi Starter Assembly
Assembly Procedure and Lubrication
Steps for assembling the Mitsubishi starter, including greasing points.
Pinion Shaft End Play Adjustment
Adjusting end play using washers.
Belt Driven Alternator Service
Brush Assembly Maintenance
Removing and testing alternator brushes.
Engine Disassembly and Rebuilding
Disassembly Procedure
Suggested order of disassembly for engine components.
Engine Assembly Guidelines
General guidelines for engine assembly using genuine parts and suggestions.
Engine Assembly and Maintenance
Continued Disassembly and Maintenance
Further disassembly steps and regular maintenance tasks.
Valve Clearance Adjustments
Procedures for adjusting valve clearance on two and four-cylinder engines.
Valve Clearance Adjustments
Adjustment Procedures and Diagrams
Detailed steps for adjusting valve clearance and related diagrams.
Cylinder Heads and Valves Disassembly
Component Overview and Disassembly
Description of cylinder head parts and steps for disassembly.
Valve and Seat Repair
Cleaning, refacing, and replacing valves and valve seats.
Valve and Head Assembly
Assembly Procedure and Torque
Steps for assembling valve components and cylinder heads with torque sequence.
MDJA Decompression Release
Mechanism Operation and Adjustment
How the decompression release works and how to adjust it.
Internal Disassembly Procedures
Flywheel and Gear Cover Removal
Procedures for removing the flywheel, ring gear, and gear cover.
Governor Shaft and Oil Seal Service
Removing the governor shaft and replacing the gear cover oil seal.
Governor Cup Service
Cup Removal, Repair, and Installation
Procedures for removing, repairing, and installing the governor cup.
Pistons, Rings, and Connecting Rods
Component Description and Assembly
Details on pistons, rings, pins, and rod bearings, and their assembly.
Piston Assembly Removal and Cylinder Inspection
Piston, Ring, and Pin Removal
Steps for removing pistons, rings, and pins.
Cylinder and Piston Inspection
Checking cylinder walls and pistons for wear.
Ring and Connecting Rod Inspection
Ring and Rod Inspection
Inspecting piston rings, connecting rods, and bearings.
Camshaft Service
Camshaft Removal and Repair
Procedures for removing and repairing the camshaft.
Camshaft Gear Removal
Procedure for removing the camshaft gear.
Camshaft Bearings Service
Bearing Installation and Measurement
Pressing in bearings and measuring end play.
Camshaft Assembly Installation
Timing Gear Alignment and Assembly
Aligning timing marks and installing camshaft assembly.
Main Bearings and Rear Oil Seal
Main Bearing Replacement
Replacing main bearings due to clearance or wear.
Rear Oil Seal Replacement
Procedure for replacing the rear crankshaft oil seal.
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