What to do if Yanmar 4BY starter motor brushes are worn out?
If the starter motor brushes are not worn, replace the armature assembly. Otherwise, inspect the brushes and replace them if they show signs of wear.
General| Engine Model | 4BY |
|---|---|
| Engine Type | 4-stroke |
| Number of Cylinders | 4 |
| Fuel System | Direct injection |
| Lubrication System | Forced lubricating system |
| Starting System | Electric starter |
| Cooling System | Water-cooled |
NEVER remove the coolant filler cap if the engine is hot. Steam and hot engine coolant will escape and seriously burn you.
Keep fire extinguishers handy in case of fire. Clearly indicate the location of the fire extinguishers with a safety sign.
Diesel fuel is flammable and explosive under certain conditions.
NEVER check the remaining battery charge by shorting out the terminals. This will result in a spark and may cause an explosion or fire.
When you need to transport an engine for repair, have a helper assist you to attach it to a hoist and load it on a truck.
Keep hands and other body parts away from moving / rotating parts such as the flywheel or PTO shaft.
Avoid skin contact with high pressure diesel fuel spray caused by a fuel system leak such as a broken fuel injection line.
Turn off the battery switch (if equipped) or disconnect the negative battery cable before servicing the electrical system.
Keep your hands and other body parts away from hot engine surfaces such as the muffler, exhaust pipe, turbocharger and engine block during operation and shortly after you shut the engine down.
NEVER operate the engine in an enclosed area such as a garage, tunnel, underground room, manhole or ship’s hold without proper ventilation.
Wear eye protection and rubber gloves when you handle Long Life engine coolant.
ALWAYS wear eye protection when servicing the engine and when using compressed air or high-pressure water.
Use care not to catch finger between belt and pulley while installing belt.
Other engine oils may affect warranty coverage, cause internal engine components to seize and / or shorten engine life.
Other engine coolants may affect warranty coverage, cause an internal buildup of rust and scale and / or shorten engine life.
This may damage the starter motor pinion and / or ring gear.
Water will damage the alternator and result in inadequate charging.
Engine damage will result.
NEVER operate the engine while you are under the influence of alcohol or drugs.
Always read and follow safety related precautions found on containers of hazardous substances like parts cleaners, primers, sealants and sealant removers.
Be sure the boat is in open water away from other boats, docks, and other obstructions before increasing rpm.
Follow the guidelines of the EPA or other governmental agencies for the proper disposal of hazardous materials.
Summarizes maintenance items and intervals for daily, 50, 250, and 500 hours.
Step-by-step procedures for maintenance tasks at different intervals.
Procedures for cylinder head removal, disassembly, and installation.
Procedures for removing, inspecting, assembling, and installing pistons and connecting rods.
Procedures for servicing the camshaft and timing gear train.
Procedure to check and adjust the camshaft timing.
Step-by-step instructions for adjusting camshaft timing.
Procedure for removing the camshafts.
Procedure for installing the camshafts.
Procedures for servicing the cylinder block and crankshaft.
Steps for removing the crankshaft from the engine block.
Steps for installing the crankshaft with bearing shells.
Procedure to replace engine oil and oil filter element.
Steps for removing the turbocharger from the engine.
Diagnostic chart to identify and resolve starter motor problems.
Safety warnings and precautions before servicing electrical system and ECU.
Provides a chart to diagnose problems and their causes/actions.
Troubleshooting steps for engine starting problems.
Troubleshooting guide for different exhaust smoke colors.
Troubleshooting for vibration when the drive is disengaged.
Troubleshooting for vibration when the drive is engaged.
Troubleshooting guide for engine knocking issues.
Troubleshooting guide for low engine power output.
Troubleshooting guide for engine overheating.
Troubleshooting guide for engine running cold.
Troubleshooting guide for coolant loss issues.
Troubleshooting guide for issues with the helm panel display.
Information on diagnostic trouble codes and working procedure.
Lists diagnostic trouble codes, their failures, modes, and conditions.
To Next Page
