Lewmar bow thruster brush wear is a common maintenance issue for boat owners relying on precise docking and maneuvering. If left unchecked, worn brushes can lead to thruster failure, poor performance, or even costly repairs. In this guide, we’ll walk you through how to recognize the signs, inspect your unit, and replace the brushes properly.
⚠️ Signs of Bow Thruster Brush Wear
- Loss of thrust power during operation
- Intermittent performance or slow response
- Visible sparks or electrical noise
- Unusual smells from the thruster compartment
- Motor fails to engage or cuts out unexpectedly
🧰 Tools You’ll Need
- Screwdrivers (Phillips and flat-head)
- Multimeter (to check continuity)
- Replacement brushes (OEM recommended)
- Cleaning brush and vacuum
- Protective gloves and safety glasses
🔧 Step-by-Step Guide to Inspect and Replace Brushes
- Disconnect the battery: Safety first. Make sure the thruster is fully powered off.
- Access the thruster motor: Remove the inspection hatch or motor cover.
- Locate the brushes: Usually found on either side of the armature within the motor housing.
- Check for wear: Brushes should be at least 1/4” (6mm) long. If shorter, replace immediately.
- Remove and clean: Carefully detach the brushes and clean the brush holders and commutator.
- Install new brushes: Use OEM Lewmar parts for best compatibility and performance.
- Test the motor: Reconnect power and verify proper function before sealing everything back up.
💡 Maintenance Tips
- Check the brushes every 100–150 operating hours
- Keep the thruster compartment dry and well-ventilated
- Use dielectric grease on terminals to reduce corrosion
- Consider annual inspections as part of your regular boat maintenance
📦 Shop Lewmar Replacement Brushes
Need new parts? Browse our collection of Lewmar bow thruster brushes and maintenance kits to keep your system running smoothly.