Before you start
Gather the appropriate supplies and review the specific equipment manual.
- Engine cooling-system diagram
- Flashlight
- Service record
Step-by-step instructions
Wait for a fully cool engine
Shut down and allow the cooling system to cool according to its manual before inspecting accessible hoses. Hot coolant and pressure can cause serious burns.
Locate the main hose runs
Identify expansion tank, heat exchanger and engine-to-pump hoses. Different models use different hose routing and fittings.
Look for external wear
Check accessible areas for cracking, swelling, soft spots, salt or coolant staining, chafe near metal edges and unsupported bends.
Review the clamps
Watch for corrosion, unusual clamp placement or evidence of weeping without loosening a clamp on a filled, pressurized system.
Document and replace correctly
Record uncertain hose sections and have them changed using coolant-compatible marine hose, correct dimensions and manufacturer-approved clamps.
Safety note
Never remove a radiator or expansion cap from a hot pressurized cooling system. A cooling hose failure can destroy the engine.
Key takeaway
A quick visual hose inspection can catch a major future failure.
Keep this job on your maintenance schedule
Save the topic as a maintenance task, choose a due date or engine-hour target, and record future service. Free and stored on your device.
Add to my maintenance plannerThis guide is for general education. Follow your equipment manufacturer’s instructions, current navigation guidance and applicable marine safety standards. When uncertain, use a qualified marine professional.