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What Happens During a Mercury Winter Service?

Published October 30, 2026

Wondering what happens when you book a winter service? It is more than a quick check: it is a chance to give your Mercury outboard expert attention while your boat is out of use.

Your authorised Mercury Marine dealer will tailor the work to your engine, its service history and how you use your boat. Here are some of the checks and maintenance that may be included.

Under the Cowl: What Gets Checked?

Every engine is different, and the work required will depend on your model, service history and how you've used your boat. However, a typical winterisation service may include:

Fresh oil, ready for storage

For applicable four-stroke engines, the technician will check the service schedule and change the engine oil and filter where required. Fresh oil helps protect internal components during the months ahead.

Fuel system protection

Fuel can deteriorate during long periods of inactivity. Your dealer can prepare the fuel system for storage, using the appropriate fuel care products and procedures for your engine.

Gearcase checks

The gear lubricant is inspected and changed where required. Signs of water contamination can flag a potential problem that needs attention before freezing temperatures arrive.

Cooling system care

Your engine's cooling system is checked and flushed in accordance with the manufacturer's guidance. This helps remove salt and other deposits, while the correct storage procedure helps protect against potential freeze damage.

Propeller, anodes and corrosion checks

The technician can inspect the propeller and propeller shaft, check sacrificial anodes for wear, lubricate specified points and apply suitable corrosion protection where recommended.

A closer look at the details

A professional service can also identify issues you might not spot yourself, from loose connections and worn components to adjustments that could affect engine performance.

Why Service It Before Spring?

It's tempting to put maintenance off until you're ready to get back on the water. But dealing with potential issues during the quieter winter months gives you time to arrange any necessary repairs before the new season begins.

You'll also have the reassurance that your engine has received attention from a trained technician using the appropriate parts, lubricants and service procedures.

Give Your Mercury the Care It Deserves

Winterisation requirements vary between engines, so your dealer will follow the relevant maintenance schedule and storage guidance for your particular model. Additional servicing or repairs may be recommended depending on the engine's condition.

Ready to give your outboard some attention before winter sets in?

Give your Mercury expert care for less. Contact your local authorised Mercury Marine dealer to book your service and claim your 10% off.

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