Winterization & Storage
Professional winterization, storage, and spring commissioning for outboards, inboards, generators, pumps, and transmissions. Protect your investment from freeze damage, corrosion, and fuel degradation during the off-season.
❄️ Winterization Services
Outboard Motor Winterization
Complete protection for 2-stroke and 4-stroke outboards, including EFI and carbureted models.
- Freshwater flush and cooling system drain
- Fuel stabilization and tank top-up
- Cylinder fogging and spark plug preservation
- Engine oil and filter change (4-stroke)
- Lower unit gear oil drain and refill
- Water pump impeller inspection
- Grease pivot points and steering linkage
- Propeller removal, inspection, and anti-corrosion treatment
- Full shrink-wrap or breathable cover option
Inboard & Diesel Winterization
Comprehensive protection for marine diesel and gasoline inboards, including closed and raw-water cooling systems.
- Raw-water system flush and drain
- Closed cooling system drain and refill with antifreeze
- Heat exchanger and oil cooler inspection
- Engine oil and filter change
- Fuel filter replacement and water separator drain
- Fuel tank stabilization and biocide treatment
- Exhaust elbow and riser drain
- Raw-water pump impeller removal and storage
- Battery disconnection and trickle-charger setup
- Intake and exhaust port sealing
Generator Winterization
Protect your auxiliary power source from cold-start damage and fuel system degradation.
- Load bank test before shutdown
- Cooling system drain and antifreeze refill
- Engine oil and filter change
- Fuel stabilization and filter replacement
- Air filter inspection and cleaning
- Alternator winding moisture protection
- Control panel and junction box sealing
- Exercise schedule setup for periodic running
Pump & Transmission Storage Prep
Industrial pumps, gearboxes, and hydraulic systems require specialized off-season protection.
- Pump casing drain and internal drying
- Seal and gasket preservation with silicone grease
- Transmission fluid drain and refill
- Clutch plate inspection and rust prevention
- Hydraulic system flush and filter change
- Shaft coupling protection and alignment lock
- Desiccant packs for enclosed gearboxes
📋 The Winterization Process
Pre-Inspection
Full engine health check — compression, oil analysis, coolant test, and fault code scan. We document baseline condition.
Fluid Changes
All fluids changed hot to suspend contaminants: engine oil, filters, gear oil, coolant, and fuel filters.
System Flush & Drain
Cooling systems flushed with freshwater, then drained or filled with marine-grade antifreeze (-37°C protection).
Fuel Treatment
Tank filled to 95% capacity with stabilized fuel. Biocide added for diesel. System run to circulate treated fuel.
Internal Protection
Cylinders fogged with corrosion inhibitor. Exhaust ports sealed. Intake filtered. Desiccant placed in engine bay.
Documentation
Winterization certificate issued with photos, fluid specs, and a spring commissioning checklist.
🌱 Spring Commissioning (De-Winterization)
Spring commissioning is not just "start the engine." Our de-winterization service reverses every winterization step and verifies all systems are ready for the season.
Outboard Spring Commissioning
Cooling system flush, new impeller installation, lower unit pressure test, fuel system purge, spark plug reinstallation, control cable lubrication, propeller reinstallation with new cotter pin, and sea trial with RPM and temperature verification.
Inboard Spring Commissioning
Cooling system refill and pressure test, raw-water pump impeller replacement, oil and filter change, fuel system bleed and leak check, exhaust system inspection, belt tension check, battery load test, shaft alignment verification, and sea trial with full parameter logging.
Generator Spring Commissioning
Coolant refill and cap pressure test, oil and filter change, air filter replacement, fuel system bleed, control panel function test, AC output voltage and frequency verification, load bank test, and exercise run under load.
Pump & Transmission Spring Prep
Seal and gasket inspection, transmission fluid refill, hydraulic system bleed and pressure test, coupling alignment check, and dry-run test before wet connection.
🏭 Storage Options
We offer secure, climate-controlled storage for engines, generators, and equipment at our Nieuwersluis facility. Ideal for customers without covered storage or those storing high-value equipment.
| Storage Type | Price / Month | Features | Best For |
|---|---|---|---|
| Indoor Heated Storage | €85 | Climate-controlled (15°C), humidity monitored, individual bay, insurance included | High-value outboards, classic engines, EFI systems |
| Indoor Unheated Storage | €55 | Dry, frost-free warehouse, pallet racking, security patrol | Standard outboards, transmissions, pumps |
| Covered Outdoor Storage | €35 | Roofed bay, breathable cover provided, wind-protected | Robust diesels, large generators, equipment on pallets |
| Engine Crate Storage | €45 | Sealed crate with desiccant, vibration-dampened pallet, quarterly inspection | Crate engines, spare engines, reconditioned units |
| Container Storage (Shared) | €25 | Shared 20ft container, individual compartment, padlock | Parts, accessories, smaller pumps |
💶 Winterization Pricing Guide
| Service | Starting From | Duration | Notes |
|---|---|---|---|
| Outboard Winterization (up to 30 HP) | €195 | 2 hours | Flush, fog, oil change, gear oil, grease |
| Outboard Winterization (30–90 HP) | €275 | 3 hours | Includes impeller inspection and fuel treatment |
| Outboard Winterization (90–300 HP) | €395 | 4 hours | Full EFI system flush, software check, cover |
| Inboard Diesel Winterization | €450 | 4–5 hours | Coolant drain/fill, oil, filters, fuel treatment |
| Twin Diesel Winterization | €750 | 6–8 hours | Both engines, genset, shared systems |
| Generator Winterization | €295 | 3 hours | Load test, coolant, oil, fuel, cover |
| Pump / Transmission Winterization | €180 | 2 hours | Drain, dry, preserve, crate if stored |
| Outboard Spring Commissioning | €225 | 3 hours | Reverse winterization, new impeller, sea trial |
| Inboard Spring Commissioning | €495 | 5–6 hours | Full system check, alignment, sea trial |
| Generator Spring Commissioning | €325 | 3–4 hours | Load bank test, voltage/frequency check |
| Winterization + Spring Combo | €395 | — | 10% discount when both booked together |
🔧 DIY vs. Professional Winterization
What You Can Do Yourself
Basic tasks like washing the engine, applying corrosion spray to external surfaces, and covering the unit with a breathable cover. These are cosmetic and do not protect internal systems. If you are mechanically experienced, you can change oil and drain cooling water — but improper drainage leaves pockets that freeze and crack castings.
What Requires a Professional
Fogging cylinders through spark plug holes (requires correct oil type and volume), pressure-testing the cooling system after refill, checking exhaust elbow integrity, verifying fuel system integrity, and documenting the service for warranty. EFI engines require software checks and fuel rail pressure bleed procedures that cannot be done without scan tools. Most manufacturer warranties require professional winterization documentation.
✅ Winterization Checklist
Whether you choose DIY or professional service, ensure every item below is completed before the first frost:
Outboard Checklist
- ☐ Freshwater flush completed
- ☐ Cooling system fully drained
- ☐ Fuel tank filled to 95%
- ☐ Fuel stabilizer added and circulated
- ☐ Engine oil changed (4-stroke)
- ☐ Lower unit oil drained and refilled
- ☐ Cylinders fogged, plugs reinstalled loose
- ☐ Water pump impeller inspected
- ☐ Grease applied to all pivot points
- ☐ Propeller removed and inspected
- ☐ Battery removed and on trickle charger
- ☐ Engine stored upright or per manual
- ☐ Breathable cover applied
Inboard Checklist
- ☐ Raw-water system flushed and drained
- ☐ Closed cooling drained or antifreeze filled
- ☐ Engine oil and filter changed
- ☐ Fuel filters replaced
- ☐ Fuel tank stabilized and biocide added
- ☐ Exhaust system drained
- ☐ Raw-water impeller removed
- ☐ Seacocks closed and tagged
- ☐ Intake and exhaust ports sealed
- ☐ Belts inspected and tension recorded
- ☐ Battery disconnected and trickle-charged
- ☐ Engine bay desiccant placed
- ☐ Winterization certificate issued
Book Your Winterization Today
Slots fill quickly from September through November. Book early to secure your preferred date and avoid the rush. Combine winterization + spring commissioning for 10% off.
Book Winterization Request a Quote