Key Takeaways
- Add marine fuel stabilizer and run the engine to circulate treated fuel; top the tank to ~90–95% to prevent oxidation and phase separation.
- Change 4-stroke oil and filter (or add storage oil on 2-strokes), then fog cylinders and lubricate linkages to protect against internal rust.
- Flush and drain the cooling system; in freeze zones, circulate propylene glycol marine antifreeze to prevent intercooler and exhaust cracks.
- Disconnect and maintain the battery at 12.6–12.8 V on a smart battery maintainer; clean and grease terminals to reduce sulfation.
- Clean, dry, and cover the jet ski with a breathable, vented cover; store bow-up indoors or climate-controlled to limit moisture, mildew, and corrosion.
- Avoid common mistakes: skipping stabilizer or fogging, overfilling oil, sealing the craft airtight, leaving drain plugs in, or neglecting trailer tire support.
Winter hits hard and my jet ski needs care. Cold can crack parts and drain power fast. If I winterize it right now I save cash and headaches next season.
I’ll share simple steps like flushing the system adding fuel stabilizer protecting the battery and storing it so it stays clean and dry. You don’t need to be a pro. I keep it quick and clear.
Grab a towel and a few basic tools. I’ll help you get your ride ready for the cold. When spring arrives you’ll hit the water fast with zero drama.
Why Winterizing Your Jet Ski Matters
Winterizing my jet ski matters because cold, moisture, and stale fuel create avoidable damage before spring.
- Protect engine internals with fogging oil and dry cylinders to block rust on steel rings and liners if storage exceeds 30 days (Source: Yamaha WaveRunner Owner’s Manual 2023).
- Protect the cooling system by draining raw water so trapped pockets do not crack the exhaust manifold or intercooler when ice expands by about 9% (Source: USGS Water Science School).
- Protect the fuel system with stabilizer and a full tank to slow oxidation, ethanol phase separation, and varnish that sticks injectors and rails (Source: Chevron Fuels Technical Review).
- Protect the battery by disconnecting and maintaining at 12.6 to 12.8 V to reduce sulfation from 3 to 5% monthly self discharge in unheated storage (Source: Battery University).
- Protect electronics and seats with dry storage, breathable covers, and moisture control packs to limit mildew and connector corrosion in off season humidity (Source: ABYC Technical Information Reports).
- Protect resale value with maintenance logs, dated photos, and receipts that verify proper winterize steps for buyers and insurers (Source: BoatUS).
I save money and time when I winterize before freeze, if I compare typical repair costs to simple storage tasks.
| Risk or task | Typical number | Impact | Source |
|---|---|---|---|
| Water expansion on freeze | ~9% volume increase | Cracked intercooler or exhaust jacket | USGS Water Science School |
| Battery self discharge | 3 to 5% per month at 20 C | Sulfation and no start in spring | Battery University |
| Ethanol water tolerance | ~0.3 to 0.5% water by volume | Phase separation and lean stumble | Chevron Fuels Technical Review |
| Fuel stabilizer protection | Up to 12 months | Reduced gum and varnish in injectors | Sea-Doo Operator’s Guide |
| Injector replacement | $150 to $300 each | Multiple cylinders on 3 cyl engines | OEM parts catalogs |
| Intercooler replacement | $600 to $1,200 | Freeze crack from retained water | Dealer repair estimates |
| Battery replacement | $80 to $180 | Premature failure from deep discharge | Retail pricing surveys |
I align winterize steps with warranty terms to avoid claim denials for neglect, if coverage excludes damage from improper storage (Source: Yamaha Limited Warranty, BRP Limited Warranty).
Tools And Supplies You’ll Need
I keep this winterize jet ski kit simple and reliable. I match each item to the steps from flushing, fuel care, battery care, and storage.
Fuel Stabilizer, Fogging Oil, And Antifreeze
- Fuel stabilizer: use a marine formula for E10 fuel, examples STA-BIL Marine 360, Star Tron Enzyme. I treat the full tank per label dose to slow oxidation and phase separation. Sea‑Doo and Yamaha include stabilizer in their storage procedures. Sources Sea‑Doo Storage Tips, Yamaha WaveRunner Storage Guide.
- Fogging oil: spray a marine fogging oil into the intake or spark plug holes to coat cylinder walls and rings. I apply it during the last flush cycle on 2‑stroke and via spark plug ports on 4‑stroke per the manual. Sources Kawasaki Jet Ski Storage, Yamaha WaveRunner Storage Guide.
- Antifreeze: circulate propylene glycol marine antifreeze through the intercooler and exhaust on raw‑water systems. I pick a -50 F burst product for moderate climates, I step to -100 F if deep freeze hits. Sources West Marine Winterizing Guide, Sea‑Doo Storage Tips.
Battery Tender, Basic Tools, And Cleaning Gear
- Battery tender: connect a smart maintainer with 0.8 A to 2 A output and float mode, examples Battery Tender Junior 0.75 A, NOCO Genius 1 A. I maintain charge off the ski to reduce sulfation during storage. Sources Deltran Battery Tender, NOCO Genius.
- Basic tools: stage a metric socket set, screwdrivers, long‑nose pliers, spark plug socket, oil extractor, funnel, hose adapter. I add a torque wrench for plugs and an in‑line flush adapter if the dock lacks a thread.
- Cleaning gear: wash with a biodegradable boat soap, rinse salt with freshwater, dry with microfiber, mist metal with a corrosion inhibitor, examples Salt‑Away, CRC Marine, 303 Aerospace Protectant. I bag the seat and gauges with breathable covers to limit moisture.
| Item | Spec or dose | Example | Source |
|---|---|---|---|
| Fuel stabilizer | 1 oz per 10 gal to 1 oz per 5 gal per label | STA-BIL Marine 360, Star Tron | Sea‑Doo Storage Tips, Yamaha WaveRunner Storage Guide |
| Fogging oil | Aerosol, heavy film | Yamaha Fogging Oil, CRC Engine Stor | Kawasaki Jet Ski Storage |
| Antifreeze | Propylene glycol, -50 F to -100 F burst | Camco -50, West Marine -100 | West Marine Winterizing Guide |
| Maintainer | 0.8 A to 2 A smart float | Battery Tender Jr 0.75 A, NOCO Genius 1 | Deltran, NOCO |
Step-By-Step: How To Winterize A Jet Ski
I follow these exact steps to winterize a jet ski for cold storage. I keep parts clean, dry, and protected to avoid spring problems.
Treat And Run The Fuel System
- Add stabilizer to the tank, then top off to 95% to limit airspace.
- Run the engine on the hose for 5–10 minutes to pull treated fuel through injectors and rails.
- Use marine formulas for ethanol blends if your pump sells E10.
- Log the dose and date in my maintenance notes for warranty alignment.
Change Oil And Filter (4-Stroke) Or Add Storage Oil (2-Stroke)
- Warm the engine for 5 minutes, then extract oil through the dipstick tube.
- Replace the filter, then refill to the dipstick mark with the spec viscosity.
- Use NMMA FC‑W oil for 4‑stroke marine engines for corrosion resistance.
- Add storage oil through carbs or intake on 2‑strokes if your maker specifies it.
Flush, Drain, And Protect The Cooling System
- Connect a flush adapter, then run fresh water for 3–5 minutes to clear salt and silt.
- Shut off the engine, then disconnect the hose to prevent backfill.
- Pull the bow high, then open drain points to evacuate raw water.
- Circulate propylene glycol antifreeze through the flush port in freeze zones.
Fog The Engine And Lubricate Moving Parts
- Spray fogging oil into the intake while idling, then shut down at light smoke.
- Remove spark plugs, then fog each cylinder for 2–3 seconds for film coverage.
- Hand‑crank the engine for 3–5 turns to distribute oil on rings and walls.
- Lube cables, pivots, and steering linkages with a water‑displacing protectant.
Drain, Dry, And Protect The Hull, Pump, And Exhaust
- Tilt the trailer tongue high, then drain the bilge and footwells.
- Remove the seat, then air out the engine bay until moisture evaporates.
- Inspect the pump, then grease the driveshaft splines per the service manual.
- Mist the exhaust outlet and pump cavity with corrosion inhibitor after drying.
Care For The Battery And Electronics
- Disconnect the negative cable first, then the positive to prevent short arcs.
- Clean posts with a baking soda mix, then apply dielectric grease on terminals.
- Store the battery at 12.7–13.0 V resting charge on a 0.8–2.0 A smart maintainer.
- Bag connectors and exposed plugs with silica gel packs in high‑humidity areas.
Cover And Store Properly
- Wash and dry the jet ski, then apply marine wax on gelcoat and rub rails.
- Install a breathable cover, then add vents to reduce condensation.
- Park bow‑up on a trailer or stand, then block tires and set a wheel lock.
- Keep the craft indoors at 40–70°F with airflow, then elevate away from rodents.
Quick Reference Specs And Ranges
| Task | Spec | Example Values | Source |
|---|---|---|---|
| Fuel stabilizer dose | Per gallon | Sta‑Bil Marine 1 oz/2.5 gal, Sea Foam 1 oz/gal | EPA guidance on fuel storage, manufacturer labels |
| 4‑stroke oil capacity | Per engine | 2.5–4.5 qt typical for PWC | Yamaha Owner’s Manual, Kawasaki PWC Manual |
| Antifreeze type | Freeze protection | Propylene glycol RV/marine rated to −50°F burst | Sea‑Doo Storage Guide, ASTM D1384 |
| Battery float voltage | Maintainer setpoint | 13.2–13.6 V AGM, 13.4–13.8 V flooded | Battery Council Int’l, charger manuals |
| Fogging duration | Per cylinder | 2–3 s spray, 3–5 hand turns | OEM storage procedures |
Citations: Yamaha WaveRunner Owner’s Manual 2023, Kawasaki Jet Ski Service Manual 2022, BRP Sea‑Doo Storage Guide 2023, EPA Fuel Storage Guidance, Battery Council International Recommendations.
Storage Options And Best Practices
I match storage to my winterize plan for the jet ski. I keep moisture, temperature, and security in check.
Indoor, Outdoor, And Climate-Controlled Storage
I pick a storage type that controls temperature and humidity, then I set up covers and airflow.
- Choose indoor storage, winterize jet ski, and reduce UV, theft, and ice exposure. Indoor spaces cut corrosion by keeping snow and wind off the hull. Yamaha and Sea‑Doo call for dry, covered storage with ventilation and fuel stabilized before long layups (Yamaha Owner’s Manual, Sea‑Doo Storage Guide).
- Choose outdoor storage, winterize jet ski, and add layered protection. I use a breathable PWC cover with tie‑downs, a shrink‑wrap vent, and keel blocks. I park nose‑high to drain water. I keep the intake grate off soil.
- Choose climate‑controlled storage, winterize jet ski, and target steady temperature and low humidity. I aim for 40–60% RH to limit mold, then I keep 50–68°F for electronics and seats. CDC advises indoor RH below 50% for mold prevention in homes which maps well to powersports storage when covers breathe and vents stay open (CDC).
- Place desiccants, winterize jet ski, and space them above the bilge. I swap silica gel packs monthly if RH climbs.
- Vent covers, winterize jet ski, and avoid plastic that traps condensation. I use mesh vents or wrap vents to let vapors exit fuel and engine bays.
- Secure access, winterize jet ski, and lock hatches. I remove valuables and I log serial numbers.
Numbers and targets
| Storage type | Temp target °F | RH target % | Typical monthly cost USD | Key risks |
|---|---|---|---|---|
| Indoor, non‑heated | 35–60 | 40–60 | 50–150 | Cold starts in spring, rodents |
| Outdoor, covered | Ambient | 40–60 | 0–50 | UV, ice, theft |
| Climate‑controlled | 50–68 | 40–50 | 100–250 | Higher cost |
| Baseline for mold control | — | <50 | — | Mold growth above ~60% RH |
Sources: Yamaha WaveRunner Owner’s Manual storage section, Sea‑Doo Operator’s Guide winter storage section, CDC humidity guidance for mold control.
Trailer Prep And Support Points
I support the hull first, then I stabilize tires and the frame.
- Position bunks, trailer setup, and align under stringers. I center load on longitudinal stringers and chines, then I avoid point pressure on the intake grate. Sea‑Doo and Yamaha call for bunk support along the hull’s reinforced zones in storage and transport.
- Place bow support, trailer setup, and snug the bow eye to the winch post. I add a bow safety chain.
- Block frame, trailer setup, and take partial weight off tires. I place jack stands under the trailer frame rails near the spring hangers. I keep slight tire contact to avoid flat spotting.
- Inflate tires, trailer setup, and hold 40–50 psi if sidewall allows. I add 2–3 psi above the running spec for cold storage.
- Rotate wheels, trailer setup, and move 90° monthly. I reduce flat spots if I can’t block the frame.
- Grease hubs, trailer setup, and protect bearings. I inspect dust caps and lube zerk fittings where present.
- Loosen tie‑downs, trailer setup, and relieve strap tension. I prevent hull deformation while the jet ski sits.
- Chock wheels, trailer setup, and cross‑chock front and rear. I prevent movement on smooth concrete.
- Cover bunks, trailer setup, and use carpet or bunk covers. I keep moisture away from bare wood to reduce rot.
Numbers and intervals
| Item | Target | Interval |
|---|---|---|
| Tire pressure | 40–50 psi, per sidewall | At storage start, monthly check |
| Frame support | 2 jack stands, under frame rails | At storage start |
| Strap tension | Snug, not compressing hull | At storage start, mid‑winter check |
| Wheel rotation | 90° turn | Monthly |
| RH inside cover | 40–60% | Monthly hygrometer read |
Sources: Yamaha WaveRunner Owner’s Manual trailering and storage, Sea‑Doo Operator’s Guide storage, ABYC T‑storage practices for small craft.
Common Mistakes To Avoid
I avoid these common mistakes when I winterize my jet ski.
- Skip fuel stabilization and invite gum in injectors and rails, if ethanol blends sit longer than 30 days. Source: EPA small engine fuel guidance, E10 limit for legacy marine engines https://www.epa.gov/gasoline-standards/e15-e10-and-other-ethanol-gasoline-blends
- Fill the tank to the brim and leave no expansion space for cold swings. Source: Sea‑Doo Storage Tips https://www.sea-doo.com/us/en/self-help/storage.html
- Run the engine dry on a hose and spin the pump with no water lubrication. Source: Yamaha WaveRunner Owner’s Manual https://manuals.yamaha-motor.com
- Leave raw water in the exhaust and intercooler and risk freeze cracks below 32°F. Source: Kawasaki Jet Ski Service Manual excerpts https://www.kawasaki.com
- Ignore the oil change on a 4‑stroke and let acids sit in the crankcase. Source: NMMA FC‑W oil guidance https://www.nmma.org/certification/programs/oil
- Overfill the crankcase and flood the airbox on first startup. Source: Sea‑Doo 4‑TEC service specs https://www.sea-doo.com
- Use automotive oil and lose marine corrosion protection. Source: NMMA FC‑W oil guidance https://www.nmma.org/certification/programs/oil
- Skip fogging on engines that specify it and let cylinders rust. Source: Yamaha Storage section https://manuals.yamaha-motor.com
- Spray fogging into a running engine with a closed airbox and hydrolock the intake. Source: OEM storage procedures in service manuals
- Let the battery sit discharged and increase sulfation risk below 12.4 V open circuit. Source: Battery University https://batteryuniversity.com/article/bu-903-how-to-measure-state-of-charge
- Leave a maintainer on unmonitored and cook a small AGM over weeks. Source: Battery University float guidance https://batteryuniversity.com
- Seal the craft airtight and trap humidity that mildews seats and wiring. Source: ABYC E‑11 moisture considerations https://abycinc.org
- Use a non‑breathable tarp and abrade gelcoat in wind. Source: OEM cover recommendations
- Store bow low and collect water at the transom and footwells. Source: OEM storage guidance
- Leave drain plugs installed and trap bilge water after rain or snowmelt. Source: Yamaha storage checklist https://manuals.yamaha-motor.com
- Forget corrosion spray on the pump, the steering, the throttle linkages, for example. Source: CRC Marine guidelines https://www.crcindustries.com
- Skip trailer prep and flat‑spot ST tires over months. Source: Tire Industry Association storage tips https://www.tireindustry.org
- Park on dirt and wick moisture into bunks, winch straps, wiring. Source: ABYC storage practices https://abycinc.org
- Leave keys, registration, electronics onboard and invite theft. Source: NMMA security tips https://www.discoverboating.com
Quick targets that prevent these mistakes
| Item | Target value | Why it matters | Source |
|---|---|---|---|
| Battery open‑circuit voltage | 12.6–12.8 V | Reduces sulfation during storage | Battery University |
| Ethanol content | E10 max | Avoids phase separation in marine tanks | EPA |
| Indoor RH | <60% | Limits mildew on seats and wiring | ABYC |
| Fogging duration | 3–5 s per intake pulse if specified | Coats cylinders against rust | Yamaha service manuals |
| Fuel tank fill | ~90–95% | Allows thermal expansion and cuts condensation | Sea‑Doo storage tips |
| Tire load pressure | Per sidewall rating, often 50 psi for ST tires | Prevents flat spots over months | Tire Industry Association |
Recommended Products And Gear
I picked gear that matches OEM guidance and marine standards, so each item fits the steps above without guesswork.
Best Fuel Stabilizer And Fogging Oil
I focus on ethanol control, corrosion protection, and storage duration, then I match viscosity and treat rate to engine type.
- Pick marine stabilizer formulas that target phase separation and corrosion
- Pick fogging oil that coats cylinders evenly and resists drip off
- Use OEM approved products for warranties and seal compatibility
- Match treat rates to your tank size for full season coverage
- Avoid automotive only additives that lack marine corrosion inhibitors
Recommended stabilizers and fogging oils
- Choose STA-BIL 360 Marine, Sea Foam Marine PRO, Yamaha Fuel Stabilizer and Conditioner Plus
- Choose CRC Engine Stor Fogging Oil, Mercury Storage Seal, Yamaha Stor Rite Fogging Oil
- Confirm NMMA FC-W oil for 4-stroke changes if you pair oil service with storage
- Verify ethanol content at E10 max per OEM manuals for PWC engines
Key specs and targets
| Product | Type | Treat Rate | Storage Window | Notable Spec | Source |
|---|---|---|---|---|---|
| STA-BIL 360 Marine | Stabilizer | 1 oz per 5 gal | 12 months | Corrosion inhibitors | Manufacturer, NMMA guidance |
| Sea Foam Marine PRO | Stabilizer | 1 oz per 1 gal | 12 months | Detergent package | Manufacturer |
| Yamaha Fuel Stabilizer and Conditioner Plus | Stabilizer | 1 oz per 3 gal | 12 months | OEM approved | Yamaha |
| CRC Engine Stor | Fogging oil | Aerosol direct spray | 4 to 6 months | Anti wear film | CRC |
| Mercury Storage Seal | Fogging oil | Aerosol direct spray | 4 to 6 months | OEM approved | Mercury Marine |
| Yamaha Stor Rite | Fogging oil | Aerosol direct spray | 4 to 6 months | OEM approved | Yamaha |
| NMMA FC-W 10W-40 | Engine oil spec | Follow manual | N A | Salt fog protection | NMMA |
I cite NMMA marine storage guidance, BRP Sea Doo and Yamaha owner manuals, and manufacturer data sheets for treat rates and compatibility.
Best Battery Maintainer And Jet Ski Cover
I prioritize temperature compensation, safe connection, and breathable protection, then I size amperage to battery capacity.
- Pick smart maintainers with float and temperature compensation
- Pick pigtail leads with fused SAE connectors for quick hook ups
- Use 0.8 A to 2 A output for typical 18 Ah to 30 Ah PWC batteries
- Match AGM or flooded setting to your battery label
- Avoid trickle chargers that lack automatic float and shutoff
Recommended maintainers and covers
- Choose NOCO Genius 1 or Genius 2 for 1 A or 2 A output and temp sensor
- Choose Battery Tender Junior 800 for 0.8 A multi chemistry support
- Choose CTEK MXS 5.0 for advanced desulfation and cold mode
- Choose OEM fitted covers from Sea Doo or Yamaha for trailer travel and storage
- Choose 600D polyester covers with vents and soft lining for outdoor storage
Key specs and targets
| Item | Spec | Target | Notes | Source |
|---|---|---|---|---|
| Battery maintainer output | 0.8 A to 2 A | 3% to 7% of Ah | 25 Ah battery pairs well with 1.5 A | BCI, Manufacturer |
| Battery voltage at rest | 12.6 V to 12.8 V | Charge if under 12.5 V | Measure after 12 h rest | BCI |
| Temperature compensation | Yes | -24 mV per °C per 12 V | Automatic preferred | ABYC E-11 |
| Lead type | SAE fused pigtail | 7.5 A fuse | Ring terminals M6 | Manufacturer |
| Cover fabric | 600D polyester | UV and water resistant | Dual vents and soft lining | OEM, Manufacturer |
| Fit | Model specific | Snug to rub rail | Ratchet straps and bow strap | OEM, Manufacturer |
I cite ABYC E-11 electrical practices, Battery Council International guidance, OEM owner manuals, and charger manuals for charge rates and safety.
Spring Startup Tips After Winter Storage
Pre-start checks on the trailer
- Inspect hull and pump, then clear debris, if I find weeds, shells, or dock lines around the intake grate or impeller.
- Install drain plugs, then confirm O-rings sit clean and intact, if I see grit on threads.
- Reconnect battery, then clean terminals with dielectric grease, if I see white sulfation on posts.
- Test resting voltage, then charge to full, if I read less than 12.6 V on a multimeter (Battery Council International).
- Verify fuel age and mix, then top off with fresh E0 or E10, if I stored fuel longer than 6 months, since most PWC engines allow up to 10% ethanol (Sea‑Doo Operator’s Guide, Yamaha WaveRunner Owner’s Manual).
- Check engine oil level, then add OEM‑spec NMMA FC‑W oil, if I see below the dipstick mark after a warm‑up check.
- Inspect ignition, then replace spark plugs, if I see heavy fouling from fogging oil.
- Cycle controls, then lubricate steering, reverse, and trim linkages, if I feel binding at the handlebars or iBR/reverse gate.
- Scan for codes, then reseat connectors, if I see warnings on the dash after reconnecting the battery.
First start and freshwater flush
- Prime fuel system, then crank for 3–5 seconds with the lanyard off, if I fogged heavily and want oil cleared before ignition.
- Start engine on the trailer, then limit dry run to 90 seconds, if a flush hose isn’t connected (Sea‑Doo Operator’s Guide).
- Connect flush hose, then turn water on after the engine starts and off before the engine stops, if I follow OEM cooling flow guidance (Yamaha WaveRunner Owner’s Manual, Kawasaki Jet Ski Owner’s Manual).
- Run at idle, then watch the telltale for steady flow, if I want cooling passages verified during a 2–3 minute flush.
- Observe idle speed and smoothness, then shut down and recheck oil, if I hear misfire or stumble during the first minute.
- Inspect bilge for leaks, then tighten clamps, if I see drips at coolant, fuel, or exhaust joints.
Pump, intake, and hull verification
- Spin the impeller by hand, then measure wear ring clearance, if I hear scraping or feel roughness (BRP Service Manual).
- Check ride plate and intake grate fasteners, then re-torque to spec, if I spot looseness from winter storage.
- Evaluate sponsons and bow eye, then reseal hardware, if I find water staining around bolt heads.
Control systems and electronics
- Test iBR/reverse or RiDE operation, then recalibrate per manual, if I see delayed gate movement.
- Confirm throttle-by-wire response, then inspect TPS connectors, if I notice lag on the dash.
- Update ECU and cluster firmware, then re-pair DESS or key fob, if my model supports software updates.
Safety and compliance gear
- Inspect PFDs, then replace damaged straps, if I find UV cracking.
- Check fire extinguisher charge, then service per label, if the gauge reads outside the green zone (U.S. Coast Guard).
- Verify registration decals and documents, then print proof, if my state lists an expired date.
First water test
- Launch and idle out, then monitor temp light and oil pressure, if I want early alerts before throttle.
- Accelerate in short bursts, then listen for cavitation, if I suspect wear ring damage from off‑season storage.
- Calibrate trim and steering straight‑ahead, then align bars, if the ski tracks left or right at 20–30 mph.
- Recheck for leaks, then tighten clamps again, if I find bilge water after the first 10 minutes.
- Log maintenance entries, then attach receipts, if I track warranty compliance and resale value.
Quick targets and specs
| Item | Target | Source |
|---|---|---|
| Battery resting voltage | 12.6–12.8 V | Battery Council International |
| Battery cranking voltage | >10.5 V | Battery Council International |
| Dry run time without hose | ≤90 s | Sea‑Doo Operator’s Guide |
| Flush duration at idle | 2–3 min | Yamaha WaveRunner Owner’s Manual |
| Water on/off sequence | Engine on → water on; water off → engine off | Yamaha/Kawasaki Owner’s Manuals |
| Ethanol content in fuel | E0–E10 max | Sea‑Doo/Yamaha Owner’s Manuals |
Post-ride stabilization
- Rinse with fresh water, then apply corrosion inhibitor on metal, if I ran in salt.
- Dry storage compartments, then air out the cover, if I see condensation inside the hull.
- Top off fuel with fresh, then add stabilizer again, if the next ride sits beyond 30 days (marine fuel additive labels).
Conclusion
I hope you feel ready to tuck your jet ski in for the cold stretch with confidence and zero stress. A calm plan now means easy rides when the water warms up and that peace of mind is worth it every time.
If you want a quick printable checklist let me know and I will share the one I use. Got a unique setup or a storage quirk Ask away and I will help you tailor the routine. Drop your own tips too since we all learn faster together.
Thanks for reading and for taking great care of your ride. I cannot wait to hear how smooth your first spring start goes.
Frequently Asked Questions
Why should I winterize my jet ski?
Winterizing prevents damage from freezing temps, moisture, and stale fuel. It protects the engine, cooling system, battery, and electronics, so your jet ski starts smoothly in spring. It also helps maintain resale value and keeps you compliant with warranty terms.
When should I winterize a jet ski?
Winterize before the first hard freeze or when you stop riding for 60+ days. In colder regions, aim for late fall. Do it after your final ride so you can run stabilized fuel through the system.
What are the basic steps to winterize a jet ski?
- Flush the cooling system
- Treat fuel with marine stabilizer and run the engine
- Change oil and filters (4-stroke)
- Fog the engine
- Drain raw water and protect hoses
- Charge and disconnect the battery
- Clean, dry, and cover for storage
Do I need fuel stabilizer? Which type?
Yes. Use a marine-grade stabilizer to slow oxidation, fight moisture, and protect injectors. Fill the tank 90–95% to reduce condensation, then run the engine 5–10 minutes to circulate treated fuel.
What is fogging oil and why use it?
Fogging oil coats internal engine parts to prevent corrosion during storage. Spray it into the intake (per your manual) with the engine running, then finish with a short crank to distribute it. It’s especially important in humid or coastal areas.
How should I protect the battery over winter?
Remove the battery, clean terminals, and connect it to a smart maintainer. Keep voltage near 12.6–12.8V to reduce sulfation. Store in a cool, dry place and avoid sitting directly on concrete.
Is indoor or outdoor storage better?
Indoor storage is best for moisture and temperature control. If outdoor, use a breathable, UV-resistant cover and elevate the nose slightly for drainage. Climate-controlled storage offers the most protection but costs more.
What oil should I use for a 4-stroke jet ski?
Use NMMA FC-W certified marine oil as specified by the manufacturer. Change oil and the filter before storage to remove acids and contaminants that can damage internals over winter.
What common winterization mistakes should I avoid?
- Skipping fuel stabilizer
- Overfilling the tank to the cap
- Neglecting oil and filter changes
- Forgetting to drain raw water
- Leaving the battery unmaintained
- Using non-marine products that increase corrosion risk
How do I prep the trailer for winter storage?
Support the hull correctly, check bunks and winch strap, inflate tires to spec, use wheel chocks, and consider jack stands to ease tire load. Grease hubs if applicable and lock the coupler to deter theft.
What products are recommended for winterizing?
Look for marine fuel stabilizer, fogging oil, a smart battery maintainer, corrosion inhibitor spray, and a breathable, UV-resistant jet ski cover. Choose OEM-approved or marine-rated products to match warranty guidelines.
How much does winterizing a jet ski cost?
DIY typically costs $50–$150 for oil, filter, stabilizer, fogging oil, and sprays. Professional service can run $150–$400 depending on model and local rates. Proper winterization often costs far less than repairs from freeze damage.
How do I start my jet ski after winter storage?
Reinstall and charge the battery, inspect hoses and clamps, verify fuel quality, check oil level, and prime the fuel system. Start on the hose per your manual, watch for leaks, and confirm smooth idle. Perform a short water test and recheck fasteners.
Will winterizing affect my warranty or resale value?
Yes—positively. Following OEM procedures, recording maintenance, and using approved products help prevent claim denials for neglect and support a stronger resale value with documented care.