Quick answer Boat winterization in Ontario is not a flat number, it depends on motor size, what services you bundle, and whether you are adding shrinkwrap and storage. Motor winterization is the most critical piece. Skipping it risks a cracked block, which costs several...
Quick answer
Boat winterization in Ontario is not a flat number, it depends on motor size, what services you bundle, and whether you are adding shrinkwrap and storage. Motor winterization is the most critical piece. Skipping it risks a cracked block, which costs several thousand dollars to repair or replace. Book before October to get the easier slots. Request service at hbw.wiki/service.
Winterization price summary (CAD)
| Service |
Price (CAD) |
| Fuel stabilizer + ethanol treatment |
$30 to $50 |
| Fogging oil through cylinders |
$50 to $80 |
| Lower unit oil change + inspection |
$50 to $90 |
| Cooling system flush + drain |
$40 to $70 |
| Battery prep |
$25 to $50 |
| Total typical all-in range |
$250 to $400 |
Prices are typical CAD ranges, HST extra. Final pricing depends on motor size and condition.
Where the money goes
What goes into a Mercury winterization quote?
A full marina winterization is usually 5 line items. Here is what each one covers and the typical CAD range.
Fuel stabilizer + ethanol treatment$30 - $50
Marine-grade stabilizer mixed into a near-full tank to prevent phase separation over winter
Fogging oil through cylinders$50 - $80
Mercury recommends fogging the intake while running, then a shot into each cylinder. Prevents cylinder wall corrosion.
Lower unit oil change + inspection$50 - $90
Old oil out, fresh oil in, magnetic plug checked. Milky oil here is the biggest fall finding we make.
Cooling system flush + drain$40 - $70
Run fresh water for 5 to 10 minutes on muffs, then tilt straight down to drain. Prevents block-freeze cracks.
Battery prep$25 - $50
Either pulled to indoor storage with a maintainer, or a tender installed on board. Cheap insurance.
Typical all-in range$250 - $400 CAD
Pricing varies by motor size, accessibility, and current shop rate. HST extra. Book a winterization slot at /service.
Why the price varies (and why flat rates mislead you)
A 9.9 HP tiller is a 90-minute job. A 250 HP V8 Verado is a 3-hour job with more oil capacity, more spark plugs, a more complex fuel system, and more lower unit to service. Same checklist, completely different amounts of time and parts.
When you see a "$549 winterization" posted on a marina website, that number was set for one boat configuration and applied to everything else. You are either paying for work that does not apply to your motor, or skipping work that should have happened. Neither is a good deal.
We quote winterization based on what is in front of us.
What changes your winterization cost
Motor size and type. A small tiller takes less time and fewer parts than a large V8. Bigger motors cost more to winterize, this is unavoidable.
Inboard/sterndrive vs outboard. A sterndrive (Mercruiser 4-cylinder, V6, V8) is a different job than an outboard. You are draining the block, the manifolds, and the raw-water lines; applying antifreeze to the right places; and servicing the gimbal bearing.
Bundled services. Motor-only winterization is the base. Add shrinkwrap, storage, trailer service, battery storage, and spring commissioning booking, the number grows.
What is included in the winterization scope. Basic winterization covers the freeze-protection essentials: fuel stabilizer, fogging, cooling system drain, gearcase drain and refill. A full service adds wear-item replacements, impeller, anodes, plugs if due, plus a full written inspection.
Motor condition and age. A clean, regularly serviced motor takes the expected time. A neglected motor takes more, and we will tell you what additional service is needed before we start.
Booking timing. September and early October bookings are easier to schedule. Late October and November are the crunch window. Booking early is usually the smarter and cheaper choice.
For an exact quote on your specific setup, request service at hbw.wiki/service.
What winterization actually includes at HBW
Every motor we winterize at HBW gets the same procedure. Time and parts vary by engine size; the checklist does not:
Engine flush. 10 to 15 minutes on muffs with fresh water to clear lake water, silt, and debris from the cooling system.
Fuel stabilizer. Mercury Quickstor added to the fuel, engine run to circulate it through the entire fuel system including injectors or carbs.
Fogging. Cylinders fogged with Mercury Storage Seal until the engine smokes and stalls. Partial fogging means partial protection.
Spark plugs. Removed, cylinders fogged individually, reinstalled or replaced if they are due.
Oil change. Full crankcase oil and filter, drained while warm so the used oil evacuates completely.
Gearcase service. Lower unit drained, inspected for water intrusion (milky oil means a seal failure we want to know about before it freezes), refilled with Mercury High Performance gear oil.
Cooling system drain. All water removed from the block, water passages, and tell-tale. This is the step that prevents freeze damage. Miss it, and Ontario temperatures will find it.
Battery service. Charged, terminals cleaned, removed from the boat, and stored on a smart charger in a building that stays above freezing.
Full written inspection. Any service work identified during winterization is documented and communicated before spring.
Optional add-ons available separately or as a package:
- Shrinkwrap the hull for outdoor storage
- Trailer bearing service
- Bilge clean-out
- Pre-booked spring commissioning
Storage options at HBW
We offer outdoor winter storage at HBW with shrinkwrap. We do not offer indoor heated storage. For indoor heated, we will point you to the right options in the region rather than pretend we have it.
You can build a live CAD quote for your repower online at Mercury Repower Centre.
Outdoor storage with shrinkwrap is the practical answer for most Rice Lake and Kawartha boats: aluminum fishing boats, pontoons, runabouts. For high-end fibreglass cruisers with custom paint, indoor might be worth the premium at another shop. Choose based on your boat, not based on what makes the marina more money.
Contact us for current per-foot rates. Note that the marina is closed during winter months, but we are available by phone, text, or email anytime, so storage drop-off windows close in late fall and pickups resume in early April. Harris Boat Works is drop-off only: customers bring the boat to our Gores Landing marina, we do not offer pickup or delivery service.
Shrinkwrap: separate from winterization
Shrinkwrap and winterization are two different jobs:
Shrinkwrap keeps snow, ice, and wildlife out of the boat. It does not protect the engine from freezing.
Winterization protects the engine. Without it, the wrap is just keeping snow off a boat that is freezing from the inside.
Customers who do their own winterization (or have it done elsewhere) sometimes just want shrinkwrap. We accommodate that, you can drop off, get wrapped, and tow the boat home or to cottage storage.
At HBW, shrinkwrap is priced per foot. In-shop wrap costs less because it is climate-controlled, no wind, faster work, tighter seams. Outdoor wrap costs slightly more.
DIY vs professional winterization
Winterization is one of the service jobs a confident, experienced boater can handle DIY.
DIY makes sense when:
- You have done it before and know the process
- The motor is smaller (under 60 HP) and accessible
- You have a clean indoor space
- You have the right supplies (gear lube pump, fogging oil, fuel stabilizer, fresh oil and filter)
- You are willing to own the outcome if you miss a step
Bring it to us when:
- The motor is larger (90 HP and up) and harder to access
- You have not done it before
- The boat lives outside and freeze protection is critical
- You are not sure last year winterization was complete
- You want spring commissioning bundled so the boat is launch-ready in May
The two most expensive DIY mistakes we see in spring:
Customer drained the gearcase but forgot to refill it. Motor runs without lower-unit lube. Gears destroy themselves in 30 minutes. Lower unit replacement: $1,500 to $4,500 CAD depending on the motor.
Customer missed the cooling system drain. Water freezes in the powerhead. Block cracks. Motor is scrap. We see this every single spring on boats where someone partially DIY'd the winterization.
Both are avoidable.
Spring commissioning: book it in fall
Spring commissioning is the inverse of winterization, and booking it in fall is almost always the right call.
What spring commissioning includes at HBW:
- Gearcase lube refill
- Battery reinstall and load test
- Fuel system check and filter replacement if due
- Cooling system flush
- Visual inspection
- Test run on muffs or in the water
- Hull and trailer launch prep
Why book in fall: Spring service backlog is real. If you call in April and ask for a May launch date, you may wait. If you pre-booked commissioning in October when you dropped the boat off, your slot is already locked.
We winterized 584 boats last fall
In August through November 2025, Harris Boat Works completed 584 winterizations across Rice Lake and the Kawarthas. That volume matters because it means the procedure is routine for our team, the appointment scheduling is dialed in, and we have seen the full range of what Ontario winters do to motors that were not properly prepped.
We would rather you call us in September than call us in May about a cracked block.
Book winterization
Request winterization, shrinkwrap, storage, or the full package at hbw.wiki/service. We start scheduling in late September. Booking early gets you the better slot.
Or call 905-342-2153.
Last reviewed: 2026-05-11.
For broader context on storage options across the Kawarthas, see our Kawartha Lakes boat storage guide.
Ready to price it out? Build a live CAD quote for your repower online at the Mercury Repower Centre.
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