Quicksilver Rust Guard Rust Inhibitor 858081KC2 – 12 oz Spray
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Quicksilver Rust Guard Rust Inhibitor 858081KC2 – 12 oz Spray
Part Number: 858081KC2 (also listed as 92-858081KC2)
Brand: Quicksilver (Mercury Marine OEM)
Official Product Type: Rust Inhibitor / Storage Protection Spray
Size: 12 oz aerosol spray can
System: Engine Corrosion Protection & Storage
Condition: New OEM
Supersession Notice
Part number 858081KC2 has been superseded by 858081KC3 – Quicksilver Rust Guard Rust Inhibitor (current version). If you are ordering new stock, the KC3 is the current replacement. The KC2 may still be available while supplies last.
What It Does
Quicksilver Rust Guard is an OEM rust inhibitor spray designed to protect internal and external metal surfaces on marine engines during storage and winterization. It forms a protective barrier against moisture and corrosion, helping prevent rust from developing on engine components that sit idle for extended periods.
Compatible Applications
- Mercury and MerCruiser 2-stroke gasoline outboards
- Mercury and MerCruiser 4-stroke gasoline outboards
- MerCruiser sterndrive engines
- External metal surfaces, linkages, and hardware on marine engines
- General marine metal protection during lay-up
This is a maintenance chemical, not a model-specific hard part. Serial number confirmation is not required. Follow the storage procedure in your engine's owner's manual.
Service Interval
Apply once per storage season — at the start of winterization or before any extended lay-up of 30 days or more. Reapply as needed if the engine is stored in a high-humidity environment.
Supersedes / Related Part Numbers
- 858081KC2 — this listing (superseded)
- 92-858081KC2 — alternate prefix format, same part
- 858081KC3 — current replacement part (Quicksilver Rust Guard, updated version)
Kit Contents
Single 12 oz aerosol spray can. No additional components included.
Related Products
- Quicksilver Rust Guard Rust Inhibitor 12 oz – 858081KC3 (Current Version)
- Mercury Fogging Oil 858081K03 – 12 oz Storage Protection Spray
- Mercury Antifreeze –50°F, 1 Gallon – 8M0073201
Parts Desk Insights
Best Use Case: Rust Guard is ideal for protecting external metal surfaces, linkages, throttle cables, and exposed hardware during winter storage — areas that fogging oil doesn't reach. Use it alongside fogging oil and antifreeze for a complete winterization. It's also useful mid-season on boats stored in saltwater environments where corrosion accelerates quickly.
Common Mistakes: Customers sometimes confuse Rust Guard (KC2/KC3) with Fogging Oil (K03) — they serve different purposes. Fogging oil goes inside the engine cylinders; Rust Guard protects external surfaces. Don't substitute one for the other. Also note the supersession: if you're ordering for resale or future use, order the KC3 to avoid receiving discontinued stock.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.