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Mercury Premium TC-W3 2-Stroke Oil 1 Litre 858021KC1

Original price $22.33 - Original price $22.33
Original price
$22.33
$22.33 - $22.33
Current price $22.33
Availability:
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Mercury Premium TC-W3 2-Stroke Oil — 1 Litre — 858021KC1

Part Number 858021KC1  |  Mercury Catalog: 92-858021KC1
Brand Mercury Marine / Quicksilver
Official Product Type Premium TC-W3 2-Stroke Marine Engine Oil
System 2-Stroke Engine Lubrication
Size 1 litre / 1.06 US qt
Specification NMMA TC-W3 certified
Format Canadian 1-litre bottle
Supersedes 831226A12 / 92-831226A12

Compatible Applications

Mercury specifies this oil for 2-stroke engines requiring NMMA TC-W3 lubricant. Always confirm the required oil specification in your engine owner’s manual before use.

  • Mercury 2-stroke outboards — carbureted and conventional models
  • Mariner 2-stroke outboards requiring TC-W3 oil
  • Force 2-stroke outboards (where TC-W3 is specified)
  • Mercury Sport Jet applications (where TC-W3 is specified)
  • Oil-injection systems where the owner’s manual specifies Premium TC-W3 oil
  • Premix applications at the fuel/oil ratio specified by the engine manufacturer
  • Other water-cooled 2-stroke equipment where TC-W3 is specifically permitted

Not for use in: engines requiring Mercury Premium Plus, OptiMax / DFI-specific oil, full-synthetic PWC oil, 4-stroke crankcase oil, or gear lubricant. Higher-output, direct-injected, or severe-duty engines may require a different Mercury lubricant — confirm in your owner’s manual.

Superseded / Cross-Reference Part Numbers

  • 858021KC1 (primary — Canadian 1-litre)
  • 92-858021KC1 (Mercury catalog format)
  • 831226A12 / 92-831226A12 (earlier 1-litre reference, superseded by 858021KC1)
  • 858021K01 / 92-858021K01 (related U.S. 1-quart package reference)

When to Use This Oil

  • Topping up a compatible engine-mounted or remote 2-stroke oil reservoir
  • Preparing a gasoline/oil premix at the ratio specified in the engine owner’s manual
  • Seasonal recommissioning of a compatible 2-stroke outboard
  • Replacing old, contaminated, or unknown oil with the correct TC-W3 product

Application Notes

For oil-injected engines: Fill the correct oil reservoir only. Keep the filler area clean to prevent dirt or water from entering the system. Do not mix unknown oil types unless the service manual specifically allows it.

For premix engines:

  • Use fresh gasoline of the grade specified in the owner’s manual
  • Measure the oil accurately — never estimate the ratio
  • Follow the exact fuel-to-oil ratio specified for the engine model
  • Mix thoroughly before filling the tank

An Accu-Mix 2-Stroke Oil-to-Gas Measuring Bottle makes it easy to measure premix ratios accurately.

Related Products

Parts Desk Insights

This is the right oil for the vast majority of conventional Mercury and Mariner 2-stroke outboards — carbureted, oil-injected, and premix. The 1-litre bottle is a convenient size for topping up an oil reservoir between services or running a premix tank on a smaller engine. The one thing to double-check before buying: if your engine is an OptiMax, a high-output V6, or any engine that runs direct injection, check the owner’s manual first — those engines typically call for Mercury’s dedicated DFI or Premium Plus formula rather than standard TC-W3. Using the wrong oil in a direct-injection engine can lead to deposit buildup and premature wear over time.

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.

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