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Celebrating over 50 years of Trusted Marine Service
Over 50 years of Trusted Marine Service

CRC Knock'er Loose™ Penetrating Solvent

Original price $36.79 - Original price $36.79
Original price
$36.79
$36.79 - $36.79
Current price $36.79
Item locally warehoused

Free returns on all eligible orders

You have 30 days to request a return. All sale items are final sale.

Free seized, rusted, and frozen fasteners fast with CRC Knock’er Loose™ — an industrial-strength, low-viscosity penetrating solvent engineered to cut through the toughest corrosion and get hardware moving again. Its ultra-thin formula wicks rapidly into tight threads, corroded joints, and packed rust layers, dissolving the bond that’s keeping fasteners stuck.

Unlike thicker penetrating oils that sit on the surface, Knock’er Loose™ is formulated to flow into micro-gaps immediately on contact, reaching the corrosion at the source. It also leaves behind a light lubricating film that helps prevent re-seizure after the fastener is freed.

  • Industrial-strength, low-viscosity formula penetrates rust, scale, gum, grease, and corrosion fast
  • Quickly loosens seized, bound, and frozen bolts, nuts, and fittings
  • Leaves a protective lubricating film to prevent future rust and re-seizure
  • Effective on ferrous and non-ferrous metals, including stainless and aluminum
  • Independently tested and verified to outperform competing penetrants

Parts Desk Insights

Best Use Case: Knock’er Loose™ is the right call when you’re dealing with fasteners that have been locked in place by years of saltwater exposure, heat cycling, or galvanic corrosion. It’s particularly effective on prop shaft hardware, outboard motor mounting bolts, trailer coupler pins, and corroded stainless fittings on standing rigging. Apply liberally, allow 10–15 minutes of dwell time for heavy corrosion, and reapply if needed before applying torque. For deeply seized fasteners, a second application after initial movement often frees the thread fully without damage. Keep a can accessible during any haul-out or end-of-season service.

Part Number: 77-73020

Shipping information

In-stock and OEM parts: ship same or next business day.

Locally warehoused items: ship within 3–4 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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Easy Exchanges

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