Lewmar bow thrusters are a valuable asset for boat owners, providing maneuverability in tight spaces and challenging conditions. However, like any underwater component, they require regular maintenance, and one crucial aspect is replacing the zinc anode. This guide provides a comprehensive overview of how to change your Lewmar bow thruster zinc underwater, ensuring the longevity of your thruster and preventing costly corrosion.
Why Change Your Lewmar Bow Thruster Zinc?
Your Lewmar bow thruster zinc is a sacrificial anode, designed to corrode instead of the more expensive thruster components. Saltwater is highly corrosive, and the zinc's role is to attract and absorb this corrosion, protecting the thruster's metal parts. Once the zinc is significantly depleted, it's no longer effective, leaving your thruster vulnerable to damage. Regular inspection and replacement are crucial for preventing expensive repairs or even thruster failure.
How Often Should I Change My Lewmar Bow Thruster Zinc?
The frequency of zinc replacement depends on several factors, including the salinity of the water, the amount of time your boat spends in the water, and the overall condition of the zinc itself. As a general guideline, inspect your zinc at least every six months and replace it as needed. A severely corroded zinc (showing significant pitting or less than half its original size) should be replaced immediately.
What Tools Do I Need to Change My Lewmar Bow Thruster Zinc?
Before starting the process, gather the necessary tools:
- New Lewmar Bow Thruster Zinc: Ensure you purchase the correct replacement zinc specifically designed for your Lewmar thruster model.
- Wrench: A suitable wrench for removing the old zinc. The size will vary depending on your thruster model. Consult your owner's manual.
- Gloves: Protect your hands from saltwater and potential sharp edges.
- Scuba Gear (Optional but Recommended): While it might be possible to change the zinc from the dock, using scuba gear provides superior visibility and accessibility, especially if your thruster is mounted lower on the hull.
- Wire Brush (Optional): This can help clean the mounting surface before installing the new zinc.
- Anti-Fouling Paint (Optional): Applying a thin layer of anti-fouling paint to the zinc before installation can help prevent marine growth.
How to Change Your Lewmar Bow Thruster Zinc Underwater: A Step-by-Step Guide
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Inspection: Before starting any work, thoroughly inspect the existing zinc for wear and tear. If it's significantly corroded, proceed with the replacement.
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Access: Access the zinc anode. This may involve removing a access panel or diving to inspect the thruster.
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Removal: Use the appropriate wrench to carefully remove the old zinc anode. Note the orientation of the zinc before removal for correct reinstallation.
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Cleaning: Clean the mounting surface of the thruster using a wire brush to remove any corrosion or marine growth.
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Installation: Carefully install the new Lewmar bow thruster zinc, ensuring it's correctly seated and aligned. Tighten the nut securely.
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Post-Installation Check: After installation, ensure the new zinc is securely attached and there are no leaks.
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Dive inspection (if applicable): Inspect the thruster and zinc again after a short period to make sure that the zinc is not leaking and making contact.
What Happens if I Don't Replace My Lewmar Bow Thruster Zinc?
Neglecting to replace a depleted zinc anode puts your Lewmar bow thruster at serious risk. Corrosion will attack the thruster's more expensive components, potentially leading to:
- Reduced Thruster Performance: Corrosion can restrict moving parts, affecting the thruster's power and efficiency.
- Major Repairs: Extensive corrosion can require costly repairs or even complete thruster replacement.
- Unexpected Failure: A severely corroded thruster might fail completely at the worst possible time.
Can I Replace My Lewmar Bow Thruster Zinc Myself?
While you can attempt to replace the zinc yourself, it's important to assess your comfort level with underwater work and your mechanical aptitude. If you're unsure about any aspect of the process, it's always best to consult a qualified marine mechanic.
What is the best type of zinc to use for my Lewmar Bow Thruster?
Lewmar recommends using their own brand of zincs specifically designed for their thrusters. Using an incompatible zinc could lead to issues and potential damage. Check your thruster's manual for the correct type of zinc anode to use.
By following these steps and regularly inspecting your Lewmar bow thruster zinc, you'll ensure the continued performance and longevity of this important piece of equipment. Remember, prevention is far cheaper than costly repairs.
