1. Introduction and Overview
This manual provides comprehensive instructions for the proper installation, operation, and maintenance of your Lewmar Flat Base Ocean Boat Hatch, Size 30. Designed for marine environments, this hatch features a corrosion-resistant anodized aluminum frame and is CE-certified for various boat installations. Please read these instructions carefully before proceeding with installation or use to ensure optimal performance and longevity of the product.

Figure 1.1: Lewmar Flat Base Ocean Boat Hatch, Size 30. This image displays the hatch in a partially open position, showcasing its clear acrylic lid and anodized aluminum frame.
2. Key Features
The Lewmar Flat Base Ocean Boat Hatch Size 30 incorporates several design elements for durability and user convenience:
- CE Certified: Manufactured from high-quality materials, this flat boat hatch is CE certified for deck, coach roof, cockpit, and transom installations, ensuring compliance with European safety standards.
- Corrosion-Resistant: The frame is constructed from anodized aluminum, providing maximum resistance to corrosion in harsh marine environments.
- Easy Mounting: Featuring a flat base, this deck hatch is designed for straightforward installation on various flat surfaces.
- Convenient Opening: Integrated friction levers allow the lid to be held open in any position up to 95 degrees.
- Lockable Handles: Internal and external lockable handles are included for enhanced security.

Figure 2.1: Overview of Key Features. This graphic highlights the lockable handles, corrosion-resistant frame, 95-degree opening capability, and flat base for easy mounting.

Figure 2.2: CE Certification. This image shows a boat hatch installed on a deck, illustrating its suitability for various marine installations as a CE-certified product.

Figure 2.3: Corrosion Resistance. A close-up view of the hatch frame, emphasizing the anodized aluminum construction designed for maximum corrosion resistance in marine environments.

Figure 2.4: Lockable Handles. This image shows the internal handle mechanism, demonstrating the lockable feature for added security.
3. Setup and Installation
The Lewmar Flat Base Ocean Boat Hatch is designed for straightforward installation. Mounting hardware is not included and must be sourced separately, appropriate for your specific boat material and structure.
3.1. Preparing the Mounting Surface
Ensure the mounting surface is flat, clean, and free from obstructions. Mark the precise location for the hatch cutout according to the dimensions provided. It is crucial to verify these measurements before cutting.

Figure 3.1: Approximate Dimensions. This diagram provides the flat cut-out dimensions for the hatch: 12-11/16" L x 17-13/16" W, with overall dimensions of 15.375" x 20.375".
3.2. Cutting the Opening
Carefully cut the opening in your boat's deck or cabin top using appropriate tools. Ensure the edges are smooth and sealed to prevent water ingress and structural damage.
3.3. Securing the Hatch
Position the hatch into the prepared opening. Apply a marine-grade sealant around the flange to create a watertight seal. Secure the hatch using appropriate fasteners (not supplied) through the pre-drilled holes in the frame. Tighten fasteners evenly to avoid distorting the frame.

Figure 3.2: Easy Mounting. This image shows multiple hatches installed on a boat deck, illustrating the flat base design that allows for straightforward surface mounting.
4. Operation
Operating the Lewmar Flat Base Ocean Boat Hatch is simple and intuitive.
4.1. Opening and Closing
To open the hatch, disengage the internal or external lock (if engaged) and lift the lid. The friction levers will hold the lid in any desired open position up to 95 degrees. To close, gently push the lid down until it seats firmly against the frame.
4.2. Using the Friction Levers
The friction levers are designed to maintain the hatch in an open position without additional support. No adjustment is typically required for these levers under normal operating conditions.
4.3. Locking the Hatch
For security, engage the internal or external lockable handles. Ensure the hatch is fully closed before locking to prevent damage.

Figure 4.1: Hatch in Use. This image shows a Lewmar hatch installed on a boat's cabin roof, open to allow ventilation and light.
5. Maintenance
Regular maintenance will extend the life and ensure the proper function of your Lewmar hatch.
- Cleaning: Clean the acrylic lid and aluminum frame regularly with fresh water and a mild, non-abrasive cleaner. Avoid harsh chemicals or abrasive cloths that can scratch the acrylic or damage the anodized finish.
- Seal Inspection: Periodically inspect the rubber seals around the hatch lid for signs of wear, cracking, or compression set. Damaged seals should be replaced promptly to maintain watertight integrity.
- Hinge and Lever Check: Ensure hinges and friction levers operate smoothly. Apply a small amount of marine-grade lubricant to moving parts if necessary.
- Fastener Check: Periodically check all mounting fasteners for tightness. Do not overtighten.
6. Troubleshooting
This section addresses common issues you might encounter with your Lewmar hatch.
6.1. Leaks
If the hatch is leaking, check the following:
- Seal Condition: Inspect the rubber seal for damage or debris. Clean the seal and the mating surface on the frame. If the seal is damaged, it may need replacement.
- Mounting Sealant: The sealant around the frame's flange might have deteriorated or been improperly applied. Re-apply marine-grade sealant if necessary.
- Fastener Tightness: Ensure all mounting fasteners are securely tightened.
- Lens Adhesion: In rare cases, the adhesive holding the acrylic lens to the frame may fail. If this occurs, contact Lewmar customer support for guidance.
6.2. Stiff Operation
If the hatch is difficult to open or close, check for:
- Debris: Clear any debris from the hinges or around the seal.
- Lubrication: Apply a marine-grade lubricant to the hinge points and friction lever mechanisms.
7. Specifications
| Attribute | Detail |
|---|---|
| Brand | Lewmar |
| Model | Lewmar Flat Base Ocean Hatch For Boats - Size 30 |
| Item Model Number | 39630050 |
| Item Weight | 2.2 pounds (approximately 1 kg) |
| Package Dimensions | 22.2 x 17.2 x 3.1 inches (approximately 56.4 x 43.7 x 7.9 cm) |
| Manufacturer Part Number | 39630050 |
| Certifications | CE Certified |
| Material | Anodized Aluminum Frame, Acrylic Lid |
| Opening Angle | Up to 95 degrees |
| Included Components | Hatch (mounting hardware not included) |
8. Warranty and Support
For warranty information and customer support, please contact Lewmar directly. Details regarding warranty periods and claims procedures can typically be found on the official Lewmar website or by contacting their customer service department. It is recommended to retain your proof of purchase for any warranty claims.
You can visit the official Lewmar store for more information: Lewmar Store





