Sea-Dog 3214621 Gas Filled Lift Spring
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Sea-Dog 3214621 — Gas Filled Lift Spring
| Part Number | 3214621 |
|---|---|
| SKU | 354-3214621 |
| Brand | Sea-Dog Line |
| Product Type | Gas Filled Lift Spring (Gas Strut) |
| System | Marine Hatch, Lid & Access Panel Support |
| Body Material | Heavy gauge steel |
| Shaft Finish | Hard chromium plated steel |
| Bushings | Bronze |
| End Fittings | Polymer |
| Seal Type | Multi-lobe (unique Sea-Dog design) |
| Weight | approx. 138 g |
Note: Extended length, compressed length, and force rating (lbs) should be confirmed from the Sea-Dog product datasheet or packaging before installation. Verify these dimensions match your hatch or lid application before ordering.
Overview
The Sea-Dog 3214621 is a gas filled lift spring designed to provide controlled, hands-free support for marine hatches, engine compartment lids, seat lids, and other hinged access panels on boats. The nitrogen-charged cylinder provides smooth, consistent lift force to hold lids open securely at any position, eliminating the need for prop rods. The unique multi-lobe seal design helps maintain gas pressure and extend service life in the demanding marine environment.
Key Features
- Gas-filled (nitrogen) cylinder provides smooth, consistent lift force
- Unique multi-lobe seal design for improved pressure retention and seal longevity
- Heavy gauge steel body for durability in marine environments
- Hard chromium plated shaft resists corrosion and wear
- Bronze bushings for smooth, low-friction operation
- Polymer end fittings — corrosion-resistant mounting points
- Holds hatches and lids open hands-free without prop rods
Compatible Applications
- Marine engine compartment hatch lids
- Boat storage hatch and seat lid support
- Bow locker and stern locker access panels
- Any hinged marine hatch or lid requiring gas spring support
- Replacement for worn or failed OEM gas springs on compatible hatches
Installation Notes
- Verify extended length, compressed length, and force rating match your existing hatch or lid geometry before ordering — incorrect sizing will result in the lid not holding open or over-extending
- Mount with the cylinder end up and piston rod end down where possible for optimal seal performance and longest service life
- Use appropriate stainless or corrosion-resistant fasteners through the polymer end fittings
- Do not drill, weld, heat, or attempt to disassemble the gas cylinder — it is pressurized
- Ensure the spring operates through its full range of motion without binding before finalizing mount positions
Technical Notes / FAQ
- How do I know what force rating I need? A common starting point is to use two gas springs, each rated at approximately 60% of the lid’s weight, mounted at equal distances from the hinge. For heavy lids, consult the hatch manufacturer’s specification or a gas spring sizing guide.
- Can I use one spring instead of two? A single spring can work on narrower or lighter hatches, but two springs balanced symmetrically across the hinge width provide more stable, even lift.
- My old spring no longer holds the lid open — can it be recharged? No — gas springs cannot be refilled or recharged. Replace with a new unit matching the original specifications.
- What orientation is correct? Piston rod down is recommended for most applications — this keeps lubricant inside the cylinder around the piston seal and extends life.
Parts Desk Insights
Best Use Case: This spring is a go-to replacement for engine hatch and storage lid support on runabouts, center consoles, and pontoons where the original gas spring has lost pressure or failed. Customers replacing a weak or collapsed spring should bring the old unit’s measurements (extended length, compressed length, end fitting style) to confirm the correct replacement before ordering.
Common Issues: The most frequent problem is customers ordering without checking the extended and compressed lengths, then finding the spring won’t fit their hatch geometry. Always encourage customers to measure the existing spring or the mount-point-to-mount-point distance at full open and full closed before selecting a replacement. The second common issue is the lid slowly drifting down after installation — usually caused by a force rating that’s too low for the lid weight; upsizing to a higher-force spring or adding a second spring resolves it.
Related Products
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.