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Trusted Marine Parts & Lower Units Supplier Since 2001

Serving boat owners since 2001, Mariners Warehouse offers genuine marine parts, OEM & aftermarket lower units, and essential boating equipment with fast nationwide shipping, expert support, and service you can trust.
Trusted by Thousands of Boaters
25 YEARS
Serving Boaters Since 2001
best-quality
Genuine OEM & Premium Aftermarket Parts

Why Choose Mariners Warehouse?

At Mariners Warehouse, we don't just sell marine gear — we live the maritime lifestyle. From passionate boaters to weekend adventurers, we understand what you need because we use it ourselves.

We carefully handpick every product for quality, performance, and durability, so you can spend less time worrying and more time on the water.

Premium Quality

Top-grade marine gear built to last.

Best Value

Competitive prices without compromise.

Trusted & Reliable

Thousands of happy boaters trust us.

Expert Support

Real people who know boating.

Mariners Warehouse products on a boat deck

What our customers get

Generic marine store shelves

Typical marine store

Features Mariners Warehouse Other Marine Stores
Product Quality
Premium, marine-grade, built to last
Often standard or low-grade quality
Pricing
Best value with fair, transparent pricing
Higher prices for similar quality
Product Range
Curated, reliable & useful products
Overstocked with unnecessary items
Customer Support
Real experts who understand boating
Limited or generic support
Return & Warranty
Hassle-free returns & brand warranties
Complicated return policies
For Boaters, By Boaters
We use what we sell – trusted by the boating community
Just another retail store

What Customers Say

Mapping Has Been Reliable So Far

Been running a Humminbird unit for a few months now mainly for the mapping and structure detection, and it's held up well across different lakes I've fished. Setup took some patience the first time but customer support was helpful when I had a question about updating the maps.


Screen Clarity Is Better Than My Old Unit

Upgraded to a Humminbird fish finder this season and the screen is noticeably sharper than what I was using before, even in direct sunlight. Menu navigation took a bit to get used to but once I found my usual settings it's been easy to use on the water.


Solid Experience From Order to Install

Bought a trolling motor bracket and a couple of accessories together, everything arrived in one shipment and matched what I ordered. Install went smoothly since the fitment details on the site were accurate, no surprises when I got to the boat.


Good Aftermarket Option, Worth the Prep Work

Went with an aftermarket lower unit instead of paying OEM prices and it's held up well over the season so far. Took a little extra time gathering my shaft length and current gearcase info before ordering, but that upfront work meant no fitment issues once it arrived.


Detailed Listings Made Comparison Easy

Was trying to decide between a couple of Nautica scooter models for a trip and the product descriptions actually explained the tradeoffs instead of just listing specs. Made the decision a lot easier than trying to piece it together from other sites.


Straightforward Return When I Ordered the Wrong Part

Ended up ordering the wrong shaft length for a lower unit, my mistake not the listing's fault, and the return process was easier than I expected. No back and forth hassle, just processed it and I reordered the correct one a few days later.


Right Part After Confirming My Engine Details

Needed a replacement lower unit for my outboard and made sure to have the full engine model and PID ready before ordering since the listing was clear that horsepower alone wasn't enough. Glad I did, the fit was exact and installation went without any surprises. Customer name: Desmond Ravensworth


Reliable for Repeat Orders

This is my third order from Mariners Warehouse now, mostly Minn Kota accessories and a couple of engine parts. Every order has arrived correctly packaged and on time, which is honestly why I keep coming back instead of shopping around.


Customer Service Actually Helped

Had a question about compatibility for a Suzuki lower unit before ordering and got a real answer instead of a generic response. That kind of thing matters when you're spending real money on a part you can't easily return once installed.


Solid Install, Just Confirm Thrust First

Installed a Minn Kota trolling motor on my boat over the weekend and the transom mount was straightforward. My only advice is to actually confirm the thrust rating matches your boat weight before ordering, I almost went with a lower thrust than I needed based on the listing but a quick call sorted that out.


Good Selection Across Different Brands

Was comparing sea scooters and outboard parts for two different projects and appreciated that everything I needed was on one site instead of hopping between five different stores. Product pages had enough detail to actually compare options instead of guessing.


Fast Shipping, No Surprises

Ordered a Minn Kota battery charger and it showed up quicker than the estimate on the site. Packaging was solid too, nothing rattling around inside. Been buying boat parts online for years and this was one of the smoother experiences I've had.


Positioning Feature Is a Game Changer for Solo Trips

Picked up a Minn Kota trolling motor with GPS positioning after years of manually holding a spot, and fishing alone is so much easier now. Learning the remote took a weekend but now it's second nature. Quiet enough that it doesn't spook fish either, which was a bigger concern than I expected.


Knew Exactly What I Needed

Called in before ordering a replacement lower unit for my Yamaha since I wasn't sure which variant matched my engine, and the team walked me through confirming the PID and shaft length before I placed the order. Got the right part the first time, which hasn't always been my experience buying marine parts online.


Been a Dependable Source for Boat Parts

Started ordering from here for a specific lower unit I couldn't find elsewhere and have kept coming back since for other gear. Prices are reasonable and the site makes it easy to find the exact variant I need instead of guessing off horsepower alone.


Helpful Before I Even Placed the Order

Emailed with a question about a part before buying and got a response within a day with a clear answer, not just a copy-paste reply. That gave me enough confidence to go ahead with the order, and everything showed up as described.


Helping boaters find the right parts with confidence.

Anchored in Expertise: The Mariners Warehouse Story

At Mariners Warehouse, we believe finding the right marine part should be simple and reliable. Built by a team passionate about the boating industry, our mission is to connect boat owners, mechanics, and marine professionals with high-quality marine parts, trusted fitment expertise, and dependable service. Every order is backed by a commitment to helping you stay on the water with confidence.

✔ Extensive Inventory of marine parts and equipment

✔ Expert Guidance for accurate fitment and compatibility

✔ Fast Fulfillment to minimize downtime

Need Help?

Still Can't Find the Right Marine Part?

Finding the right replacement part shouldn't be frustrating. If you can't locate the marine part you need, our experienced support team is here to help. Whether you have a part number, engine model, or simply need expert guidance, we'll help you find the correct replacement so you can get back on the water with confidence.

Trusted by 50,000+ boat owners across the USA

A man wearing a navy blue polo shirt with a circular logo sits at a desk holding a metal engine component, with a laptop in front of him and a boat propeller on the table. A dark blue informational overlay on the right lists benefits like 'Talk to an Expert' and 'Find the Right Part'.
  • Expert Marine Support

    Our team has years of experience in marine parts.

  • Fast Response

    We respond quickly to get you the help you need.

  • Find Compatible Parts

    We make sure you get the right part the first time.

  • Huge Selection

    Access to 50,000+ marine parts & accessories.

Have a Part Number or Engine Model?

Send it to us and our experts will help you find the exact part you need.

FAQ's

Find answers to common questions below

Mariners Warehouse offers more than 50,000 marine product listings, including outboard lower units and gearcases, MerCruiser sterndrives and outdrives, propellers, trolling motors, shallow water anchors, marine electronics and navigation equipment, electrical components, anchoring and docking gear, maintenance supplies, seascooters, coolers, and more.

Browse our complete marine parts and boat accessories directory to shop by category. Product availability, condition, and included components vary by product and are shown on the individual listing.

Do not select a fitment-critical marine part by horsepower, model year, or product appearance alone. Before ordering, match the following information:

  • Boat or engine manufacturer
  • Complete model and serial number
  • Current OEM or manufacturer part number
  • Engine type and configuration
  • Gear ratio and shaft length, where applicable
  • Standard or counter rotation, where applicable

Review the compatibility information on the product page. If any detail is unclear, contact our marine parts team before placing your order.

For faster and more accurate fitment assistance, please provide:

  • Boat or engine make
  • Complete model number
  • Complete serial number
  • Model year and horsepower
  • Current OEM or manufacturer part number
  • A clear photo of the identification plate or existing part

For lower units and sterndrives, also include the gear ratio, shaft length, rotation, and engine configuration. Complete information helps reduce wrong-part orders, returns, and installation delays.

Yes. Send us the existing OEM or manufacturer part number, product brand, engine or boat details, and clear photos of the old part or identification label.

Our team can review the available catalog information, help identify a possible replacement, or explain what additional information is needed.

Visit our Contact Us page, call +1 888 812 6287, or email info@marinerswarehouse.com .

OEM marine parts are sold under the original equipment manufacturer’s brand. New aftermarket parts are newly manufactured replacements produced by another manufacturer for specified marine applications. Remanufactured parts are rebuilt from serviceable used cores using inspected, reconditioned, or replacement components.

The best option depends on exact fitment, product condition, price, included components, core-return requirements, availability, and warranty—not price alone. Always review the selected product and variant before ordering.

No. Warranty coverage depends on the manufacturer, exact SKU, product condition, and application.

For example, eligible SEI assembled lower units may include a three-year fault-free manufacturer warranty, while OBR and other new or remanufactured products can have different warranty periods, requirements, and exclusions.

Review the warranty information on the selected product page and the manufacturer’s written warranty terms. If the coverage is unclear, contact our team for confirmation before checkout.

Orders are generally processed within 1–2 business days, Monday through Friday. After processing, estimated shipping times are:

  • Standard shipping: 3–7 business days
  • Expedited shipping: 2–3 business days
  • Overnight shipping: 1 business day

Processing and transit times are separate. Delivery estimates may vary based on destination, product availability, carrier conditions, weather, and shipping volume. See our complete Shipping Policy for additional information.

Shipping charges are calculated using the product’s weight and dimensions, delivery destination, and selected shipping method. The available shipping cost will be displayed at checkout before you complete your order.

Once your order ships, you will receive a shipping-confirmation email containing the carrier’s tracking number so you can monitor the delivery.

International shipping is available to selected countries. Delivery time depends on the destination, selected shipping service, customs processing, and carrier availability.

Import duties, taxes, brokerage fees, and other destination charges may apply and are generally the customer’s responsibility. Review the available shipping options at checkout or contact us before ordering if you need assistance with an international shipment.

Eligible products may be returned within 14 days from the shipment date after obtaining a Return Authorization Number.

  • Items must remain in their original condition.
  • Opened items must include all original components.
  • Assembled, installed, used, or rented products cannot be returned.
  • Returns are currently subject to a 10% restocking fee.
  • Original shipping charges are non-refundable.

Please read our complete Refund Policy and contact us before returning any product. If a part appears incorrect, do not install it—contact our team first.