Our premium replacement for MerCruiser® sterndrives applications ensures perfect compatibility, durability, and enhanced performance for a smooth boating experience. Designed specifically for MerCruiser® sterndrives, this part guarantees reliable operation and long-lasting quality.

#1

Welcome to BoatPartsBay.com, the online destination for all your boat part needs. We specialize in sterndrive parts, inboard/outboard engine parts, and a huge range of general marine accessories. Whether you’re a seasoned marine mechanic, a boat owner doing DIY repairs, or a fisher gearing up for the next trip, our extensive catalog and expert service have you covered. We combine technical expertise with a friendly, helpful approach so you get the right parts with a great experience – every time.

At BoatPartsBay, you’ll find OEM-quality parts from top industry brands and suppliers. We carry components compatible with Mercury®/MerCruiser®, Volvo Penta®, OMC® (Johnson/Evinrude), Yamaha®, Suzuki®, and more​

. Through our partnership with Sterndrive Engineering (SEI) and major distributors like Donovan Marine, we give you access to thousands of products – from critical engine spares to boating accessories – all in one place. Every item is brand-new (not rebuilt) and sourced from trusted manufacturers, ensuring reliability on the water. Plus, many of our products come backed by robust warranties for your peace of mind (including an industry-leading 3-year fault-free warranty on SEI sterndrive units and outboard lower units​

).

Sterndrive Parts – Durable Outdrives & Lower Units with 3-Year Warranty

Our Sterndrive Parts selection is second to none. We stock complete replacement sterndrives, lower units, and sterndrive components for all major inboard/outboard systems. This includes MerCruiser® Alpha One (Gen I & Gen II), the Bravo series, Volvo Penta® SX, OMC Cobra®, and others – all precision-engineered to meet or exceed OEM specifications​

. These sterndrive units are 100% new, not remanufactured, so you get the full lifespan and performance you expect. In fact, we are proud to offer Sterndrive Engineering (SEI) aftermarket drives that directly replace MerCruiser and other popular sterndrives​

at a fraction of the cost of OEM parts.

Key features of our sterndrive units:

• Fault-Free 3-Year Warranty: All SEI complete sterndrives and lower gearcases come with a 3-year fault-free warranty​
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  – the best in the industry. This warranty covers any failure requiring repair or replacement, even those caused by accidents or neglect (for example, damage from lack of oil, fishing line tangles, or impact)​

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  . Enjoy true peace of mind knowing your investment is protected far beyond the standard one-year term offered on many OEM parts.

• OEM-Compatible Design: Our sterndrive replacements are engineered as direct-fit solutions for your boat. They match the gear ratios, spline counts, and mounting patterns of the original MerCruiser, Volvo, or OMC units, ensuring easy installation and seamless integration with your engine. No modifications needed – just bolt on and go.
• High-Quality Construction: Built with marine-grade alloys and precision-forged gears, these drives are made to withstand harsh marine environments. They deliver smooth, quiet operation and long-term durability comparable to (or better than) OEM performance​
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  ​

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  . You’ll be back to enjoying the water with confidence in your propulsion system.

• Complete Assemblies & Components: Whether you need a complete upper and lower unit assembly for a MerCruiser Alpha One, or just a specific sterndrive part like a gimbal bearing, U-joint, exhaust bellow, or trim/tilt cylinder, we have it all. Our catalog covers every component to rebuild or service your sterndrive. Browse our Sterndrive Parts section to find drives and parts for Alpha One, Bravo, Cobra, Volvo SX, and more, each detailed with compatibility information.

Example Sterndrive Products and Specifications:

Every sterndrive and lower unit we sell is backed not only by warranty but also by our technical support. Unsure which sterndrive is right for your engine? Check out our Sterndrive Buyer’s Guide or contact our team for expert guidance. We’ll help you identify the correct model (e.g. Alpha I vs. Gen II, gear ratio, standard or counter rotation) to match your boat. With BoatPartsBay, replacing your sterndrive is hassle-free – from selection to installation.

Inboard & Outboard Engine Parts – Keep Your Motor Running Strong

BoatPartsBay offers a comprehensive array of engine parts for both inboard and outboard motors. Maintaining your boat’s engine is crucial for safety and performance, and we make it easy to find exactly what you need. Our inventory covers gasoline and diesel inboard engines, as well as all major outboard brands and models, so you can source parts for everything from a small 2-stroke outboard up to big-block V8 inboards.

What engine parts are you looking for? We likely have them in stock and ready to ship:

• Fuel System Components: Carburetors and rebuild kits, fuel pumps, injectors, filters, fuel tanks and lines. Keep your engine fueled cleanly and efficiently.
• Electrical & Ignition: Spark plugs, plug wires, ignition coils, distributor components, stators and triggers, alternators, starters, and solenoids. We even carry hard-to-find CDI electronic modules and regulators for outboards. (Select electrical parts come with a 1-Year Warranty for reliability​
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  .)

• Cooling System: Water pumps (impellers and pump kits for outboards, raw water pumps for inboards), thermostats, heat exchangers, hoses and clamps. Prevent overheating by servicing these critical cooling parts.
• Engine Internals & Maintenance: Pistons, rings, gasket sets, seals, oil filters, drive belts, and more for common marine engines (MerCruiser, Volvo Penta, Crusader, PCM, Yamaha outboards, etc.). Whether you’re doing a minor tune-up or a major overhaul, we have the internal engine parts and kits you need.
• Exhaust & Intake: Manifolds, risers, elbows, mufflers, intake filters/flame arrestors – all the parts to ensure your engine breathes properly and expels exhaust safely. (We stock popular MerCruiser and Volvo manifold/riser kits with gaskets and bolts included.)
• Propulsion & Drive Parts: Propellers (aluminum & stainless steel props in various sizes and pitches), prop shafts, hubs, trim motors, and control cables. These might be considered accessories by some, but we know they’re integral to engine performance and we’ve got them in our Engine Parts catalog.

Our engine parts selection is sourced from reputable manufacturers like Sierra Marine, Mallory, Mercury Quicksilver, Volvo Penta OEM, and top aftermarket suppliers. That means you can count on quality and fit – parts that meet the original specs of your engine. Many items are direct OEM replacements, so installation is straightforward. We provide detailed product descriptions, specifications, and OEM part number cross-references to help you verify compatibility. If you have the OEM part number from Mercury, Yamaha, etc., you can search our site to find the matching replacement quickly.

1-Year Warranty on Electrical Parts: We stand behind the quality of our engine parts. Most electrical components (starters, alternators, power trim motors, etc.) include a 1-year manufacturer’s warranty for defects​

. This gives you confidence that if anything isn’t up to par, we’ll make it right. (And as mentioned, sterndrive and lower unit assemblies carry an unmatched 3-year warranty for fault-free service.)

Expert Tip: Unsure about what part you need? Check our Engine Diagrams or FAQ section below for guidance on identifying your engine model and serial number. We also have a knowledgeable customer support team ready to assist – we can help cross-reference old part numbers or recommend maintenance kits for your specific motor. Keeping your engine running strong is our top priority, and we’re here to help every step of the way.

Marine Accessories & Supplies – Everything for Your Boat in One Bay

Beyond engines and drives, BoatPartsBay is a full-service marine supply store. Our Marine Accessories catalog covers all the extra equipment and boat accessories that make your time on the water safe, enjoyable, and hassle-free. From routine maintenance items to safety gear and creature comforts, think of us as your boating hardware store online.

Our marine accessory categories include:

• Boat Maintenance Supplies: Oils and lubricants (engine oil, gear lube, 2-stroke oil), fuel additives, cleaning supplies, paint and gelcoat repair kits. We have the essentials to keep your boat well-maintained.
• Electrical & Lighting: Marine batteries, onboard battery chargers, switch panels, wiring and connectors, fuses, LED navigation lights, interior lighting, horns, and marine audio systems. Upgrade your boat’s electrical systems with confidence.
• Safety Equipment: Life jackets (PFDs) for adults and kids, throwable life rings, flares, first aid kits, fire extinguishers, EPIRBs/PLBs, and survival gear. Safety is paramount, and we stock U.S. Coast Guard-approved equipment to outfit your vessel.
• Anchoring & Docking: Anchors (fluke, plow, etc.), anchor rode and chain, windlasses, dock lines, fenders, cleats, winches, and dock hardware. Secure your boat at the dock or on the shoreline with quality anchoring gear.
• Pumps & Plumbing: Bilge pumps (automatic and manual), livewell pumps, washdown systems, marine toilets (head) and sanitation supplies, hoses and fittings. Keep your boat dry and systems flowing properly.
• Navigation & Hardware: Compasses, GPS/fishfinders, marine radar, and VHF radios for navigation and communication. We also carry helm controls, steering systems, cables, gauges, and other hardware. If it’s part of your boat’s operating system, we likely have it.
• Fishing & Recreation Accessories: Rod holders, tackle storage, downriggers, coolers, baitwell equipment, and more for the fishing enthusiasts. Plus, boat covers, bimini tops, seats, and other comfort accessories to enhance your boating experience.

In partnership with Donovan Marine’s extensive distribution network, we’re able to offer “everything but the boat.” This includes niche and specialty items often hard to find elsewhere. From anchors and horns to life rafts and deck fittings​

, if it’s in Donovan’s 2025 marine catalog, you can bet we can get it for you. We stock trusted marine brands like Perko (navigation lights and deck hardware), Rule (bilge pumps), Attwood, SeaStar (Teleflex steering and controls), Blue Sea Systems (electrical components), and many more. All accessories are marine-grade, built to withstand salt, sun, and harsh conditions.

Shopping for accessories on BoatPartsBay is easy: browse by category or search for specific items. Each product page provides specifications and usage info, so you know you’re getting the right item (e.g. the correct size bilge pump or the right anchor type for your boat size). Because we utilize a dropshipping model with our suppliers, virtually any marine product you need is just an order away – even if it’s not listed on our site yet, contact us and we can likely source it quickly.

Why Choose BoatPartsBay?

Choosing BoatPartsBay means choosing quality, convenience, and value. We aim to be more than just a store – we’re your boating partner. Here are a few reasons boat owners and professionals across North and South America trust us:

• Extensive Inventory & Brands: By integrating catalogs from SEI and Donovan Marine, we offer one of the largest selections of boat parts online. You get the convenience of finding all major sterndrive models, engine parts, and accessories in one place, instead of searching multiple stores. Mercury, Yamaha, MerCruiser, Volvo, OMC, Sierra, Perko… the list goes on​
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  – we have them all.

• Competitive Pricing: Our direct dealer relationships and dropship model let us keep prices low. You’ll find aftermarket alternatives (like SEI sterndrives) that save you 30-50% compared to OEM parts, without sacrificing quality. We regularly benchmark against top competitors to ensure our content and prices offer more value for your money.
• Expertise & Support: We’re not just order-takers; we’re boating enthusiasts and technicians. Need help identifying a part or troubleshooting an issue? Our team’s technical knowledge sets us apart. We provide resources like guides and FAQs, and you can reach out for personalized support. We’ll help make sure you get the right part the first time.
• Fast, Reliable Shipping: We know you need your parts ASAP to get back on the water. That’s why we work with multiple warehouses across the USA to ship your order quickly. Most in-stock orders are processed within 1 business day, with options for expedited shipping. We also accommodate international shipping, so no matter where you boat, we’ll deliver to you.
• Secure & Hassle-Free Shopping: Our website is secure and easy to use, with detailed product listings and customer reviews coming soon. We offer multiple payment options and an “Order Now” checkout that keeps things simple. Because we say “Order Now” (not “Buy Now”), you can be assured that we double-check stock and fulfillment with our suppliers for a smooth dropship experience. If any issues arise, our customer service will keep you informed and make it right.

In short, BoatPartsBay is committed to quality, affordability, and customer satisfaction. Our goal is to get you the right parts when you need them, so you can spend more time boating and less time waiting.

Frequently Asked Questions (FAQ)

Below we’ve answered some common questions from boaters and mechanics. If you don’t see your question, feel free to reach out – we’re here 24/7 to help with your marine part needs!

Q: Which sterndrive models do you carry replacements for?
A: We carry replacement sterndrives for all popular models. This includes MerCruiser® Alpha One Gen I (pre-1991), Alpha One Gen II (1991 & newer), and Bravo I/II/III drives, as well as Volvo Penta® SX series and OMC Cobra® sterndrives. Our Sterndrive Engineering (SEI) units are designed as drop-in replacements for these models​

. For example, SEI’s SE-106 model covers MerCruiser Alpha Gen I drives (1972-1990) and SE-116 covers Alpha Gen II (1991-present), each with the correct gear ratios available. We also offer outboard lower units for Yamaha, Mercury, Johnson/Evinrude, and more – all of which come with the 3-year no-fault warranty. If you have a specific engine or drive, use our Part Finder or contact us with your engine’s model/year and we’ll point you to the correct sterndrive or lower unit.

Q: Do your parts come with a warranty?
A: Yes! Warranties are a big part of our value. All complete sterndrives and outboard lower units include a 3-Year Fault-Free Warranty​

from SEI. This warranty is unconditional, covering any failure that requires repair or replacement – even damage due to accidents or user error is covered​

. Additionally, many of our other parts carry a 1-Year manufacturer’s warranty, especially electrical components like starters, alternators, power trim motors, etc.​

. We will clearly indicate warranty information on the product pages. Rest assured, we stand behind the products we sell. If a part fails prematurely under normal use, we’ll work with you to get it repaired or replaced fast, so you’re not off the water for long.

Q: Are the parts you sell OEM or aftermarket?
A: We sell a mix of OEM and high-quality aftermarket parts. Our goal is to give you options for your budget and needs. We source OEM parts for those who want the exact same part from the engine manufacturer (for example, genuine Mercury Marine or Yamaha parts). However, we also offer aftermarket alternatives (like SEI, Sierra, Mallory) that meet or exceed OEM specifications, often at a lower price. For instance, SEI sterndrives are aftermarket replacements for MerCruiser drives that cost much less but maintain OEM-level performance and fit. They even come with a longer warranty than many OEM parts (3 years vs. 1 year)​

. On each product page, we’ll indicate if it’s OEM or aftermarket, and list any corresponding OEM part numbers it replaces. Rest assured, every part – OEM or not – is new, marine-grade, and quality-tested for reliability.

Q: How do I find the right part for my engine or boat?
A: We try to make this easy. Here are a few tips:

• Use our Part Finder / Diagrams: We provide online parts catalogs and diagrams (for Mercury/MerCruiser, Johnson/Evinrude, Yamaha, etc.) where you can locate your engine model and see exploded views of all parts. This can help you get the correct part number.
• Search by Part Number: If you already have an OEM part number (from a manual or the old part), enter it in our search bar – often our system will show the exact match or an equivalent replacement.
• Filter by Brand/Model: Browse our site by selecting your engine brand and model series (e.g., MerCruiser 5.7L, or Yamaha 150HP 2-Stroke). We’ve organized products so you can see what fits your specific setup.
• Ask Us: When in doubt, contact our support via phone, email, or chat. We can quickly help verify fitment. Our team may ask for details like your engine’s serial number, year, model, or drive type. With that, we can confirm the exact parts or kits you need. We’re here to ensure you order the right item.

Q: Does BoatPartsBay ship internationally?
A: Yes, we do. We primarily serve the USA and the Americas, but we can ship orders worldwide. During checkout, you’ll see available shipping options based on your address. We partner with reliable couriers (UPS, FedEx, DHL, etc.) to deliver globally. International customers are responsible for any customs or import duties, but we’ll help by providing proper documentation and efficient shipping service. No matter where you are, we’ll strive to get you your parts quickly and at a reasonable shipping cost. And for our U.S. customers, enjoy fast shipping from our domestic warehouses – many customers in the continental US receive their orders in 2-5 business days with our standard shipping.

Q: Why does the site say “Order Now” instead of “Buy Now”?
A: Great observation! We use “Order Now” because of how our fulfillment works. BoatPartsBay operates on a direct ship-to-you model (dropshipping) with our suppliers. This means when you place an order, we might not pull the item from our own shelf, but directly from the manufacturer or distributor’s inventory (for instance, Donovan Marine’s warehouse). By saying “Order Now,” we want to communicate that we’ll process your order and coordinate the shipment for you. It’s essentially the same as “Buy Now,” but it reflects that slight difference in process. The upside of this model is access to a much larger inventory and often fresher stock, since parts come straight from the central source. While delivery times are usually very fast, on rare occasions there might be a short lead time if our supplier needs to bring an item in – but we’ll always keep you informed. In short, “Order Now” is just our way of saying click here to get this item delivered to you!.

#2 BoatPartsBay – Your One-Stop Shop for Sterndrive Parts, Engine Components & Marine Accessories

Welcome to BoatPartsBay.com, your ultimate online store for high-quality sterndrive parts, inboard/outboard engine parts, and a massive selection of marine accessories. Whether you’re a seasoned marine mechanic, a boat owner performing DIY repairs, or a fisher preparing for your next expedition, BoatPartsBay connects you with the parts and accessories you need. Our extensive inventory, technical expertise, and customer-first approach ensure you always get the right part at the best price.

BoatPartsBay provides access to OEM-compatible and aftermarket marine parts built to industry-leading standards. Customers can order boat engine components, propulsion systems, electrical parts, fuel system components, marine safety gear, and much more. Products are sourced from top-tier manufacturers, ensuring quality, performance, and durability on the water. Plus, many items come with an industry-best 3-year fault-free warranty on sterndrive units and outboard lower units, along with a 1-year warranty on select electrical parts.

🔥 Why Choose BoatPartsBay? 🔥

✅ Extensive Selection of Marine Parts

BoatPartsBay connects customers to a wide range of boat engine parts, sterndrives, propellers, electrical systems, and more. Available products are compatible with Mercury®, MerCruiser®, Yamaha®, Volvo Penta®, Suzuki®, Honda®, Evinrude®, and Johnson® engines, ensuring that the right part for the job is always within reach.

✅ Competitive Pricing – Quality Meets Affordability

BoatPartsBay ensures affordable pricing on high-quality marine parts, allowing customers to save 30-50% compared to OEM parts without sacrificing performance. Prices are regularly benchmarked against leading competitors to ensure the best value on the market.

✅ Expert Advice & Customer Support

Need help finding the right part? The marine specialists at BoatPartsBay provide expert support to make the shopping experience hassle-free. Whether it’s sterndrive compatibility assistance, installation guidance, or boat maintenance tips, reliable advice is available at every step.

✅ Fast & Reliable Shipping

Time on the water is precious, which is why BoatPartsBay facilitates fast processing and shipping across the USA, South America, North America, and international markets. Orders are shipped quickly and securely through trusted shipping partners.

🛠️ Sterndrive Parts – Top-Quality Replacements with 3-Year Warranty

The sterndrive parts catalog is extensive. Whether customers need a complete sterndrive unit, an outboard lower unit, or essential sterndrive replacement parts, everything necessary for repairs and replacements is available. Options include direct replacements for:

• MerCruiser® Alpha One (Gen I & Gen II) sterndrives

• MerCruiser® Bravo Series (Bravo One, Bravo Two, Bravo Three)

• Volvo Penta SX, DP-S sterndrives

• OMC Cobra sterndrive units

• Yamaha sterndrive replacements

🏆 Key Features of Available Sterndrive Units:

✅ 3-Year Fault-Free Warranty – Unmatched protection, covering failures caused by accidents, neglect, or manufacturer defects. ✅ OEM-Compatible Design – Bolt-on replacements requiring no modifications. ✅ Marine-Grade Alloy Construction – Ensuring durability, smooth operation, and longevity. ✅ Fully Assembled & Ready to Install – Reducing downtime and making installation easy.

🔍 Popular Sterndrive Parts Available:

🚤 Inboard & Outboard Engine Parts – Performance & Reliability

A boat engine is the heart of any vessel. BoatPartsBay provides access to a vast selection of inboard and outboard engine parts for gasoline and diesel-powered boats. Engine components compatible with MerCruiser, Volvo Penta, Yamaha, Suzuki, Honda, Evinrude, and Johnson make it easy to maintain, repair, or upgrade marine engines.

🛠️ Engine Parts Available:

• Fuel Systems: Carburetors, fuel injectors, fuel pumps, filters

• Ignition & Electrical: Spark plugs, alternators, starters, power packs

• Cooling Systems: Impellers, raw water pumps, thermostats, heat exchangers

• Gaskets & Seals: Complete gasket sets, head gaskets, oil seals

• Exhaust & Intake: Manifolds, risers, mufflers, air filters

⛵ Marine Accessories – Everything for Your Boat in One Place

BoatPartsBay also connects customers with a full range of boat accessories to enhance time on the water. From safety equipment to electrical upgrades, everything needed to keep a vessel safe, functional, and comfortable is available.

🚤 Top-Selling Accessories:

• Boat Maintenance Supplies – Oils, lubricants, fuel additives

• Marine Electrical Components – Batteries, navigation lights, bilge pumps

• Safety Equipment – Life jackets, first aid kits, fire extinguishers

• Anchoring & Docking – Ropes, chains, cleats, fenders

❓ Extensive FAQ – Technical & General Questions

❓ What brands are compatible with available boat parts?

Available parts are compatible with Mercury, Yamaha, Volvo Penta, Honda, Suzuki, Evinrude, Johnson, and more.

❓ What is the 3-Year Fault-Free Warranty on sterndrive units?

This warranty covers lower units and some electrical parts. There is a fault free warranty.

❓ Are outboard lower units pre-filled with gear oil?

No, customers must add the appropriate marine gear oil before installation.

❓ What sterndrive models are supported?

• MerCruiser Alpha One Gen I & Gen II

• Bravo One, Bravo Two, Bravo Three

• Volvo Penta SX, DP-S

• OMC Cobra

• Yamaha sterndrive replacements

❓ Do sterndrive units come with shift shafts pre-installed?

Yes, sterndrive units are fully assembled and include pre-installed shift shafts.

❓ Can I use aftermarket props with these sterndrives?

Yes, sterndrives are designed to accept standard aftermarket and OEM propellers.

❓ Is the water pump included with sterndrive lower units?

Yes, all sterndrive lower units include a pre-installed water pump.

❓ How can I find the correct engine part for my boat?

Use the Part Finder Tool, check the Engine Diagrams, or contact customer support for assistance.

🌊 Get Back on the Water with BoatPartsBay!

Boaters deserve the best parts at the best prices. Whether replacing a sterndrive, upgrading an engine, or enhancing boat safety, the right parts are available to order now. Enjoy fast shipping, expert support, and unbeatable warranties!

BoatPartsBay – Your Source for Marine Parts & Accessories! 🚤⚓