What to Know About a 50 HP Mercury 2-Stroke Outboard

If you're searching for a 50 hp mercury outboard 2 stroke, it's important to know that Mercury Marine stopped producing 2-stroke engines in this horsepower range nearly two decades ago. Most models currently listed under this name are either used units or mislabeled 4-stroke versions. This guide will walk you through the history of Mercury’s 50 hp 2-stroke outboards, explain their key features and limitations, compare them with modern 4-stroke alternatives, and help you make an informed decision whether buying a used 2-stroke is practical or if upgrading to a current-generation 4-stroke makes more sense for your boating needs.

Why the 50 HP Mercury 2-Stroke Is No Longer in Production

Mercury Marine phased out its traditional 2-stroke outboard motors by the early 2000s due to increasingly strict environmental regulations, particularly those related to emissions and fuel efficiency. The classic 50 hp mercury outboard 2 stroke carbureted model was last widely available around 2005 and has since been replaced by cleaner, more efficient 4-stroke technology.

The shift wasn’t unique to Mercury—it affected the entire marine industry. Two-stroke engines, while powerful and lightweight, were known for higher hydrocarbon emissions and oil mixing requirements, which led to pollution concerns in lakes, rivers, and coastal areas. As a result, many U.S. states and international regions began restricting or banning high-emission marine engines.

⚙️ Key takeaway: If you’re looking at a ‘new’ 50 hp Mercury 2-stroke today, it’s likely a used engine from the early 2000s or mistakenly labeled as such online. Genuine new production ceased long ago.

Identifying Original 50 HP Mercury 2-Stroke Models

Before they were discontinued, Mercury offered several variants of the 50 hp 2-stroke outboard. These included both tiller-controlled and remote-steering options, typically with a 20-inch (L) shaft length, suitable for medium-sized aluminum boats, pontoons, and small fishing vessels.

📌 Common identifiers for original models include:

Model numbers: 50 ELPT, 50 EFI TLPT, or earlier carbureted versions like 50 RX
Fuel system: Carbureted (pre-1996) or Electronic Fuel Injection (EFI) starting in the late 1990s
Shaft length: Standard long shaft (20 inches), sometimes referred to as 'L' model
Starting method: Electric start only on later models; pull-start versions existed on base trims
Weight: Approximately 235–255 lbs depending on configuration

🔧 One notable feature of the late-generation 50 hp Mercury 2-strokes was the introduction of Optimax direct fuel injection (in higher-end models), but this was not applied to the standard 50 hp line. Instead, most used 2005 mercury 50 hp 2-stroke outboard units found today are carbureted three-cylinder engines.

Performance Characteristics of the 50 HP 2-Stroke

The appeal of the older 50 hp Mercury 2-stroke lay in its power-to-weight ratio and simplicity. Compared to early 4-strokes—which were heavier and less responsive—these 2-strokes delivered snappy acceleration and reliable performance in shallow water applications.

Feature	50 HP Mercury 2-Stroke (circa 2005)	Modern 50 HP Mercury 4-Stroke (e.g., FourStroke)
Horsepower	50 hp @ 5,000–5,600 RPM	50 hp @ 5,500 RPM
Engine Type	2-stroke, inline 3-cylinder	4-stroke, inline 4-cylinder
Fuel System	Carbureted or EFI	Electronic Fuel Injection (EFI)
Weight (dry)	~240 lbs	~415 lbs
Fuel Efficiency	Lower (~5–6 mpg at cruising speed)	Higher (~8–10 mpg)
Emissions	Higher HC/NOx output	Meets EPA Tier 3 & CARB standards
Maintenance Needs	Regular carb cleaning, oil mixing	Oil changes, valve checks every 100 hrs

⚡ While the 2-stroke provided strong mid-range punch, it lacked low-end torque compared to modern 4-strokes. It also required pre-mixing oil with gasoline (unless it had an autolube system) or relied on separate oil injection tanks, adding complexity and potential failure points.

Where to Find Used 50 HP Mercury 2-Stroke Motors Today

🛒 Since these engines are no longer manufactured, your only option is the used market. You can find listings on platforms like eBay, Boattrader.com, or regional marine dealerships specializing in outboard repairs and resale.

📍 Some users report seeing used 50 hp mercury 2-stroke for sale near me via local classifieds or marina bulletin boards. Prices vary significantly based on condition, age, hours of use, and whether the engine has undergone recent servicing.

📌 As of 2024–2025 data from various sellers, typical price ranges for used 50 hp Mercury 2-strokes are:

Fair condition (unverified hours): $1,800 – $2,800
Good condition (serviced, lower hours): $2,800 – $3,700
Excellent/restored: Up to $4,200 (rare)

⚠️ Be cautious: Many listings titled “50 hp mercury outboard 2 stroke” actually refer to 4-stroke models. Always verify the model number (e.g., 50ELPT vs. 50ELHPT) and ask for service records. A true 2-stroke will lack the large cam cover typical of 4-strokes and have simpler exhaust routing.

Pros and Cons of Choosing a Used 2-Stroke Over a New 4-Stroke

When considering whether to buy a used 50 hp Mercury 2-stroke versus investing in a new 4-stroke, weigh the following factors carefully.

✅ Advantages of the 2-Stroke

Lower initial cost: Can save thousands over a new 4-stroke (which starts around $7,000).
Lightweight: Easier to mount on smaller transoms or lightweight dinghies.
Simplicity: Fewer moving parts than a 4-stroke; easier DIY maintenance for experienced owners.
Proven reliability: When properly maintained, these engines often last 1,000+ hours.

❗ Drawbacks of the 2-Stroke

No manufacturer support: Limited access to new OEM parts; some components may be obsolete.
Fuel inefficiency: Burns more gas per mile, increasing operating costs.
Environmental restrictions: Banned or restricted in certain waterways (e.g., Lake Tahoe, parts of Europe).
Noise and vibration: Louder operation and rougher idle than modern 4-strokes.
Resale value: Harder to sell later due to declining demand.

🔍 In contrast, a new Mercury 50hp FourStroke offers quieter operation, better fuel economy, lower emissions, and full warranty coverage (typically 3 years). However, it comes with nearly double the weight and a much higher purchase price.

How to Evaluate a Used 50 HP Mercury 2-Stroke Before Buying

If you decide to pursue a used 2-stroke, follow these steps to avoid costly mistakes.

Verify the model and serial number: Cross-check with Mercury’s official documentation or contact a dealer to confirm it’s truly a 2-stroke.
Inspect for corrosion: Saltwater exposure accelerates wear, especially in lower units and cooling passages.
Check compression: A professional should perform a compression test—values below 90 psi per cylinder indicate internal damage.
Review maintenance history: Look for records of water pump replacements, carburetor rebuilds, and gear lube changes.
Test run (if possible): Listen for knocking, smoking, or hesitation during acceleration.
Examine fuel system: Old fuel lines, degraded carbs, and varnish buildup are common issues after long storage.

🧰 Tip: Bring a marine mechanic or knowledgeable friend when inspecting. Even a $100 inspection fee can prevent a $2,000 mistake.

Are There Any Modern Alternatives That Keep the 2-Stroke Spirit Alive?

While Mercury no longer produces conventional 2-strokes, they did develop advanced direct-injected 2-stroke engines under the Optimax line—but those started at 150 hp and above, far beyond the 50 hp category.

Today, the closest thing to a lightweight, powerful alternative is Mercury’s Command Thrust version of the 50 hp FourStroke. Despite being a 4-stroke, it uses a larger-diameter propeller and optimized gearcase to improve low-speed thrust—ideal for pontoon boats and heavy loads.

✨ Features of the Mercury 50 HP FourStroke Command Thrust:

Better low-end torque than standard 4-strokes
Available with tiller or remote control
Dual-battery support and integrated alternator (25A)
Compatible with SmartCraft gauges and diagnostics
Priced between $7,500 and $8,800 new

This model doesn’t match the lightness of the old 2-stroke, but it delivers smoother performance, meets all emissions laws, and comes with modern conveniences like electric start, choke-free cold starting, and improved durability.

Common Misconceptions About 50 HP Mercury 2-Stroke Engines

Several myths persist about these older engines. Let’s clarify them.

❌ Myth 1: "All 50 hp Mercurys are 2-strokes"

No. Since the mid-2000s, Mercury has primarily produced 4-stroke engines in this class. Many people confuse model names like “50ELPT” across generations.

❌ Myth 2: "2-strokes are cheaper to maintain"

Not necessarily. While simpler, worn carburetors, failing fuel pumps, and seized pistons from poor fuel mix can lead to expensive repairs. Parts scarcity also drives up labor costs.

❌ Myth 3: "They’re banned everywhere"

False. While some ecologically sensitive areas restrict 2-strokes, many inland lakes and private waters still allow them. Always check local regulations before operation.

❌ Myth 4: "You can convert a 2-stroke to 4-stroke"

Not feasible. The internal architecture is completely different. Conversion kits do not exist.

Final Recommendation: Should You Buy a 50 HP Mercury 2-Stroke?

The answer depends on your specific situation.

👥 Consider a used 50 hp mercury outboard 2 stroke if:

You need a budget-friendly engine for occasional use.
Your boat is lightweight and already balanced for a lighter motor.
You have mechanical skills or access to a trusted mechanic.
You operate in unrestricted waters where emissions aren’t monitored.

✅ On the other hand, choose a new 4-stroke if:

You want reliability, warranty, and consistent performance.
You boat frequently or rely on the engine for safety.
You plan to keep the boat long-term or resell it.
You operate in regulated or environmentally sensitive areas.

📌 Ultimately, the 50 hp Mercury 2-stroke represents a legacy technology—one that served countless boaters well but has been superseded by cleaner, more efficient designs. Its availability today is limited, and ownership requires diligence. But for the right user, it remains a viable entry-level option.

Frequently Asked Questions

❓ Can I still register a 50 hp Mercury 2-stroke outboard?: Yes, in most U.S. states, existing 2-stroke engines can still be registered unless specifically banned by local law (e.g., California CARB rules for certain lakes). Always verify with your state’s Department of Natural Resources or equivalent agency.
❓ How many hours is too many on a used 50 hp Mercury 2-stroke?: A well-maintained 2-stroke can last 1,000–1,500 hours. Engines exceeding 1,200 hours without major service may require significant investment. Anything over 1,500 hours should be inspected thoroughly before purchase.
❓ What kind of oil should I use in a 50 hp Mercury 2-stroke?: Use TC-W3 certified two-stroke marine oil. Mercury recommends their own formulation, but other reputable brands (like Yamaha Yamalube or Quicksilver) are compatible. Do not use automotive 2-cycle oils.
❓ Is there a replacement impeller part number for the 2005 Mercury 50 hp 2-stroke?: Yes, the standard water pump kit for most 50 hp Mercury 2-strokes (20" shaft) uses part number 18-4347-1 (OEM) or equivalent aftermarket kits. Confirm fitment using your engine’s serial number.
❓ Why are some 50 hp Mercury outboards so much cheaper online?: Lower-priced units are often sold “as-is,” with unknown maintenance history, high hours, or saltwater corrosion. Some listings exclude controls or mounting hardware. Always ask what’s included before bidding or buying.