The Mercury Racing SST-120 V6 2-Liter outboard  is a legendary engine in tunnel boat racing, celebrated for its performance, reliability, and advanced engineering. Designed for the Formula 2 (SST-120) racing circuit, this engine, introduced in the late 1980s, has powered numerous racers to victory and remains a sought-after choice for both competitive and recreational use. Its lightweight design, high RPM capability, and dependable construction made it the backbone of Formula 2 racing, setting a standard for performance in the sport. Even today, the SST-120 is prized by active racers, outdoor drag racers, and tuners who appreciate its enduring appeal and potential for modification. In a new development, Buckshot Racing #77 is posting the race porting specifications diagram  for the SST-120 available to tuners, hobbyists, and outdoor drag racers. While these specs are already familiar to professional SST-120 teams, this initiative provides those outside the professional circuit with detailed insights into the optimal dimensions and timings for rebuilding and modifying their Mercury 2.0-Liter outboards, including the AA Fat Blocks, earlier XR2 2.0 Liters and the original 1976-1977 1750 Black Max. These porting specifications offer tuners and enthusiasts a chance to maximize the performance of their engines, whether for drag racing, restoration projects, or recreational competition. By providing this information, Buckshot Racing hopes to empower the broader racing and tuning community, ensuring that the SST-120 continues to perform at its peak for years to come. The SST-120 was designed as a 60° V6, 2-stroke outboard with a displacement of 2.0 liters (122 cubic inches), a bore and stroke of 3.125 inches by 2.65 inches, and a compression ratio of 10.0:1. It produces approximately 190-215 HP and operates at up to 7,500 RPM, making it ideal for high-speed racing applications. The engine uses a dual-throat carburetor for fuel delivery, paired with a high-performance electronic CDI ignition system for precise and reliable timing. It runs on a 32:1 fuel mixture of high-octane racing fuel and 2-stroke oil, with a water-cooled system to maintain consistent performance under demanding conditions. Weighing approximately 330 pounds, the SST-120’s compact design enhances aerodynamics and handling, particularly in tunnel boat configurations. The SST-120 is built for high RPM performance, ensuring exceptional speed and acceleration during races. Its lightweight design contributes to a superior power-to-weight ratio, while the precision ignition and optimized cooling system allow it to handle the intense demands of competitive racing. These features have made it a standout in its class, solidifying its reputation as a reliable and high-performing engine. The legacy of the SST-120 is undeniable. Its influence on the competitive Formula 2 scene and continued use in vintage and amateur racing reflect its lasting value. For tuners, hobbyists, and outdoor drag racers, the availability of porting specifications offers an exciting opportunity to push the boundaries of what this iconic engine can achieve. Mercury Racing’s SST-120 remains a testament to the company’s dedication to innovation and performance, providing enthusiasts with a compelling mix of history, engineering excellence, and ongoing relevance. Download the full Mercury SST-120 Tech Specs from the American Powerboat Association (APBA) Outboard Performance Craft (OPC) UIM Homologation Race Parts for the SST-120

Analysis of the 7 Mercury Racing APX Gear Ratios with an 18-Pitch Propeller and 20% Slip We conducted a theoretical analysis to examine the performance of Mercury Racing APX Outboards (200 V6, 250 V8, and 360 V8 models) and the seven (7) available OEM gear ratios from the Factory. These gears can be changed in the overdrive box! We factored in the 1.13 final drive ratio found in the current SuperSpeed Master #4 (SSM4) drive, an 18-pitch propeller, and a typical 20% propeller slip found on F1 Tunnel Boats. The impact of these configurations on speed and torque provides insights for optimizing race setups. Mercury Racing APX Gear Ratios and Performance Data The table below presents the adjusted gear ratios, peak propeller shaft speeds, and calculated top speeds for V8 and V6 engines: Gear Ratio Overall Ratio (1.13) Peak Prop Shaft Speed (V8) Peak Prop Shaft Speed (V6) Top Speed (V8, mph) Top Speed (V6, mph) 0.667 0.754 9,259 9,055 126.26 123.48 0.714 0.807 8,756 8,564 119.40 116.78 0.724 0.818 8,672 8,483 118.25 115.68 0.739 0.835 8,483 8,302 115.68 113.21 0.765 0.864 8,191 8,024 111.70 109.42 0.786 0.889 7,987 7,823 109.05 107.00 0.818 0.926 7,718 7,551 105.85 103.55 Key Findings Maximizing Top Speed : The 0.667 gear ratio  delivers the highest top speed for both V8 and V6 engines, reaching 126.26 mph (V8)  and 123.48 mph (V6) . This configuration is best for flat-water or top speed racing. Prioritizing Torque and Acceleration : Higher gear ratios like 0.765 , 0.786 , and 0.818  provide more torque at the expense of top speed. These configurations excel in rough water or technical courses requiring rapid acceleration and precise handling. Balanced Configurations : Ratios such as 0.724  and 0.739  (Stock on the APX 360) offer a balance of speed and torque, making them suitable for circuits with mixed conditions, including straights and tight turns. Effect of the 1.13 Final Drive Ratio : The final drive ratio slightly reduces prop shaft speeds to better match prop speeds found on the legacy 2-stroke S3000, F1 and SST-120 while enhancing durability and efficiency, ensuring consistent performance under demanding conditions. Practical Applications for Racers Top Speed : For straight-line speed dominance, the 0.667  gear ratio is ideal, especially in calm water with minimal resistance. Technical Race Courses : In courses with sharp turns or rough water, ratios like 0.786  or 0.818  (Stock on the APX 200 V6 and APX 250 V8) improve acceleration and cornering capabilities. Class-Restricted Competitions : The APEX 200/250  engines with the 0.818 ratio  provide dependable torque for restricted power classes, while the APX 360 with the 0.739  thrives in high-performance scenarios with lower gear ratios. Overdrive Gear Teeth Count 0.667  (30:20) 0.714  (35:25) 0.724  (29:21) 0.739  (23:17) Homologated for V8 360 APX 0.765  (34:26) 0.786  (28:22) 0.818  (22:18) Homologated for the V6 200 & V8 250 APX The teeth count is required for APBA US F1, F200, F150, Champ and UIM F1H20 Tech Inspection. For instance, the 250 APX is currently legal to only run the 22 tooth and 18 tooth gear set. Special Event races may allow other gear set combinations. Conclusion The choice of gear ratio is critical for achieving the desired balance of speed and torque. With an 18-pitch propeller and 20% slip, racers can fine-tune their Mercury Racing APX outboards to excel in specific racing conditions. By leveraging the insights from this analysis, crew chiefs and boat racers can optimize their configurations for maximum performance and competitive advantage. Check out our New DDT Scan Tool for the APX 200, 250, and 360!

The first 10 hours are the most important hours of your new 2-stroke Mercury, OMC, and Yamaha life. Engine Oil & Fuel Double the oil quantity with an approved non-synthetic TCW-3 oil. Increase fuel mixture to rich Use 91 to 93 octane premium fuel or higher for high compression heads. Avoid products that have alcohol additives, or chemicals that may alter the fuel condition. Initial Break-in & Warm-up Allow for four (4) hours for break-in of a new piston and/or rings at idle speed, keeping the engine under 3,500 rpms. For the first 10 hours, avoid continuous full throttle. Ensure the engine reaches normal operation temperatures to avoid cold seizure that results from the piston expanding faster than the cylinder liner (which is being liquid-cooled). RPM Guidelines For hour five (5), after warm-up, operate the engine in gear at approximately 1,500 RPM for the first twenty minutes. For the remaining forty minutes, operate the engine in gear no more than three thousand RPM. Use only enough throttle to plane the boat, then immediately throttle back to less than three thousand RPM. For the sixth hour, accelerate enough to bring the boat up on the plane quickly, and bring the throttle back to maintain the boat up on the plane. During this period, vary your engine speed by accelerating to 3/4 throttle for a minute or two, then back to minimum planning speed. Do NOT run at constant RPM for prolonged periods. For the next four hours of operation, continue to cruise at approximately 3/4 throttle or less at minimum planning speed. Occasionally reduce the throttle to idle speed for the cooling period. During the final hours, you may operate the boat at wide open throttle for periods of less than two minutes. These are general break-in procedures that may vary from OEM guidelines and our race program. Always refer to the OEM service manual for the most model-specific break-in procedures and guidelines.

Mercury Outboard 2-Stroke V6 Power Trim Cylinder Repair Kit Installation Guide This detailed rebuild guide will walk you through the process of using the Buckshot Racing #77 Repair Kit for the Mercury Outboard 2-Stroke V6 Power Trim Cylinder, replacing the more expensive Mercury Mariner OEM part number 79879A1 kit. Ensure you work in a clean, lint-free environment to prevent contamination of hydraulic components. Tools Required: Spanner wrench Suitable container for draining oil Non-toxic solvent Compressed air Loctite “271” Torque wrench (58-72 ft. lbs.) Disassembly Instructions: Preparation: Disconnect the hydraulic hoses from the power trim cylinder as described in the Mercury Outboard service manual. Drain Hydraulic Oil: With the trim cylinder removed, direct the up and down ports into a suitable container. Push the trim rod in and out several times to drain the oil completely. Remove Trim Rod Assembly: Using a spanner wrench, unscrew the rod guide and pull the trim rod assembly out of the cylinder. Extract Floating Piston: Remove the floating piston by tapping the open end of the cylinder on a block of wood. Discard the old O-ring from the piston. Disassemble Shock Piston: Unscrew the bolt from the trim rod end. Remove the large washer and shock piston assembly. Extract the two O-rings, compression springs, spring guides, spring seats, and check balls. Discard the old O-rings. Remove Rod Guide Components: Take off the rod guide from the trim rod. Remove and discard the retaining ring, plain washer, scraper, and three O-rings from the rod guide. Clean All Components: Use a non-toxic solvent to clean all parts thoroughly. Dry each component with compressed air before reassembly. Reassembly Instructions: Prepare Rod Guide: Lubricate all internal parts with SAE 10W-30 or 10W-40 motor oil. Install three new O-rings (from the kit) onto the rod guide. Install the new scraper, plain washer, and retaining ring. Slide the rod guide over the end of the trim rod. Rebuild Shock Piston: Install the check balls, spring seats, compression springs, and spring guides into the shock piston. Install two new O-rings from the kit onto the shock piston. Assemble Trim Rod: Place the shock piston and large washer onto the end of the trim rod. Apply Loctite “271” to the piston rod bolt threads. Tighten the bolt into the piston rod to a torque specification of 58-72 ft. lbs. (8.02-9.95 mkg). Install Floating Piston: Fit the new O-ring from the kit onto the floating piston. Insert the piston into the cylinder with the blunt end first. Final Assembly: Insert the trim rod assembly into the trim cylinder. Thread on the rod guide and tighten securely. Post-Rebuild Steps: Reconnect the hydraulic hoses. Refill the hydraulic system with the manufacturer-recommended fluid. Bleed the system to remove air pockets. Test for smooth operation and check for leaks. Mercury Long Ram Rebuild Instructions - Free PDF Download

The Birth and Evolution of the Outboard Engine: A Legacy of Innovation and Nostalgia The tale of the outboard engine begins with a moment of simple frustration. In the summer of 1907, Norwegian-American inventor Ole Evinrude was picnicking with his wife, Bess, on the shores of Okauchee Lake in Wisconsin. When Bess expressed a craving for ice cream, Evinrude rowed to shore, only to return with a half-melted treat. This seemingly trivial moment sparked an idea: Why not create a small motor that could propel a boat more efficiently? Evinrude, already an accomplished machinist, went to work in his shop. By 1909, he had produced the first commercially viable gasoline-powered outboard engine—a 1.5-horsepower, single-cylinder, two-stroke motor weighing around 62 pounds. It clamped onto the stern of a boat and featured a tiller for steering. Unlike previous attempts at boat motors, which were often adapted from stationary engines, Evinrude's design was purpose-built for marine use: lightweight, portable, and reliable. The Golden Age of the Two-Stroke Outboard Engine Evinrude's two-stroke engine revolutionized small boating. The simplicity of the two-stroke cycle, which completes a power stroke with every revolution of the crankshaft, offered a significant advantage over four-stroke engines of the era. The result was more power relative to weight, fewer moving parts, and easier maintenance—a perfect combination for recreational boaters and anglers. By 1911, Evinrude had sold thousands of engines and established a booming business. His success inspired competition, with brands like Elto (Evinrude Light Twin Outboard, founded by Evinrude after briefly leaving his original company), Johnson, and Atwater Kent entering the market. The 1920s and 1930s saw rapid refinement in two-stroke technology, with engines becoming lighter, more efficient, and easier to operate. Hallmarks of Early Two-Stroke Outboards: Simple Design:  With only three core components—intake, compression, and exhaust—the two-stroke cycle was mechanically straightforward and easy to service. Direct Drive:  Early models had the propeller shaft connected directly to the crankshaft, eliminating the need for complex gearing. Air and Water Cooling:  While some early models were air-cooled, water-cooled designs quickly became the standard, improving engine longevity. Race Competition Breeds Innovation (1920s–1950s) As the popularity of outboards grew, so did competition. The Johnson brothers, who founded Johnson Outboards in 1922, introduced lightweight aluminum construction, reducing engine weight without sacrificing strength. Mercury, founded by Carl Kiekhaefer in 1939, further pushed the envelope with streamlined designs and more powerful models. Two-stroke technology dominated this era, with manufacturers focusing on improving fuel delivery, ignition systems, and cooling efficiency. The introduction of the forward-neutral-reverse (F-N-R) gearshift was a game-changer, allowing boaters to maneuver more precisely. During World War II, military demand for portable marine engines drove further innovation. After the war, these advancements filtered into the recreational market, sparking a post-war boom in outboard sales. Nostalgic Icons: Evinrude Light Twin:  Known for its reliability and ease of use, this engine became a favorite among anglers and families. Johnson Sea Horse:  Introduced in the 1930s, the Sea Horse line became synonymous with quality and performance. Mercury Hurricane:  A high-performance two-stroke that set new speed records in the 1940s. The 1950s and 1960s marked the golden age of recreational boating in America. Middle-class families embraced leisure time on the water, and the outboard engine became a fixture on lakes, rivers, and coastal waters. Manufacturers raced to produce engines that were not only powerful but also stylish, with chrome accents, pastel colors, and streamlined cowlings. Two-stroke engines reigned supreme, thanks to their affordability, light weight, and ease of maintenance. Innovations during this period included: Electric Start:  No more yanking on a rope—turning a key became the norm. Remote Controls:  Throttle and steering controls moved from the tiller to the helm. Improved Fuel Systems:  Carburetor refinements and oil injection systems reduced smoke and improved efficiency. Outboard motors were no longer just tools—they were lifestyle accessories. Brands like Evinrude, Johnson, and Mercury sponsored boat races, further fueling public fascination with speed and power on the water. The Soul of the Two-Stroke: Sound, Smoke, and Simplicity For many enthusiasts, the two-stroke outboard represents more than just an engine—it's a sensory experience. The distinctive pop-pop-pop  of an idling two-stroke, the faint haze of blue smoke on a calm morning, and the unmistakable aroma of burned oil and gasoline evoke memories of summer days spent fishing, skiing, or exploring quiet coves. Though simple, two-stroke engines required a certain mechanical intimacy. Owners mixed their own fuel, tinkered with carburetors, and became adept at diagnosing minor issues. It was a hands-on era, where understanding your engine was part of the boating experience. By the 1980s, environmental concerns and fuel efficiency standards began to challenge the dominance of the two-stroke engine. Traditional two-strokes, while lightweight and powerful, were inherently inefficient—expelling unburned fuel with exhaust gases. In response, manufacturers introduced oil injection systems, leaner carburetors, and, eventually, direct fuel injection (DFI) systems, such as Evinrude’s iconic E-TEC line. Yet, even as four-stroke technology gained traction, two-stroke engines retain a devoted following till today. Their simplicity, power-to-weight ratio, and nostalgic charm kept them alive, especially among anglers, racers, and vintage enthusiasts. The story of the outboard engine is more than just a tale of mechanical evolution; it's a narrative woven into the fabric of recreational boating. It’s the thrill of the first pull-start on a foggy morning, the laughter of children being towed on an inflatable tube, and the quiet satisfaction of a well-tuned engine purring at idle. While modern technology has pushed outboards into new realms of efficiency and complexity, the heart of the outboard engine—the spirit of adventure and innovation first ignited by Ole Evinrude—lives on in every ripple left behind by a spinning propeller. And for those who still live the golden age of the two-stroke, that sound will always be the song of summer.

While the Buckshot Racing #77 Speed Store remains fully committed to maintaining high-performing 2-stroke outboards, it's noteworthy that most 2-stroke models are no longer in production. For the 2025 model year, Mercury Racing introduces a robust lineup of eleven 4-stroke high-performance outboard engines, specifically engineered for recreational boating and competitive racing enthusiasts. Below is a comprehensive list of the 2025 Mercury Racing outboard models, comprising seven in the R-Series and four in the Competition Series: R-Series Outboards: Designed for high-performance recreational boating, the R-Series engines deliver exceptional power and acceleration. Mercury Racing 500R Horsepower:  500 HP Engine Type:  4.6L V8 Supercharged Dry Weight:  726 lbs Features:  The 500R offers elevated power and technology, featuring a new 4.6L V8 powerhead with upgraded components, increased supercharger boost pressure, and an Advanced Racing Core (ARC) midsection for enhanced durability and performance. Mercury Racing 400R Horsepower:  400 HP Engine Type:  5.7L V10 Dry Weight:  695 lbs Features:  The 400R sets a new standard of performance with advanced features, custom graphics, and a wide range of parts compatibility, making it suitable for various high-performance boating applications. Mercury Racing 300R Horsepower:  300 HP Engine Type:  4.6L V8 Dry Weight:  512 lbs Features:  The 300R is tuned with Mercury Racing components to deliver crisp throttle response and thrilling top-end power. It offers multiple midsection and gearcase options to tailor performance to specific applications. Mercury Racing 250R Horsepower:  250 HP Engine Type:  4.6L V8 Dry Weight:  520 lbs Features:  The 250R provides class-leading performance with a 10% increase in fuel efficiency, offering a lower cost of ownership without compromising on power. Mercury Racing 200R Horsepower:  200 HP Engine Type:  2.6L V6 Dry Weight:  469 lbs (torq master) 489 lbs (sportmaster) Features:  The 200R delivers robust performance in a compact package, ideal for smaller high-performance boats requiring a balance of power and agility. Mercury Racing 150R Horsepower:  150 HP Engine Type:  3.4L V6 Dry Weight:  475 lbs Features:  The 150R is the perfect entry point for sophisticated boaters seeking the performance and luxury refinement of Mercury Racing R-Series power. It features a smooth and efficient V6 powerhead coupled with advanced Digital Throttle & Shift (DTS) control capability. Mercury 60R Horsepower:  60 HP Engine Type:  1.0L L4 Dry Weight:  268 lbs Features:  The 60R is built with speed in mind, designed specifically for technical flats skiffs to deliver performance with outstanding fuel economy, rugged reliability, and quiet operation. Mercury Racing R-Series Competition Series Outboards: Engineered for professional racing, the Competition Series outboards are designed to meet the rigorous demands of competitive tunnel boat powerboat racing. Mercury Racing 360 APX Horsepower:  360 HP Engine Type:  4.6L V8 Dry Weight:  430 lbs Features:  The 360 APX is a potent competition outboard designed specifically to power Formula One tunnel boats in the premier class of the UIM F1H2O World Championship. It delivers impressive torque from a durable, low-emissions four-stroke V8 powerhead that sets a new benchmark for circuit-racing performance. Mercury Racing 250 APX Horsepower:  250+ HP Engine Type:  4.6L V8 Dry Weight:  436 lbs Features:  The 250 APX joins the competition portfolio to open a new competitive era in APBA Formula 1 and UIM F2 powerboat racing. It is tuned to deliver race-winning torque and acceleration combined with outstanding durability and a cost-effective, race-winning advantage over legacy two-strokes. Mercury Racing 200 APX Horsepower:  200+ HP Engine Type:  3.4L V6 Dry Weight:  395 lbs Features:  The 200 APX is a powerful V6 four-stroke outboard designed for UIM F2 and APBA OPC tunnel boat racing. It offers racers a very durable powerhead and the latest in four-stroke engine technology, while reducing exhaust emissions by 90 percent compared to legacy two-stroke competition outboards. Mercury Racing 60 APX Horsepower:  60 HP Engine Type:  1.0L L4 Dry Weight:  247 lbs Features:  The 60 APX is designed specifically for up-and-coming racers competing in UIM Formula 4 class competition. It has been expertly tuned to run at a wide-open throttle limit of 6000-6400 rpm, delivering all the adrenaline of the legendary Apex competition series in a lightweight, compact package. Mercury Racing APX Series Mercury Racing's dedication to innovation and performance is evident in both their R-Series and Competition Series outboards, catering to the needs of high-performance boating enthusiasts and professional racers alike.

How to Use an Ethanol Fuel Tester for Legacy Mercury, Yamaha, OMC, Johnson, Evinrude, and Tohatsu 2-Stroke Outboards Using an Ethanol Fuel Tester  is crucial for maintaining the fuel quality in legacy two-stroke outboards  from Mercury, Yamaha, OMC, Johnson, Evinrude, and Tohatsu is a best practice . Ethanol causes fuel separation, varnish (sticky tar) buildup, and damage to carburetors, fuel lines, and seals , making it essential to check ethanol content before use. Step-by-Step Guide to Testing Ethanol in Your Fuel What You’ll Need: ✔ Ethanol Fuel Tester  (a clear graduated test tube with ethanol percentage markings) ✔ Gasoline sample  (from your fuel tank, gas can, or station pump) ✔ Water  (preferably distilled for accuracy) Instructions: 1. Fill the Tester with Water Locate the water fill line  near the bottom of the tester. Pour clean water  up to the indicated line. 2. Add Your Gasoline Sample Slowly pour your fuel sample  into the tester until it reaches the gasoline fill line  (usually near the top). Avoid overfilling or spilling. 3. Seal and Shake the Tester Secure the cap  tightly. Shake the tester gently  for 30-60 seconds  to mix the gasoline and water. Set the tester on a flat surface and allow the fuel to separate. 4. Let the Fuel Settle Wait about 5-10 minutes  for separation to occur. The water will pull the ethanol from the gasoline , settling at the bottom. The pure gasoline will remain on top. 5. Read the Ethanol Content Check the new water level  after settling. The increase in water volume represents the percentage of ethanol in your fuel . Example: If the water level rises to the 10% mark , your fuel contains 10% ethanol (E10) . Interpreting Your Test Results for Legacy 2-Stroke Outboards ✅ 0% (E0)  – Ethanol-free fuel  (best for legacy two-stroke engines, prevents carburetor issues). ✅ Up to 10% (E10)  – Most outboards can tolerate this  but require fresh and proper fuel blends or additives. ⚠ Above 10% (E15, E20, E85, etc.)  – Not recommended for older two-stroke outboards , as it can cause fuel phase separation, lean running conditions, and engine damage . Why Legacy 2-Stroke Outboards Need Ethanol Testing Prevents fuel breakdown  that leads to carburetor blockages. Reduces risk of fuel line degradation  caused by ethanol. Ensures proper fuel/oil mixture stability  for smooth performance. Avoids phase separation , which can cause hard starts, poor idling, and engine stalling . Protects seals and gaskets  in vintage Mercury, Yamaha, OMC, Johnson, Evinrude, and Tohatsu  two-stroke engines. Recommended Fuel Options for Legacy 2-Stroke Outboards To maintain optimal performance and longevity, using recreational (REC) non-ethanol pump gas (typically 89 or 90 Octane), race fuels, or a blend of these fuels  is highly recommended. Non-ethanol fuel  eliminates the risks of phase separation, corrosion, and degradation  commonly associated with ethanol-blended fuels. Race fuels  provide higher octane stability , which can benefit high-performance applications. A custom blend  of non-ethanol pump gas and race fuel can offer a balance of affordability, protection, and performance , ensuring smooth operation for legacy two-stroke marine engines . By regularly testing ethanol content and selecting the right fuel, you can extend the life of your outboard engine , maintain peak performance , and reduce costly carb rebuilds, fuel injector cleaning service fuel system and fuel line replacements and repairs . 🚤⚙️🔧

High-performance mechanics and tuners often like to remove the Oil Injection System from their Mercury 2-Stroke V6 Outboard due to its known tendency to fail and its unreliability above 6400 rpm. To install our Oil Injection Block-Off Kit on the Mercury 2.0, 2.4, 2.5 Liter outboards (compatible with part numbers 818304-A1, 8M0095447, 43453, 43453T, and 32509) on your outboard engine, follow these detailed steps: Tools and Materials Needed: Oil Injection Block-Off Kit (includes block-off plug, O-ring, and mounting screws) Screwdrivers (Phillips and flathead) Socket set with ratchet Clean rags Marine-grade sealant Procedure: Safety Precautions: Disconnect the battery to prevent accidental engine starts. Shut off any fuel lines disconnects Ensure the engine is cool and in a well-ventilated area. Drain Oil: Remove oil from the oil lines and the oil tank to prevent spills during the installation process. Access the Oil Pump: Remove any covers or obstacles obstructing access to the oil pump. Refer to your engine's service manual for specific disassembly instructions. Disconnect Oil Lines: Carefully disconnect all oil lines from the pump. Plug or cap the lines to prevent oil leaks or contamination. Remove the Oil Pump: Unbolt the oil pump from the engine block using the appropriate socket or wrench. Remove bolts, pump, or-ring, long gear drive, and sleeve. Install the Block-Off Plate: Clean the mounting surface to remove old gasket material and debris. Align the block-off plate from the kit over the oil pump mounting area. Apply a light bead of marine-grade sealant around the O-ring area. Secure the block-off plate with the bolts provided in the kit. Be careful; over-tightening the bolts could crack the cap. Reassemble and Final Steps: Inspect all connections and ensure everything is properly secured. Reinstall any covers or components removed during disassembly. Drain and Refill your fuel tank with the appropriate type and amount of pre-mixed fuel (24:1 to 50:1 fuel-to-oil ratio). Reconnect the battery cables and ensure a secure connection. Start the engine and let it run briefly to ensure there are no leaks around the block-off plate. Additional Considerations: Over-Temperature Alarm:  After removing the oil injection system, it's crucial to ensure that the over-temperature alarm remains functional. The warning alarm system typically has two modes: a constant alarm indicating an over-temperature problem and a pulsing alarm indicating an oil injection problem. When you disable the oil injection system, the pulsing alarm will no longer function, but the over-temperature alarm should still work. To test this, locate the Tan/Blue wire that was connected to the warning module. Grounding this wire with the ignition on should trigger the over-temperature alarm, confirming its functionality. Oil Injection Warning Module:  You can choose to remove the oil injection warning module entirely or leave it in place. If you decide to remove it, disconnect all associated wiring and cap the wires to prevent short circuits. Crankshaft Gear:  It's advisable to keep the old oil pump gear on the crankshaft, as it provides crankcase volume. Removing it may cause that cylinder to run lean. Labeling:  After converting to pre-mixed fuel, place clear labels near the fuel fitting on the motor, the dashboard, and the fuel fill fitting on the boat to alert operators that the gas requires oil to be added. By following these steps and considerations, you can successfully install the Mercury Oil Injection Block-Off Kit and transition to a pre-mixed fuel system, ensuring the continued reliable operation of your outboard engine. The complete kit is available here at Buckshot Racing 77 on the link below:

Cam2 110 Leaded Race Fuel Specs Mercury V6 2-stroke outboards are widely used in high-performance marine and boat racing applications with higher compression increases power output. Selecting the correct fuel is crucial to maintaining engine reliability and performance. CAM2 110 and other like-kind Race Fuels  are a high-octane, leaded fuel designed for high-compression, high-performance applications. This article explores why tuning a race fuel like CAM2 110 is beneficial for these motors, including compatibility, advantages, and considerations when using CAM2 110 in Mercury V6 2-stroke outboards with increased compression. Why Tune with Race Fuel? Tuning with a high-octane race fuel like CAM2 110 is essential when running higher compression in Mercury V6 2-stroke outboards. High compression, typically considered 140 psi or higher , generates more power by squeezing the air-fuel mixture tighter before ignition, but it also raises cylinder temperatures and increases the likelihood of detonation. Using a lower octane fuel can cause severe internal damage. By switching to CAM2 110, which has a (R+M)/2 octane rating of 110 , the fuel can withstand higher temperatures and pressures before igniting, preventing pre-ignition and ensuring a smoother, more controlled combustion event. This allows tuners to safely adjust timing advance  and fuel mixtures to extract more power from the engine while maintaining durability and reliability. Why Run More Ignition Timing Advance? One of the major benefits of using CAM2 110 in a high-compression Mercury V6 2-stroke is the ability to safely run more ignition timing advance  (25+ degrees). Advancing the timing increases the duration the air-fuel mixture is burning before the piston reaches top dead center (TDC), leading to more complete combustion and increased power output. However, with lower-octane fuel, advancing timing too much can lead to detonation, damaging pistons and cylinder walls. Since CAM2 110 and like-kind fuels resist detonation better than pump gas, tuners can increase timing advance in small increments , closely monitoring for signs of detonation through spark plug readings, exhaust gas temperatures (EGT), and piston wash. More ignition advance can enhance throttle response and improve mid-range torque, making the outboard more responsive in high-performance applications. How to Optimizing Fuel Blends for Performance? While CAM2 110 is excellent for high-compression setups, some users may find that blending it with 90-octane recreational non-ethanol fuel  can yield the best balance between performance, fuel economy, and cost. For example, a 50/50 mix of CAM2 110 and 90-octane fuel  results in a blend with approximately 100-octane , which may be sufficient to prevent detonation while allowing for a more aggressive ignition timing curve. Other blends include: 1:4 mix creates 96-octane which suits 140-145 psi  engines at 25 degrees timing, while 2:3 mix creates 97-octane, 3:2 blend creates 98-octane , and 4:1 mix creates 102-octane to handle even higher compression and more timing advance. Blending fuels enables tuners to dial in the ideal octane level  for a specific compression ratio and ignition timing, rather than using an unnecessarily high octane level that may not provide additional benefits. To determine the best blend, users should consider testing different ratios and monitoring spark plug color, exhaust gas temperatures (EGT), and piston wash  to ensure the engine is running at peak efficiency. Experiment at your own risk! Advantages of CAM2 110 in High-Compression Mercury V6 2-Strokes 1. Prevents Detonation & Pre-Ignition The high motor octane rating (106)  ensures stability under load, reducing the risk of detonation in high-compression setups. 2. Improved Throttle Response & Power Delivery CAM2 110 burns efficiently at high RPMs, resulting in consistent power output and reduced hesitation . 3. Zero Ethanol – Ideal for Marine Use Unlike pump gas, CAM2 110 contains 0% ethanol , eliminating fuel system corrosion and water absorption issues common in marine environments. 4. Lead Content Enhances Lubrication Lead provides additional lubrication for rings, bearings, and cylinder walls , increasing longevity in high-performance setups. Other Considerations Carburetor & Jetting Adjustments: Some tuning may be required to optimize air/fuel mixtures when switching to CAM2 110 or a blended fuel mix. Environmental Regulations: Leaded fuels are restricted in some areas; ensure compliance with local laws before using CAM2 110. Cost vs. Performance Gains: Race fuel is more expensive than pump gas; consider whether the power gains justify the cost for your application. Conclusion Utilizing CAM2 110 Race Fuel  in high-compression Mercury V6 2-stroke outboards  provides significant benefits, including increased detonation resistance, improved throttle response, and more consistent power output. However, not all setups require the full 110-octane rating , and blending CAM2 110 with 90-octane recreational fuel  can optimize performance for a given compression and ignition timing setup. Tuning is key to maximizing the advantages of race fuel, and factors such as compression ratio, ignition timing, and fuel mixture  should be carefully adjusted to achieve peak performance. By experimenting with fuel blends and proper tuning techniques , boat racers can extract maximum efficiency, reliability, and horsepower from their Mercury V6 outboard engines.

How and Why to Apply Super Lube Dielectric Grease to Spark Plug and Coil Terminals For high-performance Mercury, Yamaha, and OMC outboard engines , maintaining a strong and reliable ignition system is crucial. When replacing spark plug wires or ignition cables, applying a small amount  of Super Lube Dielectric Grease with PTFE  to the metal terminals is a simple but essential step. This grease not only protects against moisture and corrosion but also enhances long-term durability and ease of maintenance—key factors in harsh marine environments . What Does Dielectric Grease Do for Conductivity? Dielectric grease is non-conductive , meaning it does not enhance electrical conductivity. However, it improves overall connection reliability  by preventing corrosion, oxidation, and water intrusion, which can degrade ignition performance over time. Since marine engines operate in wet, sometimes salty environments , these factors are a major concern. When applied correctly, dielectric grease does not interfere with the electrical connection  because the terminals make direct metal-to-metal contact through pressure. Instead, the grease seals out moisture and contaminants , ensuring a cleaner, stronger connection that prevents misfires and high resistance. Why Use Dielectric Grease in Marine Applications? High-performance outboard engines from Mercury, Yamaha, and OMC  rely on precise ignition timing and strong spark delivery to maintain peak power. Super Lube Dielectric Grease with PTFE  plays a key role in ensuring consistent performance in these demanding conditions. What is PTFE, and Why is it Important? PTFE (Polytetrafluoroethylene)  is a high-performance synthetic fluoropolymer that enhances the lubrication and protective properties of dielectric grease. PTFE provides additional resistance against moisture, heat, and wear, making it ideal for marine ignition systems . Key Benefits of PTFE in Dielectric Grease for Outboard Motors: Enhanced Lubrication:  PTFE reduces friction in spark plug boots, making installation and removal easier. Superior Moisture Resistance:  It provides extra protection against water and salt exposure, crucial in marine environments. Longer-Lasting Protection:  PTFE increases the grease’s durability, preventing it from drying out or washing away over time. Non-Conductive and Chemically Stable:  PTFE helps maintain insulation properties while resisting degradation from fuel, oil, and heat. Should You Use a Lot or a Little? Only a small amount  of dielectric grease is needed. Using too much can cause excess grease to spread, potentially attracting dirt and interfering with the connection. A thin, even layer  provides optimal protection without affecting performance. How to Apply It Properly Clean the Terminals:  Wipe down the metal contacts on the spark plugs and ignition coils with a clean cloth or contact cleaner to remove dirt and oxidation. Apply a Small Amount:  Use a fingertip or cotton swab to apply a thin film  of Super Lube Dielectric Grease with PTFE  directly onto the metal terminals inside the spark plug boot and coil connections. Install Spark Plug Wires:  Firmly push the boots onto the spark plugs and ignition coils, ensuring a snug and secure fit. Final Check:  Confirm that all boots are fully seated to prevent misfires and water intrusion. Conclusion For Mercury, Yamaha, and OMC outboards , proper ignition maintenance is essential for peak performance and reliability in marine environments. Super Lube Dielectric Grease with PTFE  is a simple yet powerful tool that protects electrical connections , prevents corrosion , and ensures strong spark delivery —all crucial factors in high-performance marine applications. By applying a small amount  of grease to spark plug and coil terminals, you can extend the life of your ignition system and keep your engine running smoothly on the water.

Rebuild Instructions for Mercury Triple Ram Trim and Tilt System Using Buckshot Racing #77 Seal and Rebuild Kit These step-by-step instructions will guide you through the rebuilding process  of your Mercury Triple Ram Trim and Tilt system  using the Buckshot Racing #77 Seal and Rebuild Kit or Mercury OEM part numbers: 8116121 (NLA), 811612, 811612-A1, 811612-A2, and later 811612-A3. This guide covers removal, disassembly, seal replacement, and reassembly  to restore proper function to your hydraulic system. Tools & Materials Required ✔ Buckshot Racing #77 Seal and Rebuild Kit ✔ Socket Set & Ratchet (Metric & SAE) ✔ Wrench Set ✔ Screwdrivers (Flathead & Phillips) ✔ Needle Nose Pliers ✔ Seal Pick or O-Ring Removal Tool ✔ Hydraulic Fluid (Mercury or equivalent) ✔ Brake Cleaner or Solvent ✔ Lint-Free Shop Rags ✔ Torque Wrench ✔ Plastic Mallet ✔ Thread Sealant (if needed) Step 1: Safety Precautions 🔴 Ensure the boat is properly secured on a trailer or stand. 🔴 Disconnect the battery to prevent accidental operation. 🔴 Wear gloves and safety glasses to avoid injury. 🔴 Work in a clean, well-ventilated area free from dirt and debris. Step 2: Removing the Trim and Tilt Unit Trim the outboard to its highest position  and secure it using a support bracket or transom saver. Disconnect the hydraulic lines  leading to the trim and tilt system to prevent fluid spills. Use a drain pan to catch excess hydraulic fluid. Remove the mounting bolts  securing the trim and tilt unit to the clamp bracket. You may need to use penetrating oil if bolts are corroded. Carefully lower the unit  and remove it from the bracket. Drain remaining hydraulic fluid  from the system by tilting the unit into a drain pan. Step 3: Disassembling the Trim and Tilt Rams Remove the end caps  from each hydraulic ram using a wrench or spanner tool. Some models require a snap ring removal before the cap can be taken off. Extend the rams manually  by pulling them out of the cylinder. Use compressed air if needed to force them out. Use a seal pick  to carefully remove old O-rings, backup rings, and dust seals. Inspect the ram shafts and cylinders  for wear, pitting, or damage. If the ram is severely corroded, consider replacing it. Step 4: Installing New Seals and O-Rings Clean all components thoroughly  using brake cleaner and a lint-free cloth. Lubricate new O-rings and seals  with hydraulic fluid or silicone grease before installation. Install new O-rings and backup rings  inside the end caps, ensuring they are seated properly. Carefully slide the new seals onto the ram shaft  without twisting or stretching them. Reinstall the end caps  and tighten them securely using a torque wrench (follow manufacturer specs). Step 5: Reassembling the Trim and Tilt System Insert the rams back into the hydraulic cylinder  with a slow, even motion. Reinstall snap rings or retaining rings  to secure the end caps in place. Reconnect the hydraulic lines  ensuring the fittings are tightened securely. Torque all mounting bolts  to the manufacturer’s specifications. Step 6: Refilling and Bleeding the Hydraulic System Refill the hydraulic reservoir  with Mercury or equivalent hydraulic fluid. Cycle the trim and tilt system  multiple times to purge air from the system. Lower and raise the motor fully while checking the fluid level. Check for leaks  around the ram seals and fittings. Top off hydraulic fluid  as necessary. Step 7: Final Checks and Testing Reconnect the battery  and power on the trim and tilt system. Test operation  by trimming the motor up and down multiple times. Ensure smooth movement  without hesitation or leaks. Re-torque any fittings if necessary. Maintenance Tips for Longevity 🔹 Flush the trim system with fresh water  after saltwater use to prevent corrosion.🔹 Check hydraulic fluid levels regularly  and top off as needed.🔹 Inspect for leaks  and worn seals every season.🔹 Lubricate moving parts  to prevent wear and ensure smooth operation. By following these steps, your Mercury Triple Ram Trim and Tilt system  will be restored to full working condition , ensuring smooth operation and reliability  for your outboard motor. 🚤💨

Trigger Firing pairs can you help a faulty trigger quickly! Mercury's 2.0, 2.4, and 2.5-liter 2-stroke V6 outboards use a Capacitor Discharge Ignition (CDI) system that includes a stator, switchboxes, a trigger, ignition coils, spark plug wires, spark plugs, and a voltage rectifier. This guide provides a systematic approach to diagnosing ignition system issues by using a step-by-step deduction process. System Overview Stator : Produces electrical energy for the ignition system. Different stator coils power the port (yellow) and starboard (black) sides of the engine. Switchboxes : Process the trigger signals and direct energy from the stator to the ignition coils, firing the correct cylinders. Trigger : Controls spark timing. It has three coils, each responsible for firing a pair of cylinders (one on the port side and one on the starboard side). Voltage Rectifier : Converts AC voltage from the stator to DC voltage to charge the battery and power onboard electronics. A faulty rectifier can create electrical noise, leading to ignition issues. Ignition Coils : Amplify voltage to create the spark for each spark plug. Spark Plugs and Wires : Deliver the spark to the engine cylinders. Symptoms of Ignition Problems Typical ignition issues include: Misfiring or rough idling. Loss of power in specific cylinders. Engine failure to start or erratic performance. Lack of spark at one or more spark plugs. Overcharging or undercharging of the battery (potential rectifier-related issue). Systematic Diagnostic Steps 1. Preliminary Checks Ensure the battery is fully charged and all electrical connections are tight and corrosion-free. Inspect the voltage rectifier for signs of overheating, melted wires, or bulging. 2. Testing for Spark Remove all spark plugs. Attach a spark tester to each plug wire. Crank the engine and observe for spark at each cylinder. Result Interpretation : No spark on all cylinders : Likely a stator, trigger, or rectifier issue. No spark on one bank (port or starboard) : Likely a stator coil, switchbox, or related wiring issue for that side. No spark on a single cylinder : Likely an issue with the ignition coil, spark plug wire, or spark plug. 3. Deduction Tree for Narrowing Down Issues A. No Spark on All Cylinders Possible Causes : Stator is not producing voltage. Trigger is not sending signals. Faulty voltage rectifier creating electrical interference. Faulty kill switch or wiring short. Tests : Use a multimeter to check stator resistance and output voltage. For Mercury 2.0, 2.4, and 2.5L engines, test the low-speed and high-speed windings against the bench-test specifications on this site. Test the trigger resistance across its three coils. Disconnect the voltage rectifier and retest for spark. A faulty rectifier can cause ignition problems by introducing AC ripple or electrical noise. B. No Spark on One Side (Port or Starboard) Possible Causes : Faulty stator coil dedicated to that side. Faulty switchbox for the affected side. Tests : Check the stator resistance for the specific coil powering the affected side. Compare with specifications. Swap the switchboxes (if identical) and retest for spark. If the problem switches sides, the switchbox is faulty. C. No Spark on One Cylinder Possible Causes : Faulty ignition coil. Faulty spark plug wire or spark plug. Trigger coil not firing that cylinder pair. Tests : Swap the ignition coil with another cylinder. If the problem moves, the coil is faulty. Inspect spark plug wires for breaks or excessive resistance using an ohmmeter. Replace the spark plug and retest. 4. Testing Components A. Stator Disconnect stator leads and measure resistance for port and starboard windings. Test AC voltage output while cranking the engine. Compare results to manufacturer specifications. B. Trigger Test resistance across the trigger’s three coils (e.g., Brown-to-Purple, White-to-Brown, and Purple-to-White). Check for peak voltage signals using a peak-reading adapter on a multimeter. C. Switchboxes Use the “switchbox swap” method to identify faults. Verify proper wiring connections according to Mercury's wiring diagram. D. Voltage Rectifier Use a multimeter to test the rectifier: Test for continuity in the forward and reverse directions (diode test mode). Ensure proper DC voltage output at the rectifier's output terminal. If the rectifier is faulty, disconnect it and retest the ignition system. A faulty rectifier can cause ignition system malfunctions. E. Ignition Coils Measure primary and secondary resistance with a multimeter. Inspect coils for cracks, burns, or physical damage. F. Spark Plug Wires and Spark Plugs Check for physical damage or corrosion. Replace wires if resistance exceeds specifications. Replace spark plugs if fouled or damaged. By systematically testing and isolating components, you can effectively diagnose and resolve ignition problems on your Mercury 2.0, 2.4, or 2.5-liter V6 2-stroke outboard. Including the voltage rectifier in your diagnostic process is essential, as it can indirectly affect the ignition system. Refer to the firing pairs chart  provided to ensure correct wiring and alignment for optimal ignition performance. If issues persist after replacing faulty components, consult a professional marine technician.