SE116 COUNTER ROTATING LOWER (Replaces Mercruiser Gen II)
Introduction
When it comes to reliability, efficiency, and superior performance in marine propulsion systems, the SE116 COUNTER ROTATING LOWER (Replaces Mercruiser Gen II) is a game-changer. Built to withstand harsh marine environments and demanding use, this unit offers unmatched value and performance for boaters seeking a counter-rotating replacement for the Mercruiser Alpha One Gen II lower unit. Whether you’re upgrading or replacing a worn-out drive, the SE116 Lower Unit brings a smooth shift, reliable water pickup, and a solid, corrosion-resistant build.
In this comprehensive guide, we’ll dive into the features, benefits, maintenance tips, troubleshooting steps, and expert advice for making the most of your SE116 COUNTER ROTATING LOWER for marine engines. Learn everything you need to know to keep your boat moving smoothly and efficiently on the water.
Overview / What Is SE116 Counter Rotating Lower?
The SE116 COUNTER ROTATING LOWER is a complete aftermarket replacement for the Mercruiser Alpha One Gen II counter-rotating lower unit. Designed with durability and performance in mind, this unit is ideal for dual-engine setups requiring opposite rotation for proper tracking and steering stability. Counter-rotation units are crucial for twin-outdrive configurations, where one unit must spin in reverse to eliminate torque steer.
This SE116 model comes fully assembled with water pump, shift shaft, drive shaft, and internal gears. It’s ready to install and compatible with the upper units of the Mercruiser Gen II drive. The 100% new construction—not remanufactured—ensures long life and dependable operation. Made with marine-grade aluminum and precision-machined components, it’s built to perform under heavy-duty marine conditions.
Key Features and Benefits of SE116 Counter Rotating Lower
The SE116 offers more than just a replacement—it enhances your boating experience with consistent performance and longevity. Here are some standout features:
- Counter-Rotating Design: Perfect for twin-engine setups to eliminate torque steer and improve handling.
- All-New Construction: Not rebuilt or refurbished—ensures optimal performance from day one.
- Fully Assembled: Includes shift shaft, drive shaft, and water pump pre-installed—ready to bolt on.
- Corrosion Resistant: Marine-grade materials protect against saltwater corrosion.
- Affordable: Offers OEM performance at a fraction of the cost of a new Mercruiser unit.
Whether you’re planning offshore fishing, cruising, or watersports, this unit delivers the torque and reliability you need.
How to Install SE116 Counter Rotating Lower Unit
Installing the SE116 is straightforward if you’re comfortable with mechanical work. Here’s a basic overview:
- Place the boat on a trailer and remove the old lower unit after draining gear oil.
- Align the shift shaft and driveshaft properly with the upper unit.
- Bolt the SE116 Lower Unit in place, following torque specs provided.
- Fill with high-quality marine gear oil and test for leaks.
- Check propeller clearance and reattach if necessary.
Note: Always refer to the SE116 installation manual or consult a certified marine technician to avoid errors.
Maintenance Tips
To keep your SE116 COUNTER ROTATING LOWER performing at its best, routine maintenance is essential. Here are some practical tips:
- Change Gear Oil: After every 100 hours of use or at the end of each season.
- Inspect Seals: Regularly check for water intrusion or oil leaks around the prop shaft.
- Grease Fittings: Lubricate splines and couplings with marine grease.
- Propeller Check: Remove and inspect the prop for fishing line or debris.
- Flush After Use: Especially in saltwater—rinse thoroughly with fresh water.
Routine upkeep ensures extended service life, optimal performance, and minimal downtime on the water.
Common SE116 Counter Rotating Lower Troubleshooting
Despite its high build quality, issues can arise. Here’s how to tackle them:
Shifting Issues
If the unit struggles to shift into gear:
- Check linkage adjustment and alignment
- Inspect the shift cable and tension
- Ensure the shift shaft isn’t bent or jammed
Overheating
Overheating typically stems from water pump issues or blocked inlets:
- Inspect the impeller for wear
- Clear intake screens of debris
- Check water flow output from exhaust port
Expert Advice and Pro Recommendations
Marine experts agree that the SE116 COUNTER ROTATING LOWER provides a cost-effective and reliable solution for dual-drive boats. Compared to OEM units, it delivers similar performance with better affordability. Its all-new internal components reduce failure rates compared to rebuilt parts, and it pairs well with standard Alpha One Gen II uppers.
Buy now and upgrade your marine engine performance with SE116 COUNTER ROTATING LOWER (Replaces Mercruiser Gen II). Use code WELCOME5 to receive 5% off your first purchase!
SE116 Lower Unit Cost and Durability
The cost of replacing a Mercruiser Gen II lower unit with an SE116 is significantly lower than buying a new OEM drive. The SE116 comes with a full one-year warranty and is tested for extreme marine conditions.
Durability is one of its strongest features. With proper care, it easily lasts 5–10 seasons depending on use. Made from precision-machined parts, the unit handles high-RPM operations, long idle sessions, and aggressive acceleration with ease.
Detailed FAQ Section
What makes the SE116 Counter Rotating Lower different from a standard lower unit?
The key difference lies in the direction of rotation. While standard units rotate clockwise (right-hand), counter-rotating lowers spin counterclockwise (left-hand). This is crucial for twin-outdrive configurations where one drive needs to rotate in the opposite direction to balance torque. The SE116 is built for this exact purpose and provides smoother handling and safer maneuverability in dual engine setups.
Additionally, the SE116 COUNTER ROTATING LOWER comes preassembled, built from new components, and designed to replace Mercruiser Gen II lower units with high precision.
Is SE116 compatible with my current upper unit?
The SE116 is compatible with Mercruiser Alpha One Gen II upper units manufactured after 1991. It fits directly with no modification required if your engine setup originally used a Gen II outdrive. Make sure your current unit is a counter-rotating model, as SE116 is not designed for standard rotation replacements.
If in doubt, consult your marine technician or reach out to allboatsupplies.com for compatibility support.
Can I install the SE116 Lower Unit myself?
If you have mechanical experience and proper tools, installing the SE116 yourself is possible. The unit comes fully assembled, which simplifies installation. However, correct alignment of the shift shaft and torque settings is critical. Many boaters choose professional installation to avoid alignment and sealing issues.
Improper installation can lead to leaks or performance issues, so we recommend having a marine tech handle it if you’re unsure.
How do I maintain my SE116 unit for longevity?
Routine maintenance includes gear oil changes, propeller inspections, and flushing after saltwater use. Here’s a quick checklist:
- Change oil every 100 hours or annually
- Inspect for leaks every few outings
- Flush cooling system after each saltwater use
- Lubricate prop shaft splines and couplings
Following this regimen ensures long service life and reduces costly repairs.
What is the warranty for SE116 Counter Rotating Lower?
All SE116 units sold through allboatsupplies.com come with a one-year manufacturer warranty against defects in materials and workmanship. The warranty covers factory-installed parts but does not include damage from improper installation or misuse.
You can also get extended warranty options and live support for setup, installation, and troubleshooting.
Conclusion
The SE116 COUNTER ROTATING LOWER (Replaces Mercruiser Gen II) is a robust, cost-effective solution for boaters requiring precision, performance, and durability. Whether you’re upgrading or replacing, this lower unit delivers reliability and peace of mind on the water. With full compatibility for Gen II uppers and built from all-new parts, it’s one of the best marine engine investments you can make today.
Order now and enhance your twin-drive marine setup with seamless operation and proven performance.
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