Mercury 115 HP Electric Start Steering Trim Tilt CT Long Shaft Outboard Engine

The Mercury FourStroke 115 ELPT EFI CT is a 4-stroke outboard marine engine designed for medium-sized fiberglass, aluminum, or inflatable boats requiring a long shaft, and boats 4–7 meters in length, featuring a 115 HP / 86 kW and 2064 cc 4-cylinder engine. Thanks to its Command Thrust (CT) gearbox system, it has the large gearcase and gearbox of a higher-horsepower engine. The FourStroke 115 ELPT EFI CT, with its 2064 cc 4-cylinder EFI FourStroke engine, offers efficient and reliable power to medium-sized boat users. This model, part of Mercury's most popular power range, stands out with its extensive service network and long-life advantages.

FourStroke 115 ELPT EFI CT Series Features and Technology Advantages

The 4-cylinder design provides balanced vibration and strong torque, ensuring stable cruising in medium-sized boats. EFI electronic injection offers reliable starting in all weather conditions and optimized fuel consumption.

• 4-Cylinder Engine (2064 cc): The 4-cylinder design provides balanced vibration and strong torque, ensuring stable cruising in medium-sized boats
• Long Shaft (508 mm (20")): The propeller operates at the optimum depth at the correct transom height
• EFI Electronic Injection: Easy cold starting and lower fuel consumption compared to carbureted alternatives
• Command Thrust (CT) Gearcase: The large gearcase and gearbox of a higher-horsepower engine — high torque at low RPM and strong thrust capability
• Electric Start: Instant activation with key or button — comfortable and quick starting
• Electric Trim and Tilt (Power Trim & Tilt): Adjust trim angle with a button while cruising — fuel efficiency optimization; tilt to raise the engine completely
• Floating External Fuel System: Connection for a large capacity external tank — range determined by user needs

Long Shaft — Which Boat Type is it Suitable For?

A long shaft (508 mm (20")) is suitable for the vast majority of inflatable, aluminum, and fiberglass boat models. For boats with a transom height of 381 mm, a short shaft model should be preferred.

Technical Specifications

Who is This Engine For?

• Primary engine for 4–7 meter medium-sized boats: 4-cylinder balanced power and quiet operation
• Fishing and coastal cruising: Comfort for long routes with EFI economy
• Family boat and weekly use: Reliable and low-maintenance power source
• Rental boat applications: Extensive Mercury service network and spare part access

Maintenance and Longevity

4-stroke Mercury engines operate trouble-free for many years with regular oil changes and end-of-season maintenance protocols. The impeller of the water-cooled system should be checked every 100 hours or every two seasons. In saltwater use, freshwater flushing is mandatory after every use.

Related maintenance categories: Maintenance Kit | Engine Oil | Impeller | Mercury Spare Parts

Frequently Asked Questions

What boat size is the Mercury FourStroke 115 HP engine suitable for?

115 HP power can fit different sizes depending on the boat's weight and type. General rule: 15–20 kg of boat weight per HP. Always check the maximum engine power recommended by the boat manufacturer.

What advantage does the EFI system offer over a carbureted engine?

EFI (Electronic Fuel Injection) does not require a primer pump or choke adjustment. It provides reliable starting in cold weather and at high altitudes, consistent power output, and lower fuel consumption compared to carbureted alternatives.

What are the maintenance intervals for the Mercury FourStroke?

Oil change at the first 20 hours, then every 100 hours or once a season. Impeller check every two seasons. Freshwater flushing is mandatory after every use in saltwater. End-of-season fuel system protection is recommended.

Which boat and inflatable boat brands are compatible with the FourStroke 115 ELPT EFI CT?

Mercury outboard motors are compatible with many fiberglass, aluminum, and inflatable boat models thanks to their universal transom clamp or transom mounting system. The only criteria are your boat's 508 mm (20") transom height and the maximum engine power approved by the manufacturer. You can get compatibility confirmation from Clever Marin by sharing your boat model.

Related Products and Categories

• Mercury Outboard Motors
• Mercury Marine Products
• Mercury Spare Parts
• Mercury 40–60 HP FourStroke
• Mercury 75–150 HP FourStroke
• Outboard Motors
• Boat Engines
• Maintenance Kit
• Impeller
• Anode

Is This the Right Configuration for Your Boat?

Share your boat model, transom height, and intended use — let's verify together if the Mercury FourStroke 115 ELPT EFI CT engine is suitable for your boat and ensure the correct shaft selection.