Mercury 25MLH 25HP – Four Stroke Manual Start Tiller 20-Inch

Mercury 25MLH 25HP EFI Tiller

The Mercury 25MLH is an advanced 25HP FourStroke outboard engineered for lightweight portability and direct manual tiller control on high-transom vessels in the US maritime market. Boasting a 500cc inline 3-cylinder SOHC engine architecture and a dry weight of 132 lbs, it provides an power-to-weight ratio for transom mounting. This 20-inch long shaft model is perfectly configured for high-transom sailboats, aluminum fishing skiffs, and utility boats. Our dependable marine outboard engines deliver the mechanical reliability and EFI efficiency needed for peaceful navigation in deep coastal estuaries.

Operational peak performance for this Mercury 25HP is achieved across the 5000 to 6000 RPM range. The 2.17:1 gear ratio provides a distinct mechanical advantage, translating the 500cc torque curve directly into steady hull planing and superior trolling capability. Manufactured in the USA, this corrosion-resistant motor features advanced Digital Inductive ignition and battery-free EFI to helps support a quiet, comfortable ride during long days on the water.

Technical Specifications of Mercury 25MLH

- The new 500cc inline three-cylinder SOHC design delivers consistent, vibration-free torque and rapid acceleration under load.
- Advanced Electronic Fuel Injection (EFI) helps support zero-choke starting and incredibly easy maintenance without carburetor jets to clog.
- The ergonomic manual tiller handle provides direct steering control and precise throttle adjustments in one hand.
- Manual pull-start mechanism paired with battery-free EFI helps support reliable ignition without the need for a heavy marine battery.
- Manual tilt with 6 positions allows the operator to easily adjust the engine angle for optimal shallow water navigation.
- An integrated 17 Amp alternator provides charging capability to power essential marine navigation electronics and lights.

SOHC 3-Cylinder Torque

The 500cc 3-cylinder design maximizes combustion efficiency while minimizing the vibration typically found in portable outboards. This results in a smooth torque curve that US mariners depend on when navigating narrow channels or maintaining a steady cruising speed in rough coastal harbors and tidal flows.

Battery-Free EFI Induction

Mercury’s advanced EFI system operates completely battery-free on this manual start model. It continuously monitors atmospheric variables to deliver the appropriate air-fuel ratio, guaranteeing instant one-pull starts and preventing engine bogging during rapid acceleration scenarios, completely eliminating carburetor maintenance.

20-Inch Long Shaft Auxiliary

The 20-inch shaft length is purposefully designed for high-transom vessels and sailboat auxiliary brackets. Its hydrodynamic profile minimizes drag while ensuring the propeller stays efficiently submerged for consistent forward thrust, preventing cavitation in rolling ocean swells.

Mercury Factory Warranty

Every portable Mercury 25HP unit is backed by a comprehensive 3-Year Limited Warranty for American owners. This factory-level protection helps support long-term peace of mind and grants access to genuine parts through a vast nationwide marine dealer service network.

High-Transom Skiff Match

This 20-inch tiller outboard is the ideal match for high-transom aluminum fishing boats, utility skiffs, and as a kicker for larger vessels. It provides the sustained high-end thrust needed for navigating difficult coastal inlets while offering portable convenience.

Maintenance & Longevity

Routine maintenance of the 1.8L oil capacity in the wet sump is vital for maintaining internal mechanical tolerances. Always flush the cooling system with fresh water after each salt-water mission to maintain the engine’s corrosion-resistant properties.Maintenance note: Follow the manufacturer’s service procedures and lubrication specifications for the engine and gearcase.