2018 Mercury 9.9 Hp 9.9EXLH-CT Outboard Motor

Mercury's 9.9EXLH-CT from 2018 brings a 25-inch extra-long shaft together with electric start and the CommandThrust lower unit, intended for transoms that sit higher than the standard mount, like many sailboats and taller pontoons carry on their stern.

Match the shaft to the transom

An extra-long shaft keeps the gearcase and prop at the right depth on a tall transom; mounted on a shallower one, that same length drives the propeller too far down into the water column. Confirm transom height before buying rather than guessing from the boat type alone, since getting this wrong hurts performance more than horsepower ever would.

What the CommandThrust lower unit is tuned for

A 2.42:1 ratio spins a larger four-blade propeller, built for push rather than top speed, favoring low-speed thrust over quick acceleration, which suits a wider or heavier boat that needs help getting on plane. Tilt uses Mercury's ratcheting manual system rather than an electric motor, which keeps the unit lighter and simpler to service over time.

Running it

Steering rides on the tiller handle along with the throttle twist and shift lever, and the whole unit is built to withstand saltwater exposure for coastal owners.

Common questions

Does this start with a key or a cord? Electric start is standard on this motor.

Does the propeller come installed? Yes, the CommandThrust four-blade aluminum propeller ships on the motor.

Specifications