Mercury 5MLH Propane FourStroke

This used Mercury 5MLH Propane FourStroke is the 20-inch-shaft, tiller-steered version of Mercury's propane 5hp outboard line, started manually and cooled by a water-and-thermostat system typical of small FourStroke engines. It runs on LPG and connects to any propane tank fitted with a standard US POL connector.

What's inside the 5MLH

Mercury lists this single-cylinder engine's displacement at 7.5 cubic inches, or 123 cc, turning a 2.15:1 gearcase and reaching full throttle between 5000 and 6000 rpm. On the scale it comes to 59 lbs dry, among the lightest outboards Mercury sells in this horsepower class. Shift runs forward-neutral-reverse, shallow water trim covers 16 degrees across 6 manual positions, and exhaust routes through the propeller for a quieter note at the dock.

What else to know

Ignition is CDI with electronic spark advance, and Mercury calls for its own FourStroke 10W-30 oil to keep the engine running smoothly. Being previously owned, this unit's exact condition depends on how it was run; reach out for hours or upkeep records ahead of purchase. This engine family carries 3 years of standard coverage from Mercury.

Is a propeller part of the package here? Mercury's own specifications for this engine show a propeller as included.

Can I switch this motor to run on gasoline? No, this model is built specifically for propane fuel, not for gasoline. Mercury outboards