MERCURY 5 HP 5MLHA SAIL POWER OUTBOARD MOTOR

Description

The Mercury 5 HP 5MLHA Sail Power outboard motor is a small four stroke built for one job above all: pushing sailboats. It has a 20 inch long shaft, a low pitch high thrust propeller that grips the water on heavy displacement hulls, a built in charging system for your battery, and a proper forward, neutral and reverse gearbox. We have it for sale new, with the Mercury factory warranty, and we ship worldwide.

If you’ve been running a standard small outboard on a sailboat and found it screams at full throttle while the boat barely moves, this is the motor that fixes that. Below I’ll explain why the Sail Power setup matters, what boats it suits, and what you get for your money.

On this page:

• Why a Sail Power outboard
• The high thrust propeller
• Built in charging
• Boats it suits
• On the water
• Features
• Specifications
• Maintenance
• Alternatives
• Price and shipping
• FAQ

Why a Sail Power outboard?

Most small outboards are set up for light, fast boats like inflatables and aluminum skiffs. Their props have enough pitch to push a light hull quickly. Put that same motor on a sailboat, which is heavy for its length and can only move at displacement speed, and the prop can’t do its job properly. The engine revs, but a lot of that effort is wasted.

The Mercury 5 HP 5MLHA Sail Power outboard motor is set up the other way round. Its propeller has a low 6 inch pitch and is designed for thrust rather than top speed. It bites harder at low boat speeds, which is exactly what a sailboat needs to get moving, push into a headwind, and stop or reverse in a marina. Think of it like a low gear on a bicycle for going uphill.

Add the 20 inch long shaft, which keeps the prop in solid water when the stern lifts on a swell, and a built in charging system for your battery, and you’ve got a motor that’s been thought through for sailors rather than adapted from something else.

The model code: 5 horsepower, M manual start, L 20 inch long shaft, H tiller handle, and A for the alternator. “Sail Power” is Mercury’s name for the high thrust sailboat package.

The high thrust propeller

The standard 5 hp comes with an 8 inch pitch prop. The Mercury 5 HP 5MLHA Sail Power outboard motor has a 6 inch pitch high thrust prop. That two inch difference sounds small. On the water it’s the difference between a boat that surges out of its berth and one that wallows while the motor races.

Lower pitch means each turn of the propeller moves the boat a shorter distance, but with more force. On a light skiff, that would cost you top speed. On a sailboat, you were never going to reach high speeds anyway, because the hull has a natural maximum speed based on its waterline length. So you give up nothing useful and gain a lot of push.

You notice it most when:

• Pulling away from a dock or mooring from a standstill
• Motoring into a headwind or chop
• Stopping the boat in reverse as you come alongside
• Holding the bow into wind while you raise sail

Built in charging for your battery

The “A” in 5MLHA stands for alternator. This motor has a charging system rated at 4 amps and 50 watts, supplied with a charging cord. It’s there to keep a small house battery topped up for navigation lights, a VHF radio, a depth sounder or a small instrument. It won’t replace a big charging setup, but on a small sailboat it’s often all you need, especially paired with a small solar panel.

That’s one of the main reasons sailors choose the Mercury 5 HP 5MLHA Sail Power outboard motor over the standard long shaft 5 hp. You get power to the boat’s battery every time you motor, without having to fit an extra kit.

Boats the Mercury 5 HP 5MLHA Sail Power outboard motor suits

Measure from the top of your transom or bracket to the bottom of the hull. Around 20 inches means this long shaft motor. Around 25 inches means extra long, so look at the 5MXLH or the 5MXLHA-LPG Sail Power.

• Day sailers and small keelboats on an outboard bracket
• Trailer sailers, including heavier ones with a cabin
• Small cruising sailboats in sheltered and coastal waters
• Drift boats and small heavy displacement workboats
• Jon boats and utility boats where thrust matters more than speed

For very light, fast boats like inflatables and planing skiffs, the standard pitch prop on the 5MH will usually give you more speed.

On the water with the Mercury 5 HP 5MLHA Sail Power outboard motor

Starting

Open the fuel vent and tap, set the choke when cold, put it in neutral, clip on the lanyard and pull. It usually starts in one or two pulls. Start in gear protection stops it firing up in forward or reverse.

Shifting

Front mounted shift lever with forward, neutral and reverse. In a marina, the combination of reverse gear and the high thrust prop gives you much more control than a standard small motor.

Steering

Lock the motor straight with the steering tension adjustment and steer with the rudder once you’re under way. Free it up when you need the motor to help you turn in tight spaces.

Throttle, noise and exhaust

Twist grip throttle with friction control. Exhaust exits through the prop hub, keeping noise down and fumes underwater and away from the cockpit.

Shallow water drive

Six trim positions plus a shallow water setting that lets you creep into thin water near beaches and moorings with the prop higher.

RPM

Full throttle is 4,500 to 5,500 rpm. With the high thrust prop, the motor should reach that range on a heavy sailboat, where a standard prop might over rev.

Mercury 5 HP 5MLHA Sail Power outboard motor features

• 6 inch pitch high thrust aluminum propeller
• 4 amp, 50 watt charging system with charging cord
• 20 inch long shaft
• Digital CD ignition with spark advance
• High grade marine alloy construction
• Stainless steel water pump housing
• Zinc coated water passages
• Rated for saltwater use
• Sacrificial zinc anodes
• Forward, neutral and reverse gear shift
• Forward mounted gear shift selector
• Adjustable steering tension control
• Twist grip throttle with tension control
• Integrated carry handle
• Thermostat controlled water cooling
• Shallow water drive with 6 trim positions
• Quiet through propeller hub exhaust
• 1.15 litre integral fuel tank
• Start in gear protection
• Low oil pressure warning indicator
• ESG over rev protection
• Safety lanyard stop switch
• Owner’s manual
• Mercury Marine 3 year warranty

Mercury 5 HP 5MLHA Sail Power outboard motor specifications

Mercury’s FourStroke outboards page has the manufacturer’s overview of the range. Ask us if you want a detail confirmed for the unit you’ll receive.

Maintaining the Mercury 5 HP 5MLHA Sail Power outboard motor

Fuel

Sailboat outboards sit a lot, which is hard on small carburetors. Use fresh 87 octane with no more than 10% ethanol, buy it in small amounts, and before any long break turn off the fuel and let the motor run until it stops.

Oil

About 450 ml of 10W-30. Check before each trip. First change at 20 hours, then every 100 hours or yearly.

Gear case

Change the gear lube yearly and look for milky lube.

On the bracket

When sailing, lift the Mercury 5 HP 5MLHA Sail Power outboard motor clear of the water to cut drag and stop marine growth. Rinse with fresh water when you can and check the anodes each season. Keep the charging cord connection clean and dry.

For general safety guidance, the US Coast Guard boating safety site is a useful read wherever you sail.

Buyer questions about the Mercury 5 HP 5MLHA Sail Power outboard motor

“Will it be slower than the standard 5 hp?”

On a light planing boat, yes, a little, because the prop has less pitch. On a sailboat, no. A sailboat’s top speed under power is set by its hull, not the motor, and the Mercury 5 HP 5MLHA Sail Power outboard motor gets you to that hull speed with less strain and more control. On a heavy boat, it often feels faster, because the standard prop would slip and over rev.

“Is 5 hp enough for my trailer sailer?”

For most light to mid weight trailer sailers in sheltered waters, yes, and the high thrust prop helps a great deal. For heavier boats or exposed coastal passages, 6 hp or more gives you extra margin. Tell us your boat’s make and length and we’ll give you a straight answer.

“How much will the charging system give me?”

Up to about 4 amps at higher rpm, less at low rpm. Over an hour of motoring, that’s a useful top up for a small battery running lights and a radio. It won’t run a fridge or a big autopilot. If you need more, add a small solar panel. Many small boat owners find that combination covers everything.

“Can I use it on a dinghy as well?”

You can if the transom is 20 inches, but the high thrust prop is tuned for heavy, slow boats. On a light inflatable, the standard 5MH will be quicker. If you want one motor to do both jobs, the Sail Power will still work, just not as fast on the dinghy.

“How long does the built in tank last?”

It holds just over a litre. For motoring in and out of harbour, that goes a long way. For longer motoring, carry fresh fuel in an approved can and top up with the engine off and cool.

“What about a propane version?”

Mercury also makes a propane Sail Power, the 5MLHA-LPG. It’s ideal if your boat sits for long periods and you’re tired of stale gasoline, or if you already carry propane for the galley.

Installing the Mercury 5 HP 5MLHA Sail Power outboard motor

Set your bracket to the lowest position. Lift the motor on by the handle, centre it and tighten the clamp screws firmly by hand. Tie a safety line to a strong fitting. Raise and lower the bracket to check clearances with the rudder and pushpit through the full steering and tilt range.

Run the charging cord to your battery, with a fuse close to the battery as the owner’s manual describes. Keep the cable tidy and away from the tiller and sheets.

Check the oil, add fresh fuel, clip on the lanyard, put it in neutral and start. Look for the cooling telltale. For the first couple of hours, vary the throttle rather than holding it wide open.

What owners notice after a season with the Mercury 5 HP 5MLHA Sail Power outboard motor

The comment we hear most is about docking. Owners coming from a standard prop small motor say the difference in reverse is remarkable. With the high thrust prop, a burst of reverse actually stops the boat, rather than just churning the water. For anyone who sails into a tight marina, that’s a big deal.

The second is about headwinds. With a standard small motor on a heavy sailboat, pushing into a stiff breeze can feel like the boat is stuck. The Mercury 5 HP 5MLHA Sail Power outboard motor keeps the boat moving forward with more authority, and the engine sounds less stressed while it does it.

Third is the charging. Owners who used to take their battery home to charge it, or fit a separate charging kit, like that it just happens now. Motor out of the harbour, motor back in, and the battery gets a top up both ways.

The honest downside some mention is weight. At around 58 pounds, lifting it single handed over a high stern rail isn’t everyone’s idea of fun. Some owners fit a small lifting tackle to make it easy.

Getting the best from the Mercury 5 HP 5MLHA Sail Power outboard motor

Set the bracket height carefully. The anti ventilation plate should be a few inches under the water with the boat at rest and loaded. Too high and the prop will race in a swell; too low and you add drag.

Trim it upright. Use the tilt pin to get the motor running as vertical as possible. That gives the most efficient thrust.

Don’t run it flat out. A sailboat can’t go faster than its hull speed. Once you’re there, more throttle just burns fuel. Find the point where the boat stops speeding up and back off a touch.

Wear the kill cord. On a sailboat you move about a lot. The lanyard stops the motor if you go over the side or fall.

Lift it when sailing. A motor left in the water adds drag and collects weed and barnacles. Lift the bracket or tilt the motor up once the sails are drawing.

Off season storage

Flush the cooling system with fresh water. Turn off the fuel and run the carb dry. Drain the tank. Change the oil and gear lube. Grease the swivel and clamp screws. Store the Mercury 5 HP 5MLHA Sail Power outboard motor upright or on the correct side in a dry place. In spring, fresh fuel, an oil check and it’s ready.

Who the Mercury 5 HP 5MLHA Sail Power outboard motor is really for

If you own a small keelboat, a day sailer or a trailer sailer, you’re the person this motor was designed around. The Mercury 5 HP 5MLHA Sail Power outboard motor gives you the thrust to handle a heavy hull, the shaft length to keep the prop in the water, and the charging to keep your battery healthy. It’s all in one package, straight out of the box.

It also works well for drift boats, heavy jon boats and small workboats where pulling power matters more than speed. Some river guides and fishermen use them for exactly that reason.

Where it isn’t the best choice is on light, fast boats. On an inflatable or an aluminum skiff that could plane, the lower pitch prop holds you back. For those, the standard 5MH or a bigger motor makes more sense.

If you’re torn between this and another model, send us a note with your boat’s make, length and how you use it. We’ll give you a straight recommendation, even if that means pointing you to a cheaper motor. The Mercury 5 HP 5MLHA Sail Power outboard motor is a great motor on the right boat, and we want it on the right boat.

Spares to keep aboard

A spare spark plug and spanner, a shear pin or prop hardware, a spare lanyard, a small bottle of engine oil, and a spare fuse for the charging circuit. Keep them in a dry bag in a cockpit locker and check them each spring.

Alternatives to the Mercury 5 HP 5MLHA Sail Power outboard motor

5MLHA-LPG Sail Power: the same sailboat setup but running on propane. No stale fuel, ideal for boats that sit.

4MLH: long shaft, standard prop, no built in charging. Fine for lighter sailboats.

6MLH: more power for bigger boats or exposed waters.

5MXLH: 25 inch extra long shaft for tall transoms.

See everything in our Mercury outboard motors category and the 6 HP section.

Mercury 5 HP 5MLHA Sail Power outboard motor for sale: price and worldwide shipping

The price of the Mercury 5 HP 5MLHA Sail Power outboard motor is shown at the top of this page. Add it to your cart, or contact us for a delivered quote.

In the box

• Mercury 5 HP 5MLHA Sail Power outboard motor, new
• 6 inch pitch high thrust propeller, fitted
• Built in fuel tank
• Charging cord
• Owner’s manual
• Mercury Marine 3 year factory warranty from the date of purchase

Shipping

We ship worldwide by courier or freight, securely packed, dry and tracked. Import duty and taxes vary by country, and we’ll explain them before you pay.

Buying from us

Read our refund and return policy, check our customer reviews, and learn more on the about page.

Mercury 5 HP 5MLHA Sail Power outboard motor FAQ

What makes it a Sail Power model?

A 6 inch pitch high thrust prop and a built in charging system, on a 20 inch long shaft.

Does it charge my battery?

Yes, up to 4 amps / 50 watts, with a charging cord supplied.

Does it have reverse?

Yes, forward, neutral and reverse.

How heavy is it?

About 58 pounds.

Is it new?

Yes, new with the full Mercury factory warranty.

Do you ship worldwide?

Yes. Contact us for a delivered price.

Order your Mercury 5 HP 5MLHA Sail Power outboard motor

More thrust where a sailboat needs it, a long shaft, reverse gear and battery charging, all in a motor you can lift by hand. The Mercury 5 HP 5MLHA Sail Power outboard motor is one of the best small auxiliaries for sailboats you can buy. Add it to your cart, or ask us a question. You can also browse all our outboard motors for sale.