MERCURY 6 HP 6MH OUTBOARD MOTOR

Description

The Mercury 6 HP 6MH outboard motor is the strongest of Mercury’s single cylinder portables. It’s still light enough to carry at about 57 pounds, it has its own built in fuel tank, and it gives you a proper forward, neutral and reverse gearbox. If you’ve got a small jon boat, a skiff or a bigger inflatable and you want the most power you can get before stepping up to a heavier twin, this is it. We have it for sale new, with the Mercury factory warranty, and ship it worldwide.

Below you’ll find what the Mercury 6 HP 6MH outboard motor is good at, which boats suit it, the full specifications, how to look after it, and some straight answers to the questions people ask us before they buy.

On this page:

• Why the Mercury 6 HP 6MH outboard motor
• What 6MH means
• Boats it suits
• On the water
• Features
• Specifications
• Maintenance
• Buyer questions
• Compared with nearby models
• Price and shipping
• FAQ

Why the Mercury 6 HP 6MH outboard motor

There’s a big jump in Mercury’s range between the single cylinder portables and the twin cylinder 8 and 9.9 hp motors. The twins are smoother and stronger, but they weigh around 84 to 95 pounds and need a separate fuel tank. That’s a lot to carry from the car to the dock.

The Mercury 6 HP 6MH outboard motor sits at the top of the lightweight group. It uses the same 123 cc single cylinder as the 4 and 5 hp, tuned to run a little higher in the rev range, with a full throttle band of 5,000 to 6,000 rpm. The result is the most power you can get from a small Mercury that still weighs under 60 pounds and still carries its own fuel.

For a lot of boaters that’s the perfect balance. Enough punch to push a loaded skiff with some authority, light enough to carry by hand, and simple enough to throw in the back of a car without a separate tank and fuel line.

It’s a four stroke, so it runs on straight unleaded, idles smoothly, doesn’t smoke and is easy on fuel. It has a pressurised wet sump oil system with a low oil pressure warning, which is kinder to the engine over long hours than the splash systems used on the smallest motors.

What “6MH” means

• 6 is the horsepower.
• M is manual start, a pull cord.
• H is tiller handle steering.
• No L means a 15 inch short shaft.

If your boat needs a 20 inch long shaft, look at the Mercury 6MLH instead.

Boats the Mercury 6 HP 6MH outboard motor suits

Measure from the top of your transom down to the bottom of the hull. Around 15 inches means this short shaft motor fits. Around 20 inches means you want the long shaft 6MLH.

Boats that suit the Mercury 6 HP 6MH outboard motor:

• Small jon boats with low transoms
• Aluminum skiffs and car toppers around 10 to 12 feet
• Inflatables and RIBs up to about 3.5 or 3.8 metres, within their rating
• Yacht tenders that carry more than one or two people
• Small utility boats and punts on calm water

On a light inflatable, 6 hp will usually get you on the plane with one person and sometimes two. On a 12 foot aluminum skiff, expect a brisk displacement cruise with two aboard, and possibly planing with one light person. For planing a 14 footer with two adults and gear, you’ll want the 8MH or 9.9MH. Always check your boat’s capacity plate before fitting any motor.

Running the Mercury 6 HP 6MH outboard motor

Starting

Open the fuel vent and tap, set the choke when cold, put it in neutral, clip on the lanyard and pull. Start in gear protection stops it starting in forward or reverse. Once warm it usually fires on the first pull.

Shifting

The shift lever is on the front of the motor, within easy reach. Forward, neutral and reverse. Proper reverse makes launching, docking and getting off snags easy.

Throttle and steering

Twist grip throttle with friction control, so you can set a speed and let go. Adjustable steering tension keeps the tiller steady.

Shallow water drive and trim

Six trim positions and a shallow water drive setting that locks the motor partly tilted for creeping over weed beds, sand and rocks.

Noise

Exhaust exits through the prop hub. The motor is quiet at trolling speed and doesn’t leave you smelling of fuel.

Speed

Speed depends on your boat, load and conditions, so I won’t quote a number that won’t match your setup. What matters is that the Mercury 6 HP 6MH outboard motor reaches its 5,000 to 6,000 rpm range comfortably on a suitable boat.

Mercury 6 HP 6MH outboard motor features

• Compact and lightweight, about 57 lb
• 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 with external tank connection
• 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 6 HP 6MH outboard motor specifications

For Mercury’s own overview of the range, see their FourStroke outboards page. Ask us if you need any detail confirmed for your unit.

Maintaining the Mercury 6 HP 6MH outboard motor

Fuel

Fresh 87 octane unleaded, no more than 10% ethanol. Stale fuel is the main reason small motors won’t start. Before any break of more than a few weeks, shut off the fuel and run the Mercury 6 HP 6MH outboard motor until it stops, so the carb bowl is empty.

Oil

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

Gear case

Change the gear lube once a year. Milky lube means water is getting past a seal.

Cooling and saltwater

Check the telltale stream every time you start. After saltwater use, flush with fresh water and keep an eye on the anodes.

Carrying

Carry it upright by the handle. Lay it down only on the side the owner’s manual shows.

The US Coast Guard boating safety site is a useful read on the basics of safe small boating, wherever you are.

Questions buyers ask about the Mercury 6 HP 6MH outboard motor

“Should I buy the 6 or stretch to the 8?”

It comes down to what matters more to you: carrying weight or performance. The 8 hp is a twin cylinder, smoother at speed and stronger, and it’ll plane a bigger boat. But it’s around 27 pounds heavier and needs its own remote fuel tank. If you lift your motor on and off the boat often, or carry it any distance, the 6 is much easier to live with. If it stays on the boat most of the time and you want speed, the 8 makes sense.

“Will it plane my inflatable?”

On most light inflatables in the 3 to 3.5 metre range, with one person aboard, usually yes. With two it depends on the boat, the load and the prop. Check the maximum horsepower on your inflatable’s plate first. Many are rated for 6 hp or more, and this is a popular pairing.

“How far will the built in tank take me?”

The internal tank is a little over a litre. That’s fine for short runs and for tender work, but for a full day of fishing you’ll want to connect an external tank. The connection is already built into the motor, so it’s just a matter of adding a portable tank and fuel line.

“Is it hard to start?”

No. With fresh fuel and the choke set properly, it usually starts in a pull or two. If it doesn’t, check the basics first: fuel tap open, tank vent open, lanyard clipped in, gear in neutral. Nine times out of ten that’s the answer.

“Is it good in saltwater?”

Yes, it’s saltwater rated with zinc anodes and coated water passages. Flush it with fresh water after every salty trip and it’ll last.

Real world setups

The loaded tender

Families on cruising yachts often run a 3 metre inflatable with three or four people and shopping aboard. A 2.5 or 3.5 hp struggles there. A 6 hp, with its reverse gear and extra push, makes the trip ashore far more comfortable and safer in a chop.

The small jon boat

A 10 to 12 foot jon boat on a river or small lake, one or two anglers, a couple of rods. The 6 moves it along nicely and trolls smoothly, and the shallow water drive helps in the skinny water where jon boats are often used.

The car topper

If your boat goes on the roof of the car, every pound counts on the motor too. At 57 pounds with no separate tank, this is about the most capable motor you can realistically carry down a beach or a boat ramp without a trolley.

Setting up your new Mercury 6 HP 6MH outboard motor

When the motor arrives, unpack it and check it over. If anything looks damaged from shipping, tell us straight away. Check the oil on the dipstick and top up to the mark if needed.

Clamp the motor to the centre of the transom and tighten both clamp screws firmly by hand. Tie a safety line from the motor to the boat. Set the tilt pin so the motor sits roughly upright in the water with the boat loaded as you normally use it. You can fine tune it later to get the smoothest ride.

Fill the built in tank with fresh fuel, or connect an external tank. Open the vent and fuel tap. Clip the lanyard to yourself, put it in neutral, set the choke and start it. Let it idle for a minute and check that water is spraying from the cooling telltale.

For the first couple of hours, vary the throttle and don’t hold it at full speed for long. After that, run it normally. Change the oil after the first 20 hours of use.

Getting more range and less fuel use

On any small boat running at displacement speed, the last part of the throttle travel adds very little speed and a lot of fuel use. Ease off from full throttle and you’ll often lose almost nothing in speed while the motor gets quieter and burns noticeably less. On a boat that’s planing, find the lowest throttle setting that keeps it on the plane and hold it there.

For longer outings, an external tank changes everything. A few litres of fresh fuel in a portable tank lets you fish or explore all day without topping up.

Off season storage

Flush the motor with fresh water. Shut off the fuel and run it until it stops. Drain the built in tank. Change the oil and gear lube. Grease the swivel and clamp screws. Store the motor upright on a stand, or on the correct side as shown in the owner’s manual, in a dry place. In spring, fresh fuel and an oil check are all it needs.

Spares worth carrying

A spare spark plug and spanner, a shear pin or prop hardware, a spare lanyard, a small bottle of oil and a spare fuel line O ring if you use an external tank. Keep them in a dry bag in the boat.

Security

Small outboards are easy to steal. If the motor stays on the boat, fit a lock over the clamp screws and record the serial number. When you leave the boat for long periods, take the motor home. At 57 pounds, that’s easy to do.

What owners tell us about the Mercury 6 HP 6MH outboard motor

After a season, the most common comment from owners is that the Mercury 6 HP 6MH outboard motor feels bigger than it is. People who stepped up from a 3.5 or 4 hp are surprised by how much better the boat moves with the same amount of carrying weight, give or take a couple of pounds.

The second comment is about reverse and the front mounted shift. Owners who came from a small motor that had to be spun round for reverse love having a real gearbox, especially when coming alongside a jetty or backing off a beach.

Third is starting. Owners who keep to fresh fuel and run the carb dry before long breaks tell us the Mercury 6 HP 6MH outboard motor starts reliably, often on the first pull.

The honest downside a few mention is the small built in tank. For anything beyond short trips they add an external tank, which fixes it completely.

Four stroke vs the old two stroke

Some buyers are replacing an old 6 hp two stroke. The old motors were lighter by a few pounds and very simple, but they needed oil mixed into every tank of fuel, they smoked, smelled and drank fuel, and in many countries they’re no longer sold new. The Mercury 6 HP 6MH outboard motor runs on straight unleaded, idles smoothly, trolls quietly and uses far less fuel. Most people don’t look back.

Why so many people choose a small Mercury

Mercury’s dealer and parts network is one of the biggest in the world. Wherever you boat, spark plugs, impellers, anodes and props for the small Mercury four strokes are easy to find. That makes the Mercury 6 HP 6MH outboard motor an easy motor to own long term, whether you’re at home or cruising far away.

Paperwork, warranty and keeping records

When your Mercury 6 HP 6MH outboard motor arrives, write down the serial number and keep it with your invoice. Take a photo of the serial plate on your phone too. If you ever need warranty work, a dealer will ask for both, and it makes the process much quicker. The Mercury factory warranty starts from the date of purchase, so hang on to that paperwork.

It is also worth keeping a simple log: date, engine hours if you have them, oil changes, gear lube changes, impeller replacements and anything unusual you noticed. It takes seconds after each service, and it adds real value if you ever sell the boat. Buyers pay more for an engine with a clear service history, and it helps any mechanic you work with understand the motor quickly.

Check your boat insurance as well. Many policies have specific requirements for outboard security, such as a lock on the clamps or bracket, and some ask for the serial number. Better to sort that out on day one than find out after a problem.

The Mercury 6 HP 6MH outboard motor compared with nearby models

Versus the 5MH: very similar size and weight. The 6 runs a bit higher in the rev range for a little more power. Unless a 5 hp limit applies, the 6 gives you more in reserve.

Versus the 8MH: the 8 is a smoother twin cylinder with more power, but it’s around 84 pounds and needs a separate tank. Choose the 6 if portability matters most.

Versus the 4MH: same family and weight class, less power.

See the full range in our Mercury 6 HP outboard motors section and the main Mercury outboard motors category.

Mercury 6 HP 6MH outboard motor for sale: price and worldwide shipping

The price of the Mercury 6 HP 6MH outboard motor is at the top of this page. Add it to your cart, or contact us for a delivered quote to your country.

In the box

• Mercury 6 HP 6MH outboard motor, new
• 3 blade aluminum propeller, fitted
• Built in fuel tank with external tank connection
• 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. We’ll explain import duty and taxes for your country before you pay if you ask.

Buying from us

Read our refund and return policy, see our customer reviews, and visit the about page.

Mercury 6 HP 6MH outboard motor FAQ

Does the Mercury 6 HP 6MH outboard motor have reverse?

Yes, forward, neutral and reverse.

How heavy is it?

About 57 pounds.

Does it need a separate fuel tank?

No, it has a built in tank, plus an external tank connection for longer runs.

Does it charge a battery?

Not as standard. An optional 12V 50W charging coil can be fitted.

Is it new?

Yes, new with the full Mercury factory warranty.

Do you ship worldwide?

Yes. Contact us with your location for a delivered price.

Order your Mercury 6 HP 6MH outboard motor

The most power you can get from a small Mercury that you can still carry by hand. Add the Mercury 6 HP 6MH outboard motor to your cart today, or ask us a question. You can also browse all our outboard motors for sale.