MERCURY 25 HP EFI 25ELH OUTBOARD MOTOR

Description

The Mercury 25 HP EFI 25ELH outboard motor is a three cylinder, fuel injected 25 hp with electric start, a 20 inch long shaft, tiller steering and manual tilt. It pairs a 526 cc powerhead with a 15 amp, 186 watt charging system, weighs about 171 pounds and suits long shaft aluminum tiller boats, jon boats, utility boats and small fish and ski boats. We have it for sale new with the Mercury factory warranty and ship worldwide.

It’s one of the most popular tiller motors in its class for good reason: smooth, strong, economical and easy to start every time.

On this page:

• Why the Mercury 25 HP EFI 25ELH outboard motor
• Boats it suits
• Features
• Specifications
• Maintenance
• Alternatives
• Price and shipping
• FAQ

Why the Mercury 25 HP EFI 25ELH outboard motor

Because it handles the common jobs of a 15 to 17 foot aluminum boat so well. The three cylinder, 526 cc engine delivers smooth power with strong low end torque, so the boat planes cleanly with a load and cruises at relaxed revs. Fuel injection gives consistent starting and crisp throttle response. Electric start makes it effortless, and the 15 amp charging keeps up with fish finders, livewells and lights.

The long shaft suits most jon boats, tiller skiffs and utility boats with a 20 inch transom, and it makes the Mercury 25 HP EFI 25ELH outboard motor a good candidate for kicker duty on larger boats too.

Model code: 25 hp, E electric start, L 20 inch long shaft, H tiller, EFI fuel injection.

Boats the Mercury 25 HP EFI 25ELH outboard motor suits

Measure from the top of your transom to the bottom of the hull. About 20 inches means this long shaft. About 15 inches means the 25EH. Check your capacity plate.

• Aluminum tiller boats of 15 to 17 feet
• Long shaft jon boats
• Utility and work boats
• Small fish and ski boats
• Small pontoons where rated

On the water

Clip on the lanyard, put it in neutral and press start. It settles into a smooth idle and responds crisply. Shift and steer from the tiller, and the boat planes cleanly. Full throttle is 5,000 to 6,000 rpm.

Real world setups

A 16 foot tiller fishing boat with electronics and two anglers is the classic match. The Mercury 25 HP EFI 25ELH outboard motor planes it with a load, trolls smoothly and keeps the battery charged. On a long shaft jon boat on a river, it has the torque to handle current and the reliability of push button starting on cold mornings. On a small pontoon, it gives a pleasant cruise.

Buyer questions

“Manual tilt or power trim?”

This model has manual tilt. For power trim and tilt, choose the 25ELHPT.

“Is a battery included?”

No. You’ll need a suitable marine battery.

Mercury 25 HP EFI 25ELH outboard motor features

• Three cylinder, 526 cc four stroke
• Electronic fuel injection
• Electric start
• 15 amp, 186 watt charging system
• 20 inch long shaft
• Smooth running with superior balance
• Great low end torque for planing
• Tiller steering with forward, neutral and reverse
• Water cooled with thermostat
• Mercury Marine factory warranty

Mercury 25 HP EFI 25ELH outboard motor specifications

For the manufacturer’s own overview of the range, see Mercury’s FourStroke outboards page. Mercury updates details between model years, so if one spec really matters to your purchase, ask us and we’ll confirm it on the exact unit we ship.

Maintaining the Mercury 25 HP EFI 25ELH outboard motor

Fuel: fresh 87 octane, up to 10% ethanol.

Oil: Mercury four stroke oil; check before each trip and change on schedule.

Gear case: change the lube yearly.

Battery: clean terminals; keep charged over winter.

Cooling: check the telltale every start; flush after saltwater use.

If you’re newer to boating, the US Coast Guard boating safety site is worth a read. It’s written for US boaters, but the advice on kill cords, life jackets, fuel handling and navigation rules applies wherever you are in the world.

Why three cylinders make a difference

Most outboards in the 15 to 20 hp class use two cylinders. Mercury’s 25 and 30 hp EFI motors, including the Mercury 25 HP EFI 25ELH outboard motor, use three. That matters more than you might think. With three cylinders, the power pulses overlap more evenly, so the engine runs noticeably smoother, with less vibration through the tiller and transom. It also idles more steadily, which you appreciate when trolling or creeping through a no wake zone.

The 526 cc displacement gives strong low end torque, so the boat gets up on the plane briskly without having to rev the engine hard. And because the engine isn’t working as hard at cruise, it tends to be quieter and more economical than a smaller engine pushed to its limit.

What electronic fuel injection means for you

The Mercury 25 HP EFI 25ELH outboard motor uses electronic fuel injection, or EFI, instead of a carburetor. In plain terms, a small computer measures things like air temperature and engine load and injects exactly the right amount of fuel every time. You don’t need to fiddle with a choke. It starts easily whether it’s a frosty morning or a hot afternoon, it idles smoothly, and it responds cleanly when you open the throttle.

EFI is also less fussy about sitting. Carburetors have tiny jets and a fuel bowl that gum up when old fuel evaporates inside them. A sealed injection system is much more tolerant, although fresh fuel is still the best policy. And because the fuel is metered precisely, EFI motors tend to be more economical, which means more time on the water per tank.

Mercury’s small EFI engines can even start and run without a battery on manual start models: the pull of the cord generates enough power for the fuel injection system to fire. That’s a clever bit of engineering, and it means you get the benefits of EFI without having to carry a battery if you don’t want to.

Getting the propeller right

The propeller is the part of your Mercury 25 HP EFI 25ELH outboard motor that actually turns engine power into movement, and the right one makes a big difference. The goal is simple: with your boat loaded the way you normally use it, the engine should reach the top of its recommended full throttle rpm range. If it can’t get there, the prop pitch is too high and the engine is labouring. If it goes past the top of the range, the pitch is too low and the engine is over revving.

As a rough guide, each inch of pitch changes full throttle rpm by around 150 to 200 rpm. Heavier loads and bigger boats usually want less pitch. Lighter, faster boats can take more. If you mainly carry heavy loads or tow, a lower pitch prop helps. If you run light and want top speed, a higher pitch may suit. Tell us about your boat and how you use it, and we’ll help you choose.

Trailering with your motor

Most owners of a motor like the Mercury 25 HP EFI 25ELH outboard motor leave it on the boat and trailer them together. A few habits protect the motor on the road. Use a transom saver or motor support bracket where recommended, so the motor isn’t bouncing on its tilt mechanism over bumps. Make sure there’s good ground clearance under the skeg. Close the fuel vent and disconnect the fuel line. And check the motor mounting bolts or clamps before every trip, because vibration on the road can loosen them over time.

At the ramp, lower the motor only once there’s enough water under it, and raise it before you drive the boat onto the trailer. It sounds obvious, but a surprising number of skegs and props get damaged at the ramp rather than out on the water.

Kicker motor basics

A kicker is a small outboard mounted beside a boat’s main engine, mainly for trolling. Big engines are built to run fast, and many can’t idle down slowly enough for trolling. Running them at idle for hours also isn’t kind to them. A kicker like the Mercury 25 HP EFI 25ELH outboard motor trolls all day at a steady low speed, burns a fraction of the fuel and saves hours on the main engine.

It also doubles as a get home motor. If the main engine fails, a kicker will bring a mid size fishing boat back to the ramp slowly but surely. For anglers who fish big lakes or open water, that backup alone is reason enough to fit one.

Most kickers are mounted on a dedicated kicker bracket, which lifts the motor clear of the water when you’re running on the main engine. A connector bar can link the kicker’s steering to the main engine, so you steer from the helm while trolling.

Using your motor through the seasons

In spring, check the oil, fit fresh fuel, look over the fuel line and connectors for cracks, and run the engine on a flushing attachment or in a test tank before the first real trip. Look for a strong cooling stream and a smooth idle.

Through summer, the main jobs are fresh fuel, regular oil checks and rinsing after saltwater use. Keep an eye on the propeller for dings. A damaged prop costs you speed and fuel, and can cause vibration.

In autumn, before the boat is laid up, do the full storage routine: flush, change the oil and gear lube, deal with the fuel system as the owner’s manual describes, grease the moving parts and store the Mercury 25 HP EFI 25ELH outboard motor somewhere dry. Twenty minutes in autumn saves hours of frustration in spring.

Paperwork, warranty and keeping records

When your Mercury 25 HP EFI 25ELH 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.

Why buy from us

We deal in outboard motors every day, and we would rather give you a straight answer than make a quick sale. If you are not sure the Mercury 25 HP EFI 25ELH outboard motor is the right motor for your boat, message us with the make, model and length of the boat, how you use it and where you boat. We will tell you honestly whether it is a good match or whether something else would suit you better.

Every motor is packed carefully for the journey, and we keep you updated from dispatch to delivery with tracking. We ship worldwide, and we are happy to explain in advance what to expect with import duties and local taxes in your country, so there are no surprises when it arrives.

After you buy, we are still here. If you have questions about setup, break in or maintenance, just ask.

A small spares kit worth carrying

You do not need a workshop on board, but a few cheap parts turn most breakdowns into a ten minute fix. For the Mercury 25 HP EFI 25ELH outboard motor, we suggest a spare spark plug and the right spanner, spare propeller hardware, a spare kill cord, a small bottle of engine oil, a couple of fuses if the motor has electrics, and a fuel line O ring or connector seal. Add some cable ties, a roll of self amalgamating tape and a basic multi tool.

Pack it all in a small dry bag, keep it in the boat, and check it every spring. Most owners never need it. The ones who do are very glad it was there.

A quick checklist before every trip

It sounds obvious, but most days that go wrong on the water start with something small that got missed at the dock. Before you head out with your Mercury 25 HP EFI 25ELH outboard motor, run through this in your head:

• Enough fresh fuel for the trip, plus a sensible margin
• Engine oil checked and at the right level
• Motor mounted securely and everything tight
• Kill cord clipped to you, not left on the tiller or dash
• Cooling telltale spraying water once the engine is running
• Life jackets, a way to call for help, and a small spares kit aboard

It takes a minute or two. It is also the habit that separates relaxed boat owners from the ones waiting for a tow.

More questions we get asked

Can I install the Mercury 25 HP EFI 25ELH outboard motor myself?

Many owners do, following the owner’s manual. If you are not confident with mounting, rigging or electrics, a local marine mechanic can set it up quickly, and it is money well spent.

How often does it need servicing?

Check the oil before every trip. Change the engine oil and gear lube at least once a year, or at the hour intervals in the owner’s manual, whichever comes first. Inspect the water pump impeller regularly and replace it as recommended.

What fuel should I use?

Fresh unleaded petrol of the octane rating shown in the specifications, with no more than 10% ethanol, unless it is a propane model. Old fuel is the cause of most running problems.

Can I pay in instalments?

Payment options vary by country. Contact us and we will tell you what is available for your order.

Why fuel care matters so much

If there’s one thing that decides whether an outboard starts first time or leaves you pulling and swearing at the ramp, it’s fuel. Modern petrol, especially with ethanol blended in, starts to break down within weeks. It absorbs moisture, separates and leaves gummy deposits that block the tiny passages in fuel systems.

For your Mercury 25 HP EFI 25ELH outboard motor, the rules are simple. Buy fresh fuel from a busy station. Don’t store it for months in a can. Keep the tank vent closed when the boat isn’t in use. Use a fuel stabiliser if the boat will sit for more than a few weeks. And before any long lay up, deal with the fuel system as the owner’s manual describes, rather than leaving old fuel inside the engine. It’s a few minutes of effort that saves a lot of cost and frustration.

Alternatives to the Mercury 25 HP EFI 25ELH outboard motor

25MLH EFI: manual start, no battery needed.

25ELHPT EFI: adds power trim and tilt.

20ELH EFI: lighter two cylinder option.

25ELHGA Jet: jet drive for shallow rivers.

See our main Mercury outboard motors category.

Mercury 25 HP EFI 25ELH outboard motor for sale: price and worldwide shipping

The current price of the Mercury 25 HP EFI 25ELH outboard motor is shown at the top of this page. You can add it to your cart and check out straight away, or if you’d rather talk to a person first, send us a message through our contact page and we’ll come back to you with a full delivered price to your country.

What you get

• Mercury 25 HP EFI 25ELH outboard motor, new
• Owner's manual
• Mercury Marine 3 year factory warranty from the date of purchase

Propeller, fuel tank and battery can be supplied on request to suit your boat.

Shipping worldwide

We ship to buyers all over the world. Every motor is packed securely for the journey and sent by courier, freight or sea depending on its size and where you are, with tracking from dispatch to delivery. Import duty and local taxes depend on your country, and we’re happy to explain what to expect before you pay so there are no surprises.

Buying with confidence

Have a read of our refund and return policy, see what other boat owners have said on our customer reviews page, and find out more about who we are on the about page.

Mercury 25 HP EFI 25ELH outboard motor FAQ

What shaft length is the Mercury 25 HP EFI 25ELH outboard motor?

20 inches, long shaft.

How much does it charge?

Up to 15 amps.

How heavy is it?

About 171 pounds.

Do you ship worldwide?

Yes. Contact us for a delivered quote.

Order your Mercury 25 HP EFI 25ELH outboard motor

Smooth three cylinder power, long shaft, electric start and strong charging. Add the Mercury 25 HP EFI 25ELH outboard motor to your cart now, or send us a question first. You can also compare it with the rest of our outboard motors for sale.