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MERCURY MARINE
2.5hp & 3.5hp 4-Stroke Outboards
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2.5hp & 3.5hp 4 Stroke Outboards
Mercury Marine’s 4-stroke technology consumes 40% less fuel than 2-stroke models for extraordinary value and savings
Engines surpass California Air Resources Board (CARB) 3-Star Rating, making them some of the cleanest running on the market—with 91% less emissions than traditional 2-stroke outboards!The inherent 4-stroke characteristics of ultra-quiet, smoke-free operation, plus smooth idling and running make these engines a natural choice whether you’re trolling for fish or out just for fun. Clean running 4-stroke engines from 2.5 to 20hp have a CARB three-star, ultra-low emissions rating. The decompression system and electronic CD ignition design ensure an easy, reliable start. One-stage over-rev protection and low oil pressure warning system provide extra peace of mind. Exclusive multifunction tiller handle on the 8hp and 9.9hp models features shift, steering, throttle, throttle friction, and stop controls for convenient one-hand operation. Available in manual-tilt, gas-assist and power-trim. All models are sold with a propeller.
- Engine Type: 4-stroke
- Features: 4-stroke technology—quiet, environmentally friendly, 40% more fuel efficient than comparable 2-stroke engines, smooth running/exceptional idling
- Exhaust: Above prop
- Start: Manual, with decompression system
- Steering Type: Tiller (2.5hp–6hp), tiller or remote (8hp and higher)
- Warranty: Three years
- For U.S. shipment ONLY
2.5hp & 3.5hp 4-Stroke Outboards
- Patented one-piece integrated cylinderblock design provides added reliability by eliminating gaskets and fasteners and makes the powerhead much more compact and lightweight
- Check oil level without removing the cowling with convenient, easy-to-view sight gauge
- This engine delivers maximum performance with the largest displacement in the 2.5 hp category
- A twist-grip throttle and 360-degree steering make it easy to use
- Steering Type: Tiller with 360° turning
- Gearing: F-N, 2.15:1
- Trim Positions: 4
- Tank Type: Integral fuel tank (gal / L)
- Tank Capacity: 0.3gal.
Note: These Mercury outboards have 4-stroke engines and, like virtually all 4-stroke engines, depend on oil in their crankcases for lubrication. To prevent the oil from leaking during transport, the engines are not shipped with oil in their crankcases. You must put the correct amount and grade of oil in the crankcase prior to the first use or you will cause extensive damage to your engine, which is not covered by your engine’s warranty. Please read the owner’s manual for more information. For U.S. shipment ONLY. |
REVIEW SNAPSHOT®
by PowerReviews(based on 13 reviews)
Ratings Distribution
38%
of respondents would recommend this to a friend.
Pros
- Compact (5)
- Easy to use (4)
- Easy storage (3)
Cons
- Unreliable (8)
Best Uses
- Boating / sailing (8)
- Reviewer Profile:
- Casual/ recreational (7), Advanced (3), Professional (3)
Reviewed by 13 customers
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Displaying reviews 1-10
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Pros
- Compact Design
- Easy To Use
Cons
- A fuel issue
Best Uses
- Boating
- Sailing
Comments about 2.5hp & 3.5hp 4 Stroke Outboards:
I have a 3.5. I like the motor. There was a carb problem. There are two adjustments on the carb. Throttle and idle. The idle is under a plug you have to remove. The idle on my motor was not adjusted right at the factory it would stall. You have to richen the fuel mixture. Adjusting the throttle screw to keep the motor running will not take care of the problem everyone sayes they are having.
Service and delivery comments:
Everything was fine.
Pros
- Compact Design
- Easy Storage
- Easy To Use
- Safe
- Waterproof
Cons
Best Uses
- DinghyTender
Comments about 2.5hp & 3.5hp 4 Stroke Outboards:
As long as you keep the gas spiked with "Sea Foam" this things runs very well.
If you don't, the tiny carb WILL stick.
Pros
Cons
- Unreliable
Best Uses
- Boating
Comments about 2.5hp & 3.5hp 4 Stroke Outboards:
I bought this motor for my son in 2009. It ran for about 8 hours, then suddenly it would just stop running and refusing to start. I took it to have it fixed twice thinking the warranty would cover me. No dice, the authorized Mercury repair shops said it is a fuel issue and Mercury won't cover it. From my 30 plus years of boating, I know it is not a fuel issue. Mercury refuses to admit there is a design flaw with this motor. Finally, I just gave up and bought a new Honda. Way to go Mercury, after several decades of buying Mercury outboards, you lost a customer. And from the looks of other people who have left their reviews, probably much more. By the way, the Honda is stored and used exactly like the Mercury and I have had zero problems after two seasons of use.
Pros
Cons
- Unreliable
Best Uses
- Boating
Comments about 2.5hp & 3.5hp 4 Stroke Outboards:
This outboard ran fine for the first 10 hours and then suddenly would not start without fully opening the throttle. It also will not idle no matter how long it has been warmed up and dies unexpectedly while running. We have brought it back for repair twice and saw no improvement either time. Both times the service center blamed it on water in the gas even though we empty the tank completely after every use.
It's a real lemon and Mercury refuses to even cover the cost of the repair.
Pros
- Compact Design
Cons
Best Uses
- Boating
Comments about 2.5hp & 3.5hp 4 Stroke Outboards:
I've owned a brand new 3.5 for over a year now. It has been run quite frequently, long & short jaunts, multiple on/offs in a day and has even been dropped onto a hard cement deck. Broke it in per the manual instructions and has kept ticking. The only peeve I have is when I forget to vent the tank before staring...that's my problem. Runs on regular gas with no problems. It is a 2010 model...maybe the kinks have been worked out.
Pros
Cons
- Basic rip off
- Hard to start stalls
- No low idle
- Unreliable
Best Uses
Comments about 2.5hp & 3.5hp 4 Stroke Outboards:
Unreliable engine that changed how and where I anchored while cruising Maine this summer, meaning I had to be close enough in to row inflatable, I wish I had kept my Honda or gone with Yanmar. Mercury will not take it back despite three year warranty.
Pros
Cons
- Unreliable
Best Uses
- Boating
- Personal Watercraft
Comments about 2.5hp & 3.5hp 4 Stroke Outboards:
I have been using this motor for about 3 years. Suddenly, while running, the motor just quits and will not start for about 45 minutes. It left me stranded more than once. The repair shops can't find the problem.
Pros
Cons
- Unreliable
Best Uses
- Boating
Comments about 2.5hp & 3.5hp 4 Stroke Outboards:
This engine is hard to start and keep running out of the box. Back to Mercury service twice for carb replacement with no luck fixing the problems. Will not accelerate quickly and just quits while running for no reason. Have talked to several people with them and all have the same problems. Junk!
Pros
Cons
- BIG PROBLEMS WITH FEUL
- Unreliable
Best Uses
Comments about 2.5hp & 3.5hp 4 Stroke Outboards:
I USE IT ON MY 10' WEST MARINE INFLATABLE. I HAVE HAD ALOT OF TROUBLE WITH THE CARB. BECOMING CLOGGED. IT'S HARD TO GET NON-ETHONOL FUEL AND THIS ENGINE WILL CLOG WITHIN THE FIRST 10 HOURS IF YOU DON'T. I WISH THE MANUFACTURER HAD TAKEN THAT INTO CONSIDERATION WHEN THEY MADE THESE ENGINES.....BE FOREWARNED.....KEVIN O, IN BOSTON
Pros
- Easy Storage
- Easy To Use
- Lightweight
- Reliable
Cons
Best Uses
- Boating
Comments about 2.5hp & 3.5hp 4 Stroke Outboards:
engine starts easy and runs for 3+hours on 1 gallon of gas
Displaying reviews 1-10
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2.5hp & 3.5hp 4 Stroke Outboards
Product Specs
The West Advisor
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Merchant response: We are so sorry that you are not satisfied with your Mercury Marine outboard engine. Please consider contacting our Customer Care Department at 1-800-262-8464 to see if we can assist you with your issue.
(International customers please email catintl@westmarine.com or call 1-831-761-4800).