Choosing an outboard motor is always about finding a balance between power, weight and reliability, and in this context, it is a good idea to choose a motor. Nissan Marin engine 9.8 This model, known for its exceptional survivability and simplicity of construction, has become a favorite among owners of PVC boats and light aluminum boats, unlike its more powerful counterparts, this unit does not require complex maintenance, but it can provide a confident exit to planing with two adult passengers on board.
It is important to understand that technically this engine is the direct heir to the legendary platform. Tohatsu M9.8BIt's made in the same Japanese factories, but with different labels and colors, and it's this feature that makes it attractive for those who are looking for a time-tested "Japanese" assembly, but are not willing to overpay for the brand. The Nissan Marin 9.8 is the only two-stroke engine in its class that is officially certified to run on 92 octane fuel without losing the life of the piston group.
In this article, we will explore the technical details, features of running and secrets of durability of this popular unit, you will learn why many experienced water engines choose this model for serious operation away from civilization.
Technical specifications and design features
At the heart of the power plant is a two-stroke internal combustion engine with a displacement of 169 cubic centimeters, which is a configuration that allows you to shoot almost 10 horsepower, which is a boundary value for many water bodies with power limitations. carburetor It is simple and reliable, devoid of sophisticated electronics, which is critical for fishing in remote areas.
The engine weighs just 25.5kg in dry, making it one of the lightest in the 10bhp class, making it easy to carry to one person or quickly set on a boat transom without assistance. The ignition system uses electronic CDI control, which requires no adjustment of gaps and provides a stable spark even at low revs.
⚠️ Warning: Despite the simplicity of the design, the cooling system requires constant monitoring. Never start the engine without diving into water or connecting to a forced water supply system, as this will cause instant overheating and deformation of the unit head.
The exhaust system deserves special attention: the exhaust gases are discharged through the lower unit, which reduces the noise and vibration on the transom, but it is also the lower unit that often becomes the object of corrosion when used in salt water, if not washed with fresh water in a timely manner after each operation.
Advantages of the model over competitors
Why? Nissan Marin engine 9.8 And the answer lies in its power density and maintainability. The two-stroke cycle provides excellent torque at low revs, allowing the boat to plane faster than the four-strokes of similar power.
In addition, the lack of a crankcase with oil makes transportation easier: the engine can be transported in any position – on the side, upside down or on any side, without fear of leaking oil or getting into the combustion chamber, making it an ideal choice for owners of small inflatable boats, who often store equipment in the garage or trunk of a car.
The list of key advantages is as follows:
- 🚀 High specific power and excellent acceleration dynamics.
- 🛠 Easy maintenance and availability of spare parts around the world.
- 🎒 The ability to transport in any position without draining oil.
- 💰 The optimal ratio of price and reliability of Japanese production.
And resource is also important. With proper running and high-quality fuel, a piston group can walk hundreds of hours without having to overhaul, and many owners note that the engine retains traction even after several seasons of active use.
Fuel consumption and efficiency of operation
The question of fuel consumption is always acute, especially for those who are used to spending all day on the water. Nissan Marine 9.8 It consumes about 3-3.5 liters of gasoline per hour at full load on a combined cycle, and at cruising speeds of about 70-80% of maximum power, the flow rate is reduced to a comfortable 2-2.5 liters.
The ratio of oil to gasoline is strictly observed to prepare the fuel mixture. Usually a ratio of 1:50 is recommended when using modern synthetic oils for two-stroke engines. Using poor-quality oil or a violation of proportions can lead to the formation of soak on the candle and piston, which will adversely affect performance.
For comparison of efficiency, you can refer to the table, which presents the averaged flow rates depending on the mode of operation:
| Mode of work | Turnover (rpm) | Expenditure (L/hour) | Speed (km/h)* |
|---|---|---|---|
| Idle move | 1000-1500 | 0.8 - 1.0 | 5 - 7 |
| trolling | 2500-3000 | 1.5 - 1.8 | 12 - 15 |
| Cruiser | 4000-4500 | 2.5 - 2.8 | 25 - 30 |
| Full gas. | 5500-6000 | 3.2 - 3.6 | 35 - 40 |
* Speed is indicated approximately for a PVC boat with a length of 3.2-3.6 meters with a load of 150 kg. As can be seen from the data, the motor is quite economical for its class, especially when compared with four-stroke analogues, which at low speeds can consume more due to the peculiarities of the pump and friction of internal mechanisms.
breaking in process: step-by-step instructions
Getting the right break-in is the foundation of a long life for your engine, and neglecting this stage can reduce your lifespan by a few times. Nissan Marin 9.8 engine It takes about 10 hours of work and requires strict compliance with temporary interts and loads.
The first 10 minutes of work should be done idling, so that all the rubbing parts are rubbed together at minimum temperatures, and then you can move on to short-term speed increases, but not more than 2000-2500 per minute.
☑️ Checklist of successful break-in
During a period of 2 to 10 hours of operation, short-term (no more than 2 minutes) opening of the throttle at full power is allowed, but the main mode should be 70% of the maximum. This allows the piston rings to sit properly in the grooves, providing the necessary compression in the future.
⚠️ Attention: It is strictly forbidden to work long-term at constant speeds (for example, when trolling) during the first 10 hours.
At the end of the break-in, be sure to replace the oil in the gearbox, even if it looks clean. It may contain the products of the primary grinding of the gears. It is also recommended to check the tightening of all bolt joints, as vibration in the first hours of operation could weaken them.
Maintenance and typical faults
Regular maintenance avoids most problems. The main enemy of two-stroke engines is poor fuel and water in the gas tank. Periodically check the fuel filter and blow the system with compressed air. The spark plug should be twisted and checked every 50 hours or at the beginning of each season.
One of the typical problems can be difficult to start after a long downtime. Often the reason lies in sticking petal valves or loss of tightness of the crankshaft glands. If the engine is "troit" or does not develop full power, first check the condition. carburetor And there's an air suction in the inlet tract.
The cooling system also requires attention. Control the stream of water coming out of the control hole. If it becomes weaker or disappears, immediately turn off the engine. Maybe the cooling shirt clogged or the impeller wore out. Replacing the impeller is a standard procedure that is recommended every 2-3 seasons.
How do we extend the life of the ossilk?
Crackshaft coils often fail due to skewed dayswood when installed. Always make sure the motor is strictly vertical on the transom. Also use a special lower unit lubricant to prevent rubber from drying out during storage.
Don't forget to lubricate the knots. All lubrication points specified in the manual (usually the gearshift axes and the rotary mechanism) should be treated with lithium lubrication regularly, which will protect the metal surfaces from corrosion and ensure easy control of the tiller.
Tuning and reworking: is the game worth the effort?
Owners often think about increasing power or comfort of operation. Nissan Marine 9.8 This is a more efficient carburetor and a change in timing, but it requires a lot of knowledge and can cause the motor to fail quickly if it's done unprofessionally.
A more sensible approach is to improve ergonomics, by installing an elongated humming wheel, a comfortable gas handle, or a windshield carburetor casing (to avoid freezing in winter) is much more useful in real-world operation, and many people are changing the standard propeller to a more "traction" or "speed" one depending on the type of boat and the tasks.
Install a transparent_inline_filter with a sump on the fuel line, which will allow you to visually monitor the quality of the fuel and the availability of water in the system on the go, which is especially important when refueling at untested gas stations.
If you plan to use the motor in winter, be sure to take care of the thermal insulation of the carburetor. diffuser freezing is a common problem of two-strokes at low temperatures, leading to impoverishment of the mixture and engine stop.
Comparison with analogues and final conclusions
There are several direct competitors on the market, such as Yamaha 9.9 and Tohatsu 9.8. Yamaha often wins in terms of availability of service and parts in certain regions, but can be more expensive. Tohatsu is essentially Nissan's twin, but with a different emblem, the choice between them often comes down to the price in a particular store and the availability of warranty support.
The card card. Nissan Marin 9.8 engine It's a time-tested design that's been virtually unchanged for decades, which means that any skilled motorist knows how to fix it, and parts can be found even in remote parts of the country, and for a fisherman or hunter who needs a "forever" technique, it's perfect.
So in conclusion, this motor is a tool, not a toy, and it won't impress you with the quietness of the work or the environmental friendliness, but it will take you from point A to point B and bring you back, even if you're hundreds of miles away from civilization.
The Nissan Marine 9.8 is the benchmark of reliability in the lightweight two-stroke class, combining minimum weight, maintainability and sufficient power for planing light boats.
Frequently Asked Questions (FAQ)
Can this motor be used in salt water?
Yes, the motor is adapted to work in salt water, but requires a mandatory freshwater rinse after each exit.
Which oil is better to put in the mixture?
It is recommended to use high-quality semi-synthetic or synthetic oils for two-stroke outboard motors labeled TC-W3. Mineral oils are acceptable, but require more frequent replacement and give more soak.
Why does the engine stop at high speeds?
The most likely cause is clogging of the carburetor's jellyplates, water entering the fuel tank or a violation of the ventilation of the fuel tank (check the valve in the lid).
Is it possible to register this engine in GIMS?
Yes, since the engine power is less than 10 hp (formally 9.8), it does not require registration with the GIMS and the availability of rights to operate a small vessel, if the total power of all engines on the boat does not exceed 10 hp.