outboard motor 8 hp 2x stroke: a complete review and tips for choice

Choosing a power unit for an inflatable floating craft is always about finding a compromise between power, weight and budget. outboard motor 8 hp 2x stroke Often becomes the middle-of-the-road solution that fishermen and tourists are looking for, and this power allows you to safely plane a boat with even two passengers on board, while remaining light enough to transport in the trunk of a car.

The two-stroke engine provides a number of unique advantages, the main of which is high specific power with minimal weight. Unlike four-stroke analogues, there is no complex lubrication system of the crankcase, which makes the design easier and cheaper to maintain. However, a potential buyer must clearly understand the features of the operation of such equipment to avoid disappointment in operation.

In this article, we will take a look at the technical details, compare popular manufacturers and give practical recommendations for running. A properly selected unit will last for years, giving pleasure from cruising, rather than problems with launching or repair. Let's find out why 8 horsepower is considered the standard for light inflatable boats.

Advantages of two-stroke 8 horsepower scheme

The main trump card that gives two-strokeFor 8 hp models, this is a critical parameter, as many users plan to often remove the engine from the transom and carry it manually. The lack of an oil crankcase and a complex gas distribution mechanism allows manufacturers to reduce the weight to 18-22 kg, which is a strong argument for owners of small PVC boats.

In addition, the two-stroke design provides a sharper response to the gas handle, which is especially important when maneuvering in difficult conditions, for example, when fishing in reed thickets or when moving against a strong current. Instant set of speeds It allows you to quickly respond to changes in the water environment, which can sometimes be a safety issue.

Maintenance of these engines is also simplified by the absence of many moving parts, there is no need to regularly change the oil in the engine, as it burns with the fuel, and this eliminates the risk of confusing the type of oil or forgetting to replace, which often happens to beginners with four-stroke models.

• 🚀 Minimum weight of the design, allowing one person to easily control the boat and the motor.
• ⚙️ Simplicity of design, ensuring high reliability and maintainability in the field.
• 💰 Lower cost of both the unit itself and its further maintenance.
• 🌊 The ability to transport in any position without the risk of leakage of technical fluids.

⚠️ Warning: Two-stroke engines require precise compliance with the mixing proportions of gasoline and oil. Using pure gasoline will lead to piston group bullies and expensive repairs within minutes of operation.

Despite the seeming simplicity, ignition Electronically controlled advance ignition allows you to optimize the combustion of the mixture at different speeds, reducing fuel consumption and reducing exhaust toxicity, which makes modern two-strokes not as voracious as their predecessors from the last century.

Technical specifications and fuel consumption

When choosing an 8 hp unit, it is important to pay attention not only to the declared power, but also to the cylinder displacement. Usually this parameter varies from 150 to 200 cubic centimeters. It is the volume and compression ratio that determine the traction specifications at low revs, which is often more important for fishing than the maximum speed.

Fuel consumption is the second most important issue that owners are concerned about. 8 hp outboard motor. It consumes about 2.5 to 3.5 liters of fuel per hour when driving at full speeds. In economical mode, when the boat goes at transition speeds, the flow can be reduced to 1.5 liters. For comparison, a four-stroke analog of the same power will be more economical by about 20-30%, but the difference in weight can offset this savings.

The type of cooling system is also important: most models have a forced water cooling system, where water is drawn from the reservoir through the water intake and circulates around the cylinder, and you need to monitor the control jet ("urinal"), which should be visible when the engine is running.

Why is it deaf to singles?

A common cause is overgrowth of fuel channels or misconfiguring of the carburetor, and it can also be a problem in clogging the cooling system, causing the thermal sensor to go off or overheating.

Below is a comparison table of the specifications of popular models on the market so you can better navigate the numbers.

Motor model	Workload (cm3)	Weight (kg)	Fuel consumption (L/h)	Type of management
Tohatsu M8B	155	22.0	2.4	rumble
Yamaha 8CMHS	169	24.5	2.6	rumble
Mercury 8M	169	24.0	2.7	rumble
Hidea HD8FHS	169	23.5	2.8	rumble

It is worth noting that the actual flow rate always depends on many factors: the weight of the boat, the state of the bottom, wind and excitement on the body of water, so these figures should be taken as indicative values for calm water.

Comparison of manufacturers: Tohatsu, Yamaha, Hidea and others

The outboard motor market is saturated with various brands, but leaders in the 8 hp segment are traditionally considered to be Japanese companies and their licensed copies. Tohatsu Often referred to as the "king of two-strokes" because of the incredible reliability of their piston bands, many other brands, including Mercury, actually buy engines from Tohatsu and put their logos on them.

Yamaha It offers products that are famous for their environmental friendliness and sophisticated ergonomics, and their engines often feature exhaust purification systems that make the exhaust less visible and smelly, which can be critical for anglers, because the pungent smell of gasoline can scare off cautious fish.

Chinese brands such as HideaParsun or Sea-Pro have made a huge leap in quality in recent years, often hiding the same components as Japanese giants but built in other factories, with price differences as high as 30-40%, making them extremely attractive for the budget segment.

• 🇯🇵 Tohatsu/Mercury: Reliability standard, high repairability, expensive spare parts.
• 🇯🇵 Yamaha: Excellent traction at the bottom, low vibration, high price.
• 🇨🇳 Hidea/Parsun: The best price/quality ratio, available consumables, sometimes there is a scattering as an assembly.
• 🇷🇺 Flagship/Micran: Russian assemblies (often based on Chinese components), adapted to our conditions, available service support.

⚠️ Warning: When buying a Chinese engine, be sure to check for an official service book and warranty shops in your area. Without service support, savings on purchase can turn into problems during repairs.

Choosing between brands, don't just chase a well-known name: often a less-than-promoted brand offers quality for less money, investing in metal rather than marketing.

Rules for running a new engine

The scoring is the most important stage in the life of a new boat-engineIt's in the first hours of operation that the rubbing parts are used, and how this process works depends on the life of the engine as a whole, and neglect of the rules of running is the main cause of early breakdowns and loss of warranty.

The process usually takes about 10 hours of operation or production of 3-4 tanks of the fuel mixture. During this time, it is forbidden to give full gas. It is recommended to adhere to the regime when the throttle is open no more than 50-70%. This allows the piston rings to fit correctly to the walls of the cylinder, creating the necessary compression.

It is also important to use a richer mixture during the break-in, for this purpose, it is recommended to add more oil to the first tanks than is indicated in the instructions for normal use, for example, if the standard ratio is 1:50, then it is better to do 1:40 or even 1:25 for the break-in, if the manufacturer requires it.

Remember to control the engine temperature. When running, the engine can warm more than usual, so watch the cooling jet. If the jet has disappeared or became intermittent, immediately turn off the engine and check the water intake for debris.

After completing the first 10 hours, be sure to carry out maintenance: replace the spark plug, check the tightening of all bolt joints (especially on lower unit) and lubricate the slate connection of the paddle shaft.

Fuel mixture preparation and operation

The basis for a long life of a two-stroke is the right fuel. Gasoline must be fresh, preferably AI-95, because it contains less impurities and burns better. Use of old gasoline, which has been in the canister for more than 2-3 months, is unacceptable, since it loses its octane properties and forms a resinous plaque.

Oil should be used only special, with markings TC-W3Automotive oils (M-10, M-12 and analogues) are strictly prohibited, as they do not burn completely at the combustion temperature of gasoline, forming a soak on candles and pistons. The mixing ratio is usually 1:50 (20 ml of oil per 1 liter of gasoline) for new engines and 1:40 for break-in or old engines.

The mixing process should take place in a separate clean tank, not directly in the engine tank. Pour half the gasoline, add the whole oil norm, shake, then add the rest of the gasoline and mix again. This ensures the mixture is homogeneous.

Formula of calculation:
Amount of oil (ml) = (Volume of gasoline (l) / Proportion) * 1000
Example for 10 liters of gasoline and a ratio of 1:50:
(10/50) * 1000 = 200 ml of oil

When you store an outboard motor in the off-season, you need to make all the fuel out of the carburetor, so after the last walk, shut the fuel tap and let the engine run until it stops, and the gasoline left in the carburetor will evaporate over the winter, leaving a resinous sludge that will clog the jelly.

⚠️ Warning: Never store a full-fuel engine for more than one month. The gasoline oxidizes and loses properties, which will lead to a difficult start in the spring.

Frequent malfunctions and their elimination

Even the most reliable 8 hp outboard motor. Most often, owners face difficult start-ups or unstable idling, and 80 percent of the time, it's because of a fuel system, whether it's a contaminated carburetor, old fuel, or the wrong proportion of the mixture.

Another common problem is overheating. If you notice that the engine has lost power or made a strange sound, check the cooling system. Often, sand, algae or a plastic bag enters the water intake, blocking the water supply. Cleaning the water intake takes a couple of minutes, but saves from major repairs.

Ignition problems are less common, but they are also possible. A candle can tell you about the state of the engine: black soda indicates a rich mixture (a lot of oil), white indicates a poor one (a little oil or air sucking), the normal color of a candle insulator is brick-brown.

• 🔥 The engine won't start: check the presence of a spark, the quality of the mixture, the condition of the candle.
• 🌊 No telltale jet: Clean the pump hole, check the impeller.
• 💨 Smoke on singles: adjust the carburetor, check the quality of the oil.
• 🔊 Engine knock: immediately jam, check the rod and bearings.

What do I do if the engine is drowned?

If the motor has been in the water for a short time, you need to immediately remove the candles, blow the cylinders with the starter (to drive the water out), rinse the carburetor and the ignition system with alcohol, lubricate all available units and try to start.

Regular prevention and careful attention to the sounds and behavior of the engine avoid most serious breakdowns.

Frequently Asked Questions (FAQ)

How many liters per hour does the 8 hp engine consume at full gas?

On average, the consumption is about 2.5-3.5 liters of fuel mixture per hour at full load. On an economical run (about 3000-4000 rpm), the consumption can be reduced to 1.5-2 liters.

Can I keep a two-stroke motor lying on my side?

Yes, two-stroke motors can be transported and stored in any position, as there is no oil in the crankcase, but it is recommended to still fix it in an upright position or on a certain side (usually right when viewed from the side of the lower unit) to avoid water entering the muffler or carburetor.

Which oil is better to pour: mineral or synthetic?

For modern motors, it is better to use semi-synthetic or synthetic oils labeled TC-W3. They form less soak and better lubricate friction knots, which is especially important at high revs.

Do I need to dilute the gasoline for running?

Yes, for the breaking in, the oil proportion is often increased, and if the standard ratio is 1:50, then it is recommended to break-in 1:40 or 1:25 depending on the manufacturer's recommendations, which provides better lubrication during the finishing period.

Why does the engine stop when the gas is opened?

It's probably idling or there's water in the fuel, and it could be because the screw quality of the mixture on the carburetor is not adjusted correctly, so try to clean the carburetor and replace the fuel filter.