Choosing a power plant for an inflatable boat is always a compromise between the speed, budget and physical parameters of the vessel. PVC 320 It's one of the most popular sizes on the market, combining enough capacity for two or three people with relatively compact dimensions assembled, which is why the question of which engine is best suited for this length remains one of the most debated among water engines of any level.
Not only can power be misguided to ruin the pleasure of cruising, it can also create dangerous situations on the water. A too weak unit will not bring the boat to full load plane, causing the engine to run at its limit. On the other hand, excessive thrust on a short base can lead to instability and even tipping over in sharp maneuvers.
In this article, we will analyze the technical details, analyze the market offers and help you make an informed decision. You will learn about the differences in engine types, the features of their installation on a transom width of 320 cm and understand what specifications should be paid attention to first when buying.
Technical limitations and power calculation for 320 cm length
The first thing a boat owner faces PVC 320 Inflatables manufacturers strictly regulate this parameter based on the strength of cylinders, bottom design and transom geometry. For a length of 320 cm, the standard range is 2 to 5 horsepower, although some reinforced models with an inflatable keel can withstand more powerful units.
The key factor here is not only the length, but also the loading capacity If you plan to fish alone with a minimum set of gear, you will have enough minimum values, but for two adults with load and equipment, you will need more serious traction to ensure that you get out to the planing, which saves fuel and reduces vibration.
⚠️ Attention: Never install a motor more powerful than the boat's passport, exceeding the limit can cause the transom to tear off under load, which can instantly sink the boat and lose the engine.
It is also important to consider the design of the bottom: Boats with a flat inflatable floor (PDND) or hard plywood floorboard behave differently. The hard bottom better holds the planing mode, allowing for more powerful motors, while the soft bottom extinguishes speed and requires more careful selection of the screw.
Two-stroke or four-stroke: the eternal dilemma of a water motor
In choosing between 2T and 4T For a 320 cm boat, most owners tend to lean toward two-stroke models, primarily due to their weight: two-strokes are much lighter, which is critical for carrying the motor by hand and mounting it on a light transom of an inflatable boat. Four-stroke counterparts, with better efficiency and silence, may be too heavy for such a small-boat.
Two-stroke engines require a fuel mix, which adds to the hassle, but provides excellent acceleration dynamics, are less sensitive to tilts during transportation and easier to repair in the field. Four-stroke engines They are cleaner, do not require mixing oil with gasoline and have lower fuel consumption over long distances, but their weight often becomes a decisive disadvantage.
If your boat is PVC 320 For short trips to the nearest backwater or fishing within a radius of 5-10 km from the base, a two-stroke will be the ideal choice. For long transitions where comfort and lack of exhaust odor are important, you can consider light four-stroke models, but you have to put up with their dimensions.
When buying a two-stroke engine, immediately purchase a measuring capacity for precise mixing of oil and gasoline. The proportion is usually 1:25 or 1:50 depending on the model, and you can not cast it by eye.
Overview of popular models of small class boats
The market of engines for small boats is represented by a variety of brands, from famous Japanese classics to affordable Chinese counterparts. Leaders in the power class up to 5 hp are traditionally considered to be the leaders of the class of power. Yamaha, Tohatsu and HondaThese brands have proven to be reliable and high build quality, although their cost can be comparable to the price of the boat itself.
The budget segment is actively occupied by such brands as Hidea, Parsun and Sea-ProOften structurally repeating the time-tested models of Japanese manufacturers, but assembled in other factories. For a boat 320 cm, such engines often become the “golden mean”, offering a decent ratio of price and quality.
Below is a comparative table of the specifications of popular models, which are often considered by owners of boats length of 320 cm:
| Motor model | Power (hp) | Weight (kg) | Type of engine | Features |
|---|---|---|---|---|
| Yamaha 2CMHS | 2.6 | 9.8 | 2T | Legendary reliability, built-in tank |
| Tohatsu M 3.5 B2S | 3.5 | 9.8 | 2T | Easyest in class, great start |
| Hidea HD 2.6FHS | 2.6 | 9.5 | 2T | Affordable price, copy of Yamaha |
| Honda BF 2.3 | 2.3 | 13.0 | 4T | Silent, economical, does not require a mixture |
When choosing a specific model, pay attention to the presence of a system. Electronic ignition (CDI)It's a squirrel that provides a stable spark and easy start, and it's also important to have neutrality, which is gear shifting, which makes it easier to maneuver in narrowness.
Selection criteria: weight, lower unit and management system
Motor weight is perhaps the most critical parameter for a boat. PVC 320Given that the boat itself weighs little, a heavy engine will shift the center of gravity to the stern, which will worsen the driving performance, the optimal weight is in the range of 9-13 kg. Anything heavier will require considerable effort in installation and may require strengthening the transom board.
The length of the lower unit (legs) also matters. Inflatable boats usually use a short lower unit (designated as S – Short), which is about 380-430 mm. Installing a motor with a long leg will lead to excessive immersion of the propeller, loss of speed and risk damage to the gearbox to the bottom or floating objects.
☑️ Check before buying the engine
The control system can be rampel or remote. For a length of 320 cm, remote control is practically not used, since it requires the laying of cables and the installation of the steering wheel, which weights the structure. The tiller located on the vomit of the motor allows you to control one hand and simultaneously control vomit, which is the standard for this class of boats.
Gleaning: Myths and Reality on Boat 320
Many buyers are wondering if their boat will come out. PVC 320 Gleaning is a mode of propulsion where the boat slides across the surface of the water, resting on it only part of the bottom, and for a boat of this length, gleaming is possible, but it depends heavily on loading and weight distribution.
With a motor of 2-3 hp, planing is possible only for one person of light weight. With increasing load, the boat will go into displacement mode, and the speed will fall to 5-7 km / h. Motors with a capacity of 4-5 hp are more confidently lead the vessel to the plane even with two passengers, if the design of the bottom allows.
⚠️ Attention: Trying to get a heavy boat to plane with a weak engine by fully opening the throttle can lead to cavitation of the propeller and overheating of the engine.
To improve the plane output, experienced water-engineers recommend moving loads (batteries, anchors, bags) closer to the bow of the boat, which raises the stern and reduces water resistance, and a properly selected propeller with optimal pitch plays an important role.
What is cavitation and how is it dangerous?
Cavitation is the formation of vapor bubbles in local pressure-reducing areas around the propeller blades. When these bubbles collapse, a shock wave occurs that can break down the screw metal and create noise. For boat 320, cavitation often occurs when the propeller is turned too high or when the propeller is raised too high above the water.
Service and preparation for the season
When you buy a motor, you should not forget that its durability depends on the quality of service. For two-stroke models, it is critical to use quality oil for water engines with the label. TC-W3Conventional motor oil for cars or motorcycles will lead to the formation of soot on the candle and piston rings, which will reduce the power and life of the engine.
After each operation, especially in salty or muddy water, the cooling system must be flushed with fresh water, or you can use a water tank with the engine leg down into it, which will prevent corrosion of the internal channels and impeller pump.
Storage also has its own peculiarities: If you leave the engine with fuel inside for a long time (more than a month), you either need to produce all the gasoline from the carburetor or add a fuel stabilizer, otherwise the light fractions of gasoline will evaporate, and the resinous residue will clog the carburetor's jellyplants, and the next season the engine will refuse to start.
Regular replacement of the fuel filter and checking the condition of the spark plug are the easiest and most effective ways to prevent engine failure away from shore.
Frequently Asked Questions (FAQ)
Can I put the 6 hp engine on the PVC 320 boat?
Technically, this is possible if the trunk of the boat is reinforced and can withstand the weight and thrust of such a motor. However, for a length of 320 cm this is often excessive: the boat will become unstable, will prowl, and the management will be complicated. In addition, GIMS may require registration of such a vessel if the power exceeds 5 hp (rules change, check the current regulations).
What kind of gasoline to pour into a two-stroke engine?
Use AI-92 or AI-95 gasoline with the octane number recommended by the manufacturer (usually indicated in the instructions). Gasoline should be fresh, no older than 1-2 months, Mix the oil with gasoline immediately before refueling or in a separate canister, carefully stirring.
Do I need to register the 320 with the engine in the GIMS?
According to the current legislation of the Russian Federation, registration is subject to small vessels with an engine of more than 8 kW (approximately 10.88 hp). Motors with a capacity of up to 5 hp (about 3.68 kW) registration does not require, which makes the bundle boat 320 + small engine very popular for fans who do not want to undergo bureaucratic procedures.
Why does the engine stop at high speeds?
Most often, the cause is a clogging of the fuel jellyclera, air sucking through the carburetor gaskets or a violation of the proportion of the mixture, it is also worth checking the fuel hose for bending and air filter condition, if the problem persists, you need to diagnose the ignition system.