Choosing an outboard motor for an inflatable vessel is not just about buying machinery, it's about finding the perfect balance between weight, power and comfort. Many beginners make the mistake of focusing only on price or brand, forgetting that they're not the only ones who are going to be able to get the best out of the way. conveyance It's critical to PVC boats, and unlike metal boats, where the engine weight is secondary, in an inflatable boat, every extra kilogram is felt when you're going down and dragging along the shore.
The modern market offers a huge range of solutions, from lightweight electric tractors to powerful gasoline units that can bring a boat to planing in seconds. What engine to buy for a PVC boat In your case, you need to analyze the use cases, whether you're going to fish in quiet backwaters, drive at high speeds in open water, or make long journeys, and the answers to those questions will determine the type of engine, its tact and the power it needs.
In this article, we will take a closer look at the technical details, compare two-stroke and four-stroke models, and look at time-tested brands. You will learn how to correctly calculate the thrust for your boat and avoid common mistakes that can cost you money and ruin the experience of swimming.
Calculation of the required power: formula and nuances
The first thing the boat owner encounters is the numbers on the transan marker, and the manufacturer always gives two values: minimum and maximum engine power. maximum capacity It's not really possible, because it's a safety issue, but it's not always efficient to put a lower power motor, especially if you're planning to go full load.
There is a simple empirical formula to estimate the power required. For every 25-30 kg of total weight (boat + motor + equipment + people), it takes 1 horsepower to confidently enter planing mode. For example, if a boat weighs 40 kg, engine 25 kg, two passengers 80 kg and equipment 30 kg, the total weight will be 255 kg. Divided by 25 and get about 10 hp This means that the engine will become 9.9 hp. optimal solution for such a complete set, providing a thrust reserve.
For boats up to 3 meters long, 5-8 hp is often enough, but if the length is more than 3.5 meters, power requirements increase dramatically. A weak motor on a long boat will cause the boat to dig a wave with its nose without getting up to plane, which increases fuel consumption and engine wear.
And don't forget the margin. If you plan to go full load or against the current and wind often, you'd better go with a 20 to 30 percent margin, which will extend the life of the engine, because it won't run to its limit all the time.
The eternal dilemma: two-stroke (2T) or four-stroke (4T) motor
The debate over which type of engine is better has not subsided for decades. Two-stroke engines Traditionally lighter than their four-stroke counterparts of the same power, which is a crucial factor for owners of lightweight PVC boats: they are easier to maintain, cheaper to repair and less sensitive to fuel quality, although they require a mixture of gasoline and oil.
On the other hand, four-stroke They're much less fuel efficient and they're quieter, they don't require oil to be mixed with gasoline, which makes it easier to refuel in the field, but they can be 30 to 50 percent higher in weight, which makes them less attractive for small boats, where mobility is important.
- 🔥 2T engines: High specific power, fast acceleration, less weight, the need to mix oil.
- 💧 4T engines: Economy, low noise, clean exhaust, more weight and dimensions.
- 💰 Cost of ownership: 2T is cheaper to buy, 4T is cheaper to operate at long distances.
The myth of fuel consumption
Is it true that 2Ts eat twice as much? In practice, a modern two-stroke engine with an E-TEC or OptiMax system only consumes 15-20% more than a four-stroke sibling when driving actively, the difference becomes noticeable only on small strokes, where the 4T is really more economical.
If you choose to go for a few hours, you'll be able to see the difference in fuel consumption, and the weight of a 2T engine will be a plus, and if you're on a multi-day expedition, every liter of gasoline counts, and the noise can scare the fish away. four-stroke It's a more rational choice.
Overview of popular brands and model ranges
The outboard motor market is divided into three segments: premium (Japan, USA), medium (Chinese factories under the control of brands) and budget. Yamaha and TohatsuJapanese units are famous for their reliability and liquidity in the secondary market.
Chinese brands such as Hidea, Parsun and Sea-ProThey've made a huge leap in quality in recent years, and often have the same cylinder blocks inside their shells as the Japanese, but with simpler electronics, which makes them a great alternative for those looking for a balance of value.
| Brand | Brand country | Features | Price segment |
|---|---|---|---|
| Yamaha | Japan | High reliability, expensive TO | Premium |
| Tohatsu | Japan | Lightweight 2T motors, simplicity | Highly |
| Hidea | China | Yamaha copies, available spare parts | Medium. |
| Suzuki | Japan | Economical 4T, good 2T | Highly |
When buying an engine of an unknown brand, it is important to pay attention to the presence of service centers in your region. Parts availability The engine may be cheap, but if the CDI unit burns down and waits two months from China, the savings turn into losses.
When buying a Chinese engine, check the carburetor model and ignition system immediately, and they are often unified copies of Yamaha, which makes it easy to find remixes in regular motorcycle stores.
Electrical traction: an alternative to gasoline
In recent years electric motors They're not a toy for kids, they're a serious tool for anglers, they're perfect for quiet fishing, where the sound of an internal combustion engine is not acceptable, and the lack of vibration and exhaust makes them environmentally friendly and comfortable.
The main question when choosing an electric motor is battery capacity. Lead acid batteries are heavy and afraid of deep discharge, whereas lithium iron phosphate (LiFePO4) are lightweight, durable, but much more expensive. Electric motor power is measured in pounds of thrust (lbs), where 1 lb is approximately equal to 0.45 kg of thrust.
⚠️ Warning: Don't use electric motor starter batteries in cars! They're not designed to give you long-term current and will fail quickly. Only buy Deep Cycle traction batteries.
For PVC boats up to 3.6 meters long and winds up to 3-4 points, there are enough engines with thrust 30-40 lbs. They allow you to move at a speed of 5-7 km / h for 4-6 hours. However, it is worth understanding that the electric motor is not designed to plane and get on the water against a strong current with full load.
☑️ Check before buying an electric motor
Train and installation: critical moments
Proper installation of the engine is the key not only to speed, but also safety. Transcent height If the boat manufacturer's recommendations are strictly followed, if the lower unit is submerged too deep, the water resistance will increase and the speed will drop, if it is too high, the air will start to suck and the engine will overheat.
For powerful engines (from 10 hp) on PVC boats, the use of cross-plate It distributes the load from the lower unit over a large area of the tank, preventing the trunk bag from squeezing and deforming, and without the stove, a powerful motor can simply eat the soft transomb during the active season.
The motor's attachment must be reliable. Use only regular rods to keep them tight. Check the screws' tightening regularly, because vibration has the property of weakening the connections. differentiation (engine angle) so that the boat goes smoothly, without burrowing its nose or lifting it excessively.
⚠️ Warning: Never run the motor out of water, even for a few seconds, and this is guaranteed to overheat and destroy the impeller of the water pump, as the rubber parts will not withstand dry friction.
Transportation and storage of equipment
Owning a outboard motor requires proper storage, and after every run on the water, especially if it was salt water, you have to flush the cooling system with fresh water, and corrosion is the enemy of any technology, and neglecting washing reduces the engine life by many times.
When transporting in the trunk of a car, it is better to store the engine in an upright position or on a certain side (as indicated in the instructions), so that the oil does not leak into the combustion chamber or muffler. For 4T engines, this is especially true, since the oil is in the crankcase and when tilted can leak through the sapoon.
The golden rule of storage: If you don't plan to use the motor for more than a month, be sure to drain the fuel from the carburetor or use a fuel stabilizer. Gasoline loses its properties in 30 days and turns into a jelly jelly tar.
Store the engine in a dry room, protecting it from dust with a cover. Do not leave the equipment in the cold without extreme necessity, although modern engines and designed to work in the cold, rubber seals and plastic can suffer from temperature changes and ultraviolet light with prolonged downtime in the sun.
Frequently Asked Questions (FAQ)
Can I put a 15-horsepower engine on a boat with a marking of max. 10 hp?
Theoretically, it can, but it's extremely dangerous and illegal, because the boat's tracker will not withstand the increased load and may burst at speed, leading to flooding, and it violates GIMS registration rules and can result in fines or confiscation.
What kind of gasoline to pour into a two-stroke engine: 92nd or 95th?
Most manufacturers recommend AI-92, as it contains less alcohols and is more stable when stored. High-octane 95th gasoline can contain ethanol, which destroys the rubber seals of the carburetor and promotes condensation.
Do I need to run a new engine?
Yes, it's mandatory for any new engine, be it a 2T or a 4T. It's usually 10 hours of operation at different speeds, mostly average speeds, and it allows the piston group and bearings to get clean, providing the declared resource.
Why does the engine stop at idle speed?
There can be several reasons: a polluted carburetor, air sucking through the glands, an incorrectly exposed ignition angle or a poor quality fuel mixture. Often the problem is solved by cleaning the jelly and adjusting the quality of the screw mixture.