Building or upgrading all-terrain vehicles is always about balancing power, weight and terrain. marsh-moveThe challenge for a designer is to choose a power unit that not only pulls a heavy structure through the dirt, but also does it economically and reliably. A design error can turn a promising project into a pile of metal that sinks in the first serious puddle.
In today's world, the powertrains for homemade all-terrain vehicles are incredibly diverse, from classic gasoline-powered internal combustion engines from motorbikes and motorbikes to modern diesel units and even electric motors, each with its own unique advantages and disadvantages that must be considered when you're in the specific operating conditions of your future car.
In this article, we will discuss in detail the technical nuances of choice, ways to adapt various engines and secrets that will allow you to choose your own engine. swamp-boat We're going to look at not only the theory, but also the practical aspects of engine-to-drive docking, which is often a stumbling block for beginners.
Criteria for the choice of a power plant for an all-terrain vehicle
The first thing to decide on is the type of terrain and the weight of the structure. Engine power It should not be excessive, but its lack will lead to constant slippage and overheating. For light single structures, 6-9 horsepower is often enough, whereas heavy two-seat marshboats with kung require 13-15 hp and above.
The second critical parameter is the cooling system. Air cooling is easier to maintain and lighter in weight, making it a popular choice for the air cooling system. motorblock type neva or UgraHowever, with prolonged operation at low speeds in heavy mud, such a motor can quickly overheat. The liquid cooling characteristic of car engines and some motorcycles ensures temperature stability, but adds weight and complexity to the design of radiators and pipes.
The third aspect is the availability of parts and the maintenance of the field. Exotic engines can have excellent specifications, but if in the deep taiga the electronic control unit or a specific sensor fails, your expedition can end early. liphane, Honda Or Soviet motorcycle units.
- 🚜 Fuel type: Gasoline is easier to start in the cold, diesel is more economical and safer in storage.
- ❄️ Launch: The presence of an electric starter is critical for heavy machines, manual start-up is good as a backup option.
- ⚖️ Weight: The lighter the engine, the less pressure on the ground, which increases the permeability of the swamp.
- 🔧 Resource: Motor resource in the watch directly affects the durability of the entire design of the all-terrain vehicle.
⚠️ Attention: When choosing an engine, pay attention to the direction of rotation of the shaft. Many engines have a standard anti-clockwise rotation, but there are also reverse modifications that may require the entire transmission to be turned or the use of an additional gearbox.
Engines from motoblocks: classics of self-building
The most popular solution for beginner designers is the installation of the engine from the motorblockThis is due to availability, relatively low cost and ease of integration. liphane, cypore or Briggs & Stratton With 6 to 15 horsepower, the design is as simple as possible for lightweight single-seater marshmallows: the lower valve arrangement (OHV) provides the good torque needed to overcome the viscous ground.
However, using such engines, it is worth considering their features. Horizontal shaft It requires proper docking with a chain or belt gear. It is often necessary to install centrifugal clutch or use a standard gearbox, which increases the size of the power plant. In addition, air cooling systems of such engines require constant air flow, so when installed in a closed casing of the marshboat, you need to organize a forced blowout.
For more demanding tasks, two-cylinder engines from motorblocks, such as: Valeria or dentureThey have a significant thrust reserve, but their weight and dimensions may require reinforcement of the all-terrain vehicle frame, and installing such a unit turns a lightweight swamp into a full-fledged all-terrain amphibious vehicle capable of towing a trailer or carrying a winch.
☑️ Checking engine readiness for installation
The important thing is to refine the exhaust system: the regular mufflers of the motorblocks are often too loud, and their location can lead to sparks on dry grass or into the interior of the marshboat, it is recommended to make a remote muffler with a spark and remove the exhaust above the roof level or away from the driver.
Motorcycle engines and variators
Use of motorcycle engines, especially from Soviet equipment Iz, ural or DnieperThese engines are designed to work in heavy conditions, have air or mixed cooling and have a high resource. Two-stroke engines are simple, but voracious and smoky, whereas four-stroke oppositions.ural, Dnieper) provide excellent traction and reliability, although they are of considerable weight.
The key to this is the transmission, which is the most common way to use a scooter or motorcycle variator in conjunction with a chain transmission to the rear axle, and this allows for smooth gear ratio changes, which is critical for a swamp. Variator transmission protects the engine from overloads and allows you to effectively use power in a wide range of speeds.
Modern Chinese water-cooled engines (150-250 cc) are also being used, they are compact and powerful, but require a radiator installation, and the problem is solved by taking the radiator out into the incoming air flow zone or installing an electric fan that turns on automatically when heated.
| Type of engine | Power (hp) | Weight (kg) | Features |
|---|---|---|---|
| Motorblock (1 cylinder) | 6 - 9 | 12 - 16 | Simplicity, cheapness, air cooling |
| Motorblock (2 cylinders) | 12 - 18 | 25 - 35 | High traction, heavy weight, vibrations |
| Motorcycle (Izh/Ural) | 28 - 36 | 40 - 50 | Reliability, power reserve, complex docking |
| Scooter (150-250cc) | 10 - 20 | 15 - 20 | Compact, availability of a variator, need a radiator |
Secrets of Variator Setup
For a swamp, it's important to adjust the variator to maximum thrust, not speed, so you change the weight of the loads in the front pulley to heavier ones, and you put the belt tighter, so you can get the car out of the dirt more confidently, sacrificing maximum speed.
Automotive Engines: Power and Complexity
Installation of a car engine, for example, from Okey., tauria classic VAZIt's a major change in technology, and these swamps are becoming full-fledged all-terrain vehicles, capable of carrying 2-4 people and cargo. VAZ-1111 (Oka) is particularly popular because of its light weight (about 65 kg assembly) and the availability of spare parts. The four-cylinder engine provides smooth operation and sufficient power to install a homemade gearbox.
The main difficulty here is the coordination of the engine with the transmission. Automotive engines require the correct temperature regime, so the cooling system must be designed with the low speed of the swamp. The radiator is often carried forward, and an additional electric pump ("pump") is installed to circulate the fluid, since the regular one may not be able to cope at idle speeds.
The generator must also charge the battery even at low speeds if the winch, light and heat are to be used, and often standard generators are replaced with more powerful analogues from injection models or external voltage regulators are installed.
⚠️ Attention: When installing a car engine, be sure to provide reliable protection for the crankcase. On a swampboat, the risk of damaging the pallet against hidden roots or stones is extremely high, and losing oil away from civilization is equivalent to overhaul.
Electric motors: The silent revolution
Electrical mobility has also reached the marshlands. electric motors DC or motor wheels allow you to create silent and environmentally friendly all-terrain vehicles, ideal for hunters who want silence, or for use in protected areas, electric torque is available from the first rpm, which gives excellent start dynamics.
But the main limitation is battery capacity: Lithium-iron-phosphate (LiFePO4) batteries allow you to store a lot of energy at less weight, but they are expensive; lead-acid batteries are cheaper, but they can weigh half the weight of the entire swamp, which reduces the permeability on shaky ground. The calculation of autonomy should be carried out with a margin of at least 30%.
The advantage of the electric drive is the simplicity of the design: there is no exhaust system, a complex gearshift mechanism (often a direct drive or a simple gearbox is used) and the need for fuel. Maintenance is reduced to battery charge control and the state of contacts that must be reliably protected from moisture.
When using an electric motor, set a voltmeter with an alarm. A sudden discharge of the battery in the swamp can leave you without movement, and the sound will warn you of a critical charge level in advance.
Engine and transmission docking
The most difficult technical step is to connect the engine to the drive axle or tracked motor. If you use the motor from the motor block, you often use a standard gearbox, reworking its output shaft for chain transmission. transfer-box or homemade gearbox, which coordinates high engine speeds with low wheel speeds.
As an intermediate link, transmissions from motorcycles (IZH, Ural) or even from passenger cars (VAZ, Moskvich) are often used. The mechanical transmission allows you to choose the optimal gear for different conditions: the first and second for dirt and snow, the third and fourth for distillation on a hard road. It is important to ensure high-quality attachment of the units to the frame through vibration extinguishing elements (sylent blocks) so that the vibration does not destroy the welds.
Chain gears require regular lubrication and tension. For a swamp, it is better to use reinforced chains with a large pitch or a wedge belt, which is less sensitive to dirt and water, although it tends to slip when loads increase sharply. The driveshaft is more reliable, but more difficult to manufacture and requires precise alignment.
The main principle of docking: the gear ratio should be selected so that the engine operates in the range of maximum torque when driving on heavy ground, and not at maximum speeds.
Frequently Asked Questions (FAQ)
Which engine is better for a swamp: gasoline or diesel?
For homemade light and medium-sized swamps, the gasoline engine is preferable: it is lighter, easier to start in the cold and cheaper to maintain. It makes sense to only put diesel on heavy tracked all-terrain vehicles, where efficiency and fire safety are important, but its launch in winter requires preheating.
Can I use a lawnmower engine?
Technically possible, but not recommended: Lawn mower engines usually do not have a forced cooling system (fan) and are designed to operate with constant load. On a swampboat, where the modes of operation are torn, such a motor will quickly overheat and fail.
Do I need a gearbox if the engine is from the motor block?
Yes, almost always. The internal combustion engine's turnover (2500-3600 rpm) is too high for the swamp's driving wheels. The gearbox (or custom from the motor unit or homemade) is necessary to reduce revs and increase wheel torque.
How to protect the engine from water when overcoming fords?
You need to move the engine and gearbox sapons above the intended immersion level using extension hoses, and you should also treat the electrical contacts with moisture sprays and install protection on the air filter to prevent hydraulic shock.