The legendary Soviet cargo scooter Tula Ant But the native two-stroke engine often fails to cope with modern loads, requiring constant oil in gasoline and frequent replacement of the piston group. Owners are increasingly thinking about replacing their vehicle heart with a more reliable and economical Chinese four-stroke counterpart, a process known as a swap that requires serious preparation, but the result is worth it.
The main difficulty is that the regular seat and shaft of the engine TGA-200 Designably different from the standard Chinese engines of the series Lifan or ZongshenYou're going to have to do welding, redesign the exhaust system, and maybe replace the CVT or gearbox, and it's important to understand that just bolting it won't work here, it's going to require engineering and basic plumbing skills.
In this article, we'll look at all the stages of your truck transformation, and we'll look at the right donor, the nuances of welding the frame, the alignment of the transmission, and the finer points of setting up the fuel system. engine swap Not only will it prolong the life of the technology, but also make its operation much more comfortable and environmentally friendly.
Selection of power unit and compatibility assessment
The first step is to find the right donor, the most popular solution for the donor. Ant. These are engines with a capacity of 200-250 cubic centimeters. Lifan 170F or ZS168F They have proven to be reliable and unpretentious units, and the key here is the diameter of the shaft and its departure, because this depends on the possibility of docking with the native transmission or the need for its complete replacement.
When choosing, pay attention to the direction of rotation of the shaft. Standard motors for motorblocks often have a counterclockwise rotation shaft, whereas for Ant. Clockwise direction (if the native box is retained) or specific clutch layout is critical, and motors with integrated gearbox and automatic clutch are often installed on Chinese scooters, making integration easier.
Don't forget to check the overall dimensions. Chinese "horizontal" can be wider than the native engine. TGA-200This will require the engine compartment to be expanded or the tank shifted, and the new unit must not be overpowered by the frame and braking system, otherwise it will be too much. torque It can simply break the drive elements or make the control dangerous.
- 🔧 Engine capacity: optimally 196-250 cc to maintain the balance of power and weight.
- ⚙️ Type of shaft: pay attention to the presence of veneer and thread under the nut of the CVT attachment.
- 📏 Dimensions: Measure the free space in the engine compartment before buying.
- 💰 Cost: Consider the budget not only for the engine, but also for the associated parts for installation.
⚠️ Warning: Buying an undocumented engine, be sure to check and no foreign knocks by swiping the shaft with your hand. Chinese engines can have a factory defect that will only open after installation.
Refining the frame and manufacturing of the transition plate
The most time-consuming phase is mechanical adaptation. Ant. You will need to make a transition plate (adapter) of steel thickness of at least 8-10 mm. The use of thinner metal is unacceptable, since vibrations and loads when driving on the road will quickly lead to the destruction of the mount.
The process begins with the dismantling of the old engine and the thorough cleaning of the landing place, and then the new engine is positioned so that the axis of its output shaft perfectly matches the axis of the input shaft of the transmission. Ant.Any shift will cause the chain gear or belt to wear rapidly, and also vibrations, and after centering, the bolts are marked.
To fix the plate to the frame often requires welding additional brackets. If you do not have the skills of a welder, it is better to contact a professional workshop, since the quality of the seam directly affects the quality of the weld. safetyAfter welding, be sure to clean the seams and coat the metal with anti-corrosion primer and paint.
☑️ Preparation for welding
It's important to consider the thermal expansion of the metal. When the engine is heated, the geometry of the frame can change slightly, so don't tighten the bolts "deadly" until you finally check the work on the hot one. Use growers or counternuts so that the vibration does not weaken the connections.
Integration of transmission and drive
Docking of the new engine with the native gearbox Ant. The shafts are rarely the same in length and diameter, often have to use a transition coupling or order a special shaft from the turner, the alternative is to install a ready-made variator assembly from the scooter, which requires reworking the rear pendulum mount.
If you have a native 4-speed gearbox, make sure that the clutch of the new engine correctly interacts with the switching mechanism. In some cases, you have to completely abandon the foot switch and bring the clutch control to the steering lever, which changes the ergonomics, but simplifies the design.
Chain gear requires special attention. The step of the new motor's chain may differ from the step of the chain. Ant.So you change both stars and the chain to a donor motor kit, and you waste the seat under a big star on the output shaft of the gearbox, and the tension of the chain is controlled by moving the engine on the sled or by installing the tensioner.
| Parameter | Native TGA-200 | Chinese analogue (170F) | Recommendation |
|---|---|---|---|
| Type of engine | two-stroke | four-stroke | Replace oil every 50 hours |
| Power | ~5.5 hp | ~6.5 hp | Check the load on the frame |
| Clutch. | Friction in oil | often centrifugal | Adaptation of the drive is required |
| Cooling | Forced (fan) | Airborne | Provide airflow |
The problem with the shaft length
If the shaft of the Chinese engine is too short, do not build it up with welding - this will disturb the balance. It is better to use the transition sleeve with veneer ordered from the turner, or replace the shaft entirely with an elongated analogue from the motor unit.
Keep in mind the lubrication. If you use an open circuit, install a protective casing, otherwise the dirt and sand will quickly disable the gear. Check the glands regularly on the output shaft, as they may experience unusual loads when installing a new motor.
Modernization of fuel system and exhaust
A four-stroke engine requires clean gasoline without a mixture of oil, so you either have to completely wash the old tank of oil deposits, which is extremely time-consuming, or install an additional tank for clean fuel, the second option is preferable, since it guarantees the purity of the fuel and retains the ability to quickly reverse the engine.
The carburetor of a new engine often requires adjustment to specific operating conditions. Ant. It is recommended to install an additional filter for fine fuel cleaning in front of the carburetor.
The exhaust system is another node to refine. Ant. It's not going to be geometry or capacity, you're going to have to boil a new manifold or use corrugated stainless steel to connect the cylinder head to a universal silencer, and it's important to keep the exhaust gases away from the driver, especially with the loading of the equipment.
- ⛽ Fuel filter: Required to be installed as Chinese carburetors are sensitive to debris.
- 🔇 Smooth: Choose a model with a sparkler, especially if you plan to drive in the fields.
- 🔌 Cords: the length of the native gas cables may not be enough, lengthening or replacement will be required.
⚠️ Attention: An AI-92 petrol with an octane rating below 90 can cause a high compression four-stroke engine to detonate. Use only quality fuel to avoid valve burnout.
To solve the problem temporarily, you can use a 5-liter plastic canister attached to the normal tank, which will allow you to test the engine in operation before making a stationary mount.
Electricity and start-up system
Chinese engines are often equipped with an electric starter and a lighting coil, which requires battery connection. Native 6-volt network Ant. It's a little weak to run safely, so it's wise to switch to a 12-volt system, which requires replacing the light bulb, the ignition coil, and installing a new battery.
The circuitry is quite simple: plus the generator goes to the battery through a rectifier-regulator, which is often built into the Chinese motor. ants The body is not a minus, but an insulated wiring is used.
If the electric starter is not provided or the battery sits in the field, make sure that the manual starter (drift) is easy to access. On some models of engines, the starter handle is poorly located and you have to move or replace it with an elongated one.
Check the oil sensor. Many Chinese engines have a low-oil-proof engine. Ant. (especially when climbing uphill), the sensor can break the circuit and the engine will stall, in which case owners carefully lock the sensor, but this requires strict control of the oil level manually.
First start and run of the new unit
Once all the knots are assembled, there comes a moment of truth. Before you first start, be sure to put oil in the engine crankcase to the desired level. Scroll the engine manually (kick starter) several times to make sure there is no jamming and compression present.
Start the engine and let it warm up at idle speeds. Listen carefully: there should be no knocking, no whistling of the belt or the clang of the chain. Check the connection of the exhaust system for leakage. After warming up, turn off the engine and after 10 minutes check the oil level - it may have changed after filling the channels.
The break-in of a new four-stroke engine is different from the break-in of a two-stroke. Don't give the first 5-8 hours a full load. Move with a load not exceeding 50% of the nominal value, and avoid long work at maximum speed. After the first 500 km of run, be sure to replace the oil, as it will have a lot of metal shavings from rubbing parts.
The successful installation of a Chinese engine on an ant depends not so much on the power of the engine as on the quality of the transition plate and the alignment of the shafts.
Keep an eye on the engine temperature during operation, and if the cylinder head gets rainbow spots or the oil starts to burn, it means that the heat exchange is disturbed, you may need to install an additional casing to direct the air flow or clean the cooling ribs from dirt.
Frequently Asked Questions (FAQ)
Do I need to register the replacement of the engine in the traffic police?
Formally, replacing the engine with a similar power and type does not require changes in the PTS if the new engine number is read and not listed in the theft. However, if you have significantly changed the design (for example, a change in the type of fuel or drastically changed power), technically this requires certification. ants With or without tractor numbers, this is often left on the owner’s conscience, but legal risk persists.
What is the life of a Chinese engine on a cargo scooter?
With timely oil change (every 20-30 hours in severe conditions) and cleaning the air filter, the life of 1000-1500 hours before the first bulkhead. This is 2-3 times more than the native two-stroke engine. tulaIt depends on the quality of the assembly of a particular instance.
Can I use a scooter variator instead of a native gearbox?
Yes, it's a popular tuning option, and the CVT provides smooth running and no need to shift gears, but it's less tractive on steep full-load climbs than a gearbox. Ant.For heavy loads, it is better to keep the native box.
Why does the engine stop at the corners?
It's likely that the oil level sensor is activated or there's a fuel starvation due to the gas leaking in the tank. Check the lubrication system and maybe install partitions in the tank or use a larger tank with a intake in the center.
Where can I get the transition plate drawings?
There are no universal drawings, as the frames ants The stove is customized by fitting, and you can find photo reports on the motorcycle forums that will form the basis for your measurements.