Not included back gear on the power tiller
Kentavr brand motor blocks and cultivators have long been very popular among Ukrainian farmers. The single-axle tractor Kentavr 2090d is a fairly powerful universal agricultural machine, equipped with a manufacturer of engines in 9 liters.с. This model is one of the most popular and owners of medium and large plots.
In case of malfunction in the work of your machine, do not panic and immediately spend a lot of money on a professional and expensive repair. Sometimes it is enough to identify the problem and replace the failed part. It is important to understand that any technique can break, the components fail due to wear and tear and need to be replaced. The online store Agrozip offers its customers to buy spare parts for the Kentavr 2090d/2091d power tillers at the lowest prices.
How and why the noise of “mechanics”: secrets of gearbox noises
Mechanical car transmissions often scare the drivers with different sounds, which from time to time are heard from the bowels of an inherently simple device. As a rule, the motorists themselves are to blame for their occurrence. But there are also sounds that appear for reasons beyond their control. Let’s find out why the gearbox “sings” and is it worth to be afraid of.
Before we get into the nature of the sounds, let’s review the gearbox and explain “on our fingers.
As we know, the internal combustion engine is not able to transfer maximum torque and power to the wheels of the car from idling speed. It needs to reach the optimum speed (usually not a small one) in order to provide maximum output. This can be done by means of a gearbox, which changes the transmission ratio, thereby making life easier for the engine and endowing the vehicle with high speed.
A clutch is a device that lets you change the transmission ratio in steps. In essence, it is a metal box, inside which there are two or three parallel shafts with gears that set the speed of the secondary (driven) shaft and, accordingly, the wheels of the car. through the main gear and differential. The task of this entire structure is to transmit the torque from the engine flywheel to the wheels. Combining the gears in various combinations, we get different ratios.
Gears on the secondary shaft are movable and connected to it by couplings that act as locks. By engaging and disengaging the clutch, the driver engages and disengages one or another gear. In this case, one clutch is used for two gears. This is where one of the unpleasant noises can be heard.
That horrible grinding noise when you change up to the next gear
When shifting gears, drivers often forget to depress the clutch or don’t press the pedal all the way down. Then you hear a frightening metallic clang from the box. this noise comes from the gears, which can not get into contact with each other.
Why this happens? When we disengage one of the clutches, the secondary shaft rotates at one speed, and the gear in the next gear rotates at another. You have to synchronize the speeds of the shaft and gears in order to change gears. To do this, the engine is briefly disengaged from the transmission by depressing the clutch. When disconnecting the engine from the transmission speeds are equalized and clutch engages with pinion of the next gear. Special devices. synchronizers provide additional assistance in alignment of speeds.
They work as follows. When selecting a gear, the shift fork moves the clutch to the gear of the selected gear. The force is transferred through the knuckles to one of the locking rings, which together with the clutch moves in the direction of the pinion to be engaged. A frictional force is created on the mating surfaces, which rotates the locking ring until it reaches the stop. The speeds of the pinion and the synchronizer are aligned, the pinion is firmly connected to the shaft and the gear is engaged.
When the clutch is open, the torque from the wheels via the synchronizers accelerates the secondary shaft (when downshifting) or stops the box’s primary shaft (when upshifting). It is difficult to achieve an exact match of rotation speeds without depressing the clutch. That is why gears either don’t engage or engage with a loud unpleasant sound. The cogs do not engage correctly and touch each other with their teeth. This leads to excessive loads on the gears and can cause them to break.
Peculiarities of gearboxes on motor blocks
The gearbox is a must for any power tiller class. Even for such small-sized equipment, controlled by hands, the ability to change the speed is not a whim, but a vital need. Such transmission also has a reverse gear (reverse gear), but many manufacturers put on the market models without reverse gear. this makes the technique cheaper and safer.
There are different ways of transmitting the rotational motion of the motor crankshaft to the axle of the power tiller:
- The belt drive is considered the easiest and cheapest to produce. Such a mechanism usually consists of several pulleys joined by a belt. Repair of such a transmission is also not difficult, but the reliability of belt transmission is low. the belt over time stretches, slips, wears out and breaks. Large loads are not for it, so the belt drive is used on low-power models of small weight;
- The chain drive is a step up. It is the most widespread in power tillers: not very expensive, quite reliable, copes well with heavy loads. The chain drive is installed on mid-range motor blocks, it is also found on some heavy-duty models;
- The gearbox is considered the most reliable type for small equipment. Consists of several gears of different shapes, cylindrical or cone-shaped. Such a gearbox provides many times the number of gears. Typical for heavy power tillers. six forward and a couple of reverse. Of course, such a box is the most expensive, a breakdown usually requires replacing one or more gears.
Many manufacturers combine these methods in their products, trying to bring the advantages of some types of transmissions and get rid of the disadvantages of others into the design. Thus, quite often there are units in which the gearbox is of gear type (or chain type), and the transmission is implemented by belt drive. This method is good because under excessive loads, it is very likely that the belt will be damaged, but the gearbox will remain intact.
Quite often there is a gear-chain transmission, which has the main advantage of a decent endurance.
As for the rear gear itself, there is a completely different policy of manufacturers. Some models even have a reverse gear, others try to do without reverse gears.
In general, the logic can be traced. Small motor blocks with two-stroke engines and weighing no more than 30 kg., can be turned on the spot without much effort. So the presence of reverse gear here is a redundancy, given that such a design is more complex, it increases the weight and size of the product and creates additional difficulties in the maintenance and repair of the power tiller.
The heavy tillers designed for large areas and hard terrain are another matter. It is not easy to maneuver such a machine without rear speed, that is why such models usually have reverse. And the most popular and widespread models of the middle class. here as God wills. Even the same model in different generations may or may not have reverse gear.
It also matters what type of gearbox you have: gearboxes and chainboxes allow you to reverse when the motor is off. And if you use a worm gear, you can’t reverse without reversing, you’ll just have to pull the single axle tractor back if you need to. You’ll need a lot of strength and stamina for a 50- to 80-pound thing. Fortunately, worm gears are commonly installed on lightweight models that can easily be lifted and moved or swung around even when the motor is off or the gear is locked.
how to work back gear #powertiller #petukjamai
And yet the presence of reverse is an undeniable advantage. Its absence sharply reduces the functionality of motor-block, so many owners decide to modify the gearbox with the sole purpose. to ensure reversible motion of motor equipment.
Safety locking of the reverse lever
Provides you with a higher degree of safety when operating your power tiller. Eliminates the possibility of accidental reverse.
All air-cooled Centaur gearboxes do not have a separate reverse gear. Rear drive of these tractors is activated with a special lever on the right handlebar: you must shift to neutral gear and press this lever and at the same time the clutch lever.
New reverse lever design has a special safety feature to prevent accidental reverse. The lever can now only be depressed before depressing the safety catch. This also makes the single-axle tractor safer to operate, because a wrong choice of driving direction can lead to breakages and even injuries. New lever greatly reduces error possibility.
Shifting crunch: Where it comes from and how it can be “repaired
When comparing different types of transmissions “mechanics” usually turns out to be the most trouble-free and resourceful, but nothing is eternal. with long operation problems can begin with the manual transmission. They often start with a crunch when shifting gears. It will not immobilize your car, you can continue driving, but strange sounds should alert the driver. it is the first symptom of an impending failure of the gearbox. If the box does “crunch”, what to do?
Causes of crunch
The manual transmission unit is complex, but conservative. It almost does not use computers, sensors, complex control systems, so the main breakdowns are due to mechanical causes, most often the banal wear and tear of components.
Synchronizer breakdown. The synchronizer, remember, is a device that aligns the speed of the gears when shifting gears, which makes the speed change smoothly and easily. Earlier, before synchronizers were used in gearboxes, drivers had to overdrive, which made driving the car very difficult, today’s drivers have forgotten about it. But it helps only until the synchronizer is good, worn element can no longer synchronize the speed of shafts, so when meshing, there is a strange sound. If only one gear crunches, it is most likely because of the synchronizer.
A classic example is a transmission of front-drive Lada family. During the design engineers poorly chose the gear ratio of the second speed, so elements of this gear are experiencing increased loads. The synchronizer of the second gear is usually the first to break.
Worn shafts. Primary and secondary shafts of the box are subject to failures. teeth on gears are erased, bearings break, alignment can be disturbed. Due to the problems with the shaft, the crunch is likely to be when you engage not one gear, but several, perhaps the crunch will be in motion.
By the way, problems with the shaft can also have a temperature effect. If the gears shift normally in the cold, but after the oil warms up other sounds occur, it is the shafts which are suspected.
Not enough oil in gearbox. The cause is banal, but in practice it is not so rare. Oil may “leak” because of depressurization of the box due to mechanical damage, unintentional unscrewing of drain plugs, wear of seals or other causes. For example, in many Renault cars, the gearbox is connected to the inner joint of the left actuator, through which the oil can leak.
Breakdown of the clutch basket. Flappers of the basket may be worn out or break off during the long time of operation, and then the clutch will not fully engage, which causes the problems while engaging the gears. The box itself will not be at fault here.
Problems with the clutch actuator. Depending on the type of actuator used (cable or hydraulic), there can be a whole host of problems, from cable breakage to leaks and clogged fluid. It also has nothing to do with the gearbox, but if the clutch won’t engage properly, you can forget about soft and quiet gear shifting as well. Usually problems with the clutch affect all gears in the box, this will give reason to think in this direction.
By the way, not always a crunch when engaging a gear is a malfunction. In modern budget cars (for example, Renault Logan) often in the rear gear there is no synchronizer, so when you quickly engage the reverse gear without a complete stop the car crunch is heard. This is not a malfunction, but a characteristic feature, which cannot be “cured”. The only way to help is to change the method of gear shifting by the driver, for example, to shift into reverse with a certain delay and only when the car has come to a complete stop.
Ways to repair
Repairing the gearbox is not an easy matter, but there is not much to diagnose. If the gearbox is rustling, you should start with the easiest one. check the oil level. Every box does it differently, but the main thing is to make sure there is enough lubrication for all parts. If that was not the problem, you need to remove the box and diagnose the clutch, otherwise there is no way. If no critical problems are found here either, you will have to disassemble and defect the unit itself. The worn and damaged elements are replaced with new ones (it is good that the gearbox components are usually sold separately), and then the construction is assembled back.
No one can predict transmission failure, but often the driver provokes it by his actions, improper use of the machine. What you need to pay attention to so that the box will live longer.
Change the oil. In modern service books for almost all cars with “manual” transmission it is written that the oil in the transmission is designed for the entire life of the car. This gave rise to the opinion among drivers that only the automatic transmission needs to have the oil changed, while the “mechanics” don’t need to. But really you should. Of course, transmissions are not so critical to the lubrication purity, but with high mileage and in it develop wear products, which deteriorate the work of the box. How often should the oil be changed in mechanics is a debatable question, but the most popular recommendations rotate around the mileage of 80-100 thousand kilometers.
Select the right gear. Switching too low or too high revs is detrimental to the whole car, including the gearbox. Stresses on transmission elements increase, and their life is reduced. So, don’t shift into first gear at 60 km/h and into fifth gear at 30 km/h.
Don’t keep the clutch depressed for a long time. It would seem to be the recommendation from driving school, but as practice shows, not everybody understands the harm from it. A long squeeze is additional load on the clutch elements, the service life of which is far from being eternal.
Crunching of the box is always unpleasant. And the acoustic effect irritates, and bad thoughts. However, if the gears have already started to “shift” with an additional sound, most likely, you will have to do the repair, and it will not be the easiest and cheapest. It is better to avoid crunch and to prolong gearbox life, changing oil in proper time and treating it with care.
Why does the gearbox not work: Causes, diagnosis
The gearbox connects the rotating flywheel of the engine to the wheels, regulating the speed and power of the car. Maximum speed is allowed only at a certain speed, so the importance of timely gear shifting can hardly be overestimated. Durability and trouble-free work of an internal combustion engine depends on how the gearbox works. Another important characteristic is the gear ratio, which reaches its highest value in the lower speed ranges.
It is important to understand the principle of operation and know the structure of the manual transmission to understand the possible causes that lead to the fact that the gearbox does not work.
- three types of shafts reverse shaft, which are equipped with gears with a different number of teeth;
- synchronizers, which equalize the angular velocity of the shafts and reduce noise during operation;
- gearshift mechanism with locks and locking devices to hold the gears in the set position;
- crankcase in which bearings are mounted to facilitate the rotation of the gearbox shafts;
- gearshift lever for the driver.
All gearboxes are divided by the number of steps or gears. They come with two shafts, which are mostly installed on cars with front-wheel drive, as well as with three, consisting of a drive shaft, intermediate shaft, secondary shaft.
Speed change of a motor block Motor Sich photo video.
Gearchanges on a motor block Motor Sich photo video.
The engine block has a mechanical gearbox with three shafts and spur gears, with four forward gears and two reverse gears.
The gearbox of the motoblock is controlled by levers mounted on a special console on the steering column.
Diagram of switching gears and locking differential single axle tractor Motor Sich photo, as well as table maximum speed in all gears.
As you can see from the diagram, the left gearshift lever, has three fixed positions:
The right gearshift lever has three fixed positions:
Gears and modes in the gearbox of Moto Sich are easy to shift, without any hitches and growls, well fixed in the right positions.
The gearbox of a power tiller does not cause any special problems to the owners of the power tiller.
Oil used and recommended by the manufacturer in the gearbox motoblock motor Sich so-called TAD-17i (modern name TM-5-18) or TAP-15B, which corresponds to the type 80W90.
I personally, filled in the gearbox motor Sich, fully synthetic gear oil Castrol SYNTRANS Z LONG LIFE 75W-80 API GL-4, which immediately had a positive impact on the clarity of the clutch and transmission.
Shifting gears single axle tractor Motor Sich video.
As you can see in the video, the gears and modes on the Moto Sich power tiller are engaged easily, smoothly, without excessive noise and problems.
If you have any questions or additions, please do not hesitate to write in Комментарии и мнения владельцев.
What you need to change the cable with your hands
For the second (better method) you’ll also need
What to do if the reverse gear malfunctions? Options for manual transmission and automatic transmission
Many drivers wonder what to do if the rear gear is badly engaged. This is a very common problem. And the problem can occur in all types of manual transmissions. You need to fix this problem as soon as possible. At best, it may be just a pain in the neck, but it may also end up in a gearbox malfunction.
Such trouble can happen suddenly, and you will have to call a tow truck. When repairing be careful. The mechanism of the box is quite complicated. So if you are not confident in your abilities, it is better to entrust the work to professionals. Also, do not forget that the gearbox requires constant care, timely preventive maintenance will save you from many problems.