The single–axle tractor Neva MB 1 is arranged according to the classical scheme and includes the following elements:
- power unit;
- clutch device;
- fuel tank;
- control system.
The “MB1” unit has 4 gears. 3 for forward travel and 1 for reverse. Thanks to the fact that there is a possibility of changing the position of the belt on the pulley, you can realize an additional set of gears. Thus, it is possible to substantially increase the volume and quality of work performed due to the flexible choice of speed modes. The “MB1FS” modification has an electric starter, which is powered from the generator and battery, which significantly simplifies the process of starting the engine and makes it possible to use the headlights at night. In order to start the unit, now it is not required to apply any physical effort and pull the cord, but it is enough to use the ignition key, as evidenced by the instruction manual for the Neva MB power tiller.
The main problem of using power tillers Neva
A large amount of tar, dirt and water in the domestic fuel during operation kills imported engines completely. Therefore, the owners use a method that is not in any instruction manual fill imported gasoline, preferably Finnish, or use a fuel purification slot charcoal filters under pressure.
In this case, the service life of a motoblock with a Subar motor will easily exceed the estimated 10 years, and the Neva, complete with Briggs Stratton, can go out on good engine oil and correct operation all 15-20 years without an overhaul of the engine.
The operation of a power tiller is, in fact, the most unfavorable for any engine, but the Kaluga DM-2 engines burn for some reason. These engines are designed for the most average quality fuel and oil, the most ruthless operation, so the developers have equipped this version with a cylindrical version of the block, assuming an increase in total life to 10 years.
According to the instructions, the owner can replace or repair the liners. But in practice, craftsmen say that problems with operation and overheating of the DM-2 arise precisely because of the low rigidity of the liner and poor heat dissipation.
Setting the clearances
Adjusting the motor valves means setting the optimum clearances. Their norm is specified in the technical passport of the motoblock. Each model has its own allowable parameters, which depend on the brand and type of motor of the machine.
The permissible valve clearance on the motoblock for a standard unit has this value:
You will need the following tools to adjust them:
The algorithm for setting the optimum clearances is as follows:
- The engine must be cool during the operation.
- Disconnect the cup with oil bath from the air filter and the filter element.
- Take a wrench, unscrew the 4 bolts around the guard.
- Remove the starter motor, then the flywheel guard.
- On the end of the flywheel fix the “dead point”. The mark on the rib of the blowing cylinder must correspond to the zero mark of the flywheel.
- Carefully remove the valve cover with a paronite gasket, having previously unscrewed 3 bolts.
- Check the clearances:
- near the filter is the inlet valve;
- near the muffler is an outlet.
Insert dipstick between rocker arm and valve to check interval. If the distance is greater or less than allowed, use a socket wrench and screwdriver to adjust the elements.
- Wipe all mechanism connections with a clean rag.
- Reassemble in reverse order.
- Turn on the single–axle tractor, check its performance.
If the valves are properly adjusted, the engine will run without noise, jerking or malfunctions.
Operation and maintenance of the Neva MB-2
Replacing gear oil seals
Oil seals in the Neva MB-2 power tiller should be changed when oil leakage is detected.
A similar condition is not safe because the motoblock gearbox can be left without oil, and this will lead to a sharp wear of the unit.
Seal replacement sequence is as follows:
- Remove the cutters from the shaft, cleaning the shaft and covers of dirt and oil residue.
- Unscrew the bolts of the cover, knocking off the oil and debris, and remove the cover from the gearbox.
- The old packing is replaced with a new one, wiped dry.
- The cover is put back in place (if necessary, it is put on the sealant) and secured with bolts.
How do you start up power tillers??
As you know, power tillers can be gasoline or diesel. The start up is done in different ways. Therefore, the reasons why the single–axle tractor Neva does not start may vary greatly.
Before you start a single–axle tractor after purchase or after winter, you should check the presence of each part and their condition, the condition of contacts and wires. It is also necessary to change the oil and refill the fuel.
Most often, the unit may not start just after winter. You must remember that storage in a cold and damp room does not go away. You will encounter problems such as:
Always check the oil level before you start. If it is not enough, the piston group can fail completely.
Repair of the power tiller Neva: how to do it right without the help of specialists
At first it is necessary to notice that among many models of the specified manufacturer, exactly MB1 and MB2 are considered the most known and widespread. On their example, and we will deal with common malfunctions.
- If the owner of the motoblock noticed an oil leak on the output shaft, he should immediately remove the half axle caps and replace the collar;
- If there is a jamming of the gearbox, it is necessary to disassemble the mechanism and replace the unsuitable chain;
- If there is no kinematic connection in the gearbox, it is necessary not to delay and renew the sprocket in the block;
- Problems with the gears can appear as a result of the destruction of the shift knob or because of the sheared threaded portion of the shift knob. To get rid of problems, it is worth replacing the damaged parts;
- When the overrunning clutch begins to malfunction, it becomes obvious. Remove the starter, take out the clutch and grind grooves for balls. Filling up with a little quality oil minimizes friction between the clutch and the shaft.
The cause of repair of the Neva MB-2 motoblock can be:
- Valve belt not correctly adjusted;
- Gearbox oil seals;
- Incorrect carburettor system setting;
- ignition not aligned;
- spark plug malfunctions.
Мотоблок Нева МБ-2. Правильный запуск и глушение двигателя.
Belt adjustment and sizing
The V-belt on a power tiller helps the machine move forward and backward. When the timing belt comes off, the machine does not work right.
In order to determine the size of this part, you must measure the gap from the pulley to the rollers. Recommended belt dimensions: width. 0.85 cm, height. 0.6 cm.
Инструкция по сборке и запуску мотоблока НЕВА
To tension the belt, you need to do the following manipulations:
- Remove the casing.
- Loosen the tension screw of the standard belt part.
- Remove all the screws that hold the bracket to the body of the power tiller.
- Pull out the old part and make pulley adjustments.
- Wipe out the area between the parts and blow out the rods.
- Install a new belt, one end of which should be connected to the shaft and the other end to the pulley.
Replacing the gearbox oil seals
Improperly functioning oil seals could be the cause of gearbox failure. Therefore, the repair of the gearbox of the Neva motoblock may include the following actions:
- Disassemble the cutters from the shaft part.
- Clean off dirt and oil residue from the shaft and cover. Remove all screws from the cover and wash them.
- Replace the old part with a new one and wipe the whole mechanism dry.
- Put the cover back in place and fix it with bolts.
In some cases it is necessary to disassemble the gearbox:
- Remove the head from the shift knob.
- Remove the bushing and spring from the shaft.
- Remove all screws and bolts.
- Using a thin screwdriver or a knife remove the right side of this part.
- The removed parts should be washed and the defective parts should be replaced.
- Reassemble the gearbox in reverse order.
Мотоблок НЕВА МБ 2 // Полезные советы
Adjustment of clutch belt on “Neva MB 2″ power tiller
Belt comes off the pulley, slippage, replacement after a breakage. The instruction prescribes the dismantling of the expansion roller. Possible option:
- Loosen the bolt fastening of the engine to the frame.
- Pull the motor towards you. tensioning, reverse movement. loosening.
- Pressing to assess the deflection. Optimal. 10 mm.
Belt tensioning of “Neva MB-2″ power tiller