How To Sharpen A Knife From Bosch Lawn Mowers

How To Sharpen A Knife From Bosch Lawn Mowers

DIY lawnmower repair

A lawn mower is a wonderful alternative to a manual scythe, which facilitates and accelerates the mowing of grass in a variety of places, including those where an ordinary scythe simply does not turn around. But behind the comfort and convenience is a sophisticated modern mechanism that requires constant attention and regular maintenance.

Regardless of the manufacturer, all units have a similar design. Therefore, repairing a Viking do-it-yourself mower is done similarly to repairing other brands: Husqvarna, Calm, Bosch, Gardena, Oleo-Mac. A self-made lawn mower will not be an exception, but repairing a breakdown requires basic knowledge. Consider the most common causes of engine failure, and do-it-yourself lawn mower repair in the field.

Types of Lawn Mowers

The traditional "pusher" technique has long received knife drives from electric motors, which greatly facilitated the process. This type is still very popular, especially among those who want to get a beautiful lawn, but nothing compares with the relative novelty of the domestic market. rotary mowers that easily cut even the tallest grass.

Rotary type mowers are powered only from mains, and cylindrical mowers. both from the mains and from the batteries.

Both types are represented by different modifications. Gas mowers will not be considered separately, but the proposed options for eliminating breakdowns are identical in most cases. You should always have an operating manual on hand or seek advice from professionals if problems arise in the care or use.

Cylinder mowers

They include spiral knives, the combination of which resembles a cylinder. A large toothed pulley located at one end drives the belt (in some cases, a chain), on the other hand, is worn on a second, small pulley attached to the motor shaft. The engine can also set in motion a skating rink that moves equipment on the ground.

Composed of the following elements:

  1. Switch lever.
  2. Emergency shutdown and safety lock button.
  3. Switch.
  4. Filter.
  5. Air intake grille.
  6. Knife clearance adjuster.
  7. Fixed knife.
  8. Knife cylinder.
  9. Large toothed pulley.
  10. Drive belt.
  11. Drive pulley.
  12. Height adjusting lever.
  13. Electric motor
  14. Ice rink.
  15. Power cable.

When the cylinder rotates, the knives press the grass to a fixed knife attached under the cylinder, thereby creating a cutting effect that resembles the principle of operation of scissors. Any damage, even the slightest, wear, improper fastening of the knives makes the operation of the equipment less efficient. The grass cutting height changes after adjusting the position of the roller or wheels located in the front or rear of the knife cylinder.

Rotary mowers

They have one knife horizontally fixed to the motor shaft. Rotations at high speed make it possible to cut off both grass and other plants. Some models have rims with replaceable plastic knives. they are easy to replace if necessary.

Individual mowers have wheels, but most models move on air cushions. Here, the engine rotates the impeller, which distills the air masses under the hood. creating a lifting force. A metal knife is placed under the impeller.

Rotary type mower made up of:

  1. Lever switch.
  2. Emergency stop and lock buttons.
  3. Circuit breaker.
  4. Electric motor.
  5. Bonnet.
  6. Drive shaft (engine).
  7. Housings.
  8. Impellers.
  9. Clamping nut of the knife.
  10. The knife.
  11. Distance washer.
  12. Air intake grille.
  13. Power cord.

If we talk about mowers on airbags, in them distance washers are installed above the knife, regulating the height of mowing grass.

Video: How To Sharpen A Knife From Bosch Lawn Mowers


As an alternative, you can simply flip the blade with plastic knives to increase or decrease the cutting height.

In all types of equipment there may be containers for collecting grass scraps.

Some gardeners prefer one that cuts the grass as finely as possible and leaves the trim on the lawn as mulch.

The value of emergency switches

All modern lawn mowers have security systems that will not allow you to start work if both handles are not simultaneously involved or the combination of the shutdown lever with a safety lock button. The switch trips as soon as the lever is lowered.

When working with electrical engineering, you must take care of your own safety. Refuse to use equipment if you are very tired and cannot be attentive. Before plugging in the power outlet, check the condition of the power cord, make sure that all protective devices, knives and fasteners are securely locked. Unwind the cord completely, put the excess near you along the edge of the lawn from which you will start.

Before work, check to see if there are any small objects (pebbles, bones) on the green area that could ruin the knives or be thrown back by the same knives with great force. Hold the cord on your shoulder, grab the handle with both hands. In the process, make sure that the cord is always behind. Before adjusting the cutting height, the equipment must be disconnected from the mains.

After completing work, pull the plug from the outlet, remove the rest of the grass from the knives and the air intake grille. Wipe the case with a dry cloth. With a plastic or wood spatula, remove the mulch from the bottom of the mower near the air cushion. At the end of the season, thoroughly clean the lawnmower again, rub the knife with an oil rag. Remember to grease bearings and adjusters. Also check the condition of the power cord: if it is badly worn, order a replacement to be ready for the start of next season.

Device

All electric lawn mowers are designed the same way. They have a platform for mounting a motor whose shaft is parallel to the ground. A knife (or two) is fixed to the shaft of the electrical device, with which weeds are mowed. For mowing to be of high quality, the speed of the cutting electric tool must be high.

For convenience, the platform itself is equipped with four wheels and a handle with engine control elements fixed to it. It is designed to push the device forward and control the electric mower.

Wheel mounting can be rigid and swivel. In the first case, you will have to lift two wheels on turns. Swivels involve the use of less physical force.

In addition, they “spoil” the lawn less. Therefore, if flowers are planted on a lawn, there are swings, arbors, etc., then it is recommended to use swivel wheels. Electric lawn mowers with such wheels are convenient for caring for areas under shrubs and trees.

The engine is enclosed by a housing that at the same time protects an operator working with an electric lawn mower from accidental injuries. The material used for its manufacture is more often plastic and less commonly metal. As you can see, the electric lawnmower device is quite simple.

The most common breakdowns

Any technique sooner or later fails. It is important to know how you can repair mowers, because far from all cases you need to contact a service center.

Mower does not cut grass

In most cases, dull or severely damaged knives become the cause.. To achieve the best results, just change the knife every year. Choose a knife that suits your model. When the knife is dull, you can grind it using an electric grinder or a file. When sharpening, be sure to use safety glasses and gloves. The sharpening angle on both sides is approximately 30 degrees.

In cylindrical mowers, the clearance between the knife and cylinder should be less than the thickness of the paper. Some of the most modern models have built-in knurled controls. In other cases, you will have to use keys and screwdrivers to make the necessary adjustments. Make sure the clearance is even along the entire length of the cylinder. To check the adjustment, insert a sheet of paper between the cylinder and the knife, slowly rotating the drum by hand. Gradually adjust on both sides until the paper begins to cut cleanly at every point on the fixed knife.

The mower is difficult to move

  • When the mower is difficult to move around the lawn, you may be trying to remove too high grass and you will have to adjust the mowing level. When jamming rollers or wheels, they need to be inspected to make sure that there are no clippings of grass and debris. Most likely, they must be removed and cleaned.
  • If interference with air intake has formed, the lift will decrease on the mower’s air cushion and make it difficult to move. Lack of air causes the engine to overheat. Turn off the power and remove any remaining grass from the intake grilles.

The technique does not turn on at all

Long and wet grass can easily block knives. Remove the plug from the power supply and use a wooden object to rotate the cylinder to the other side of the knife until the movement becomes free. For gas mowers this technique cannot be used.

The belt for the operation of cylindrical lawn mowers wears out, stretches and may break. Remove the belt cover and check if there is a break or the belt just pops off. Loosen the fastening screws and slide the small drive pulley to the large cylinder pulley. Put the new belt on the small pulley and slowly rotate the large one, gradually putting the belt on it. Move the pulley to the side to tighten the belt, then tighten the screws.

Before installing the cover, be sure to check the belt tension. the degree of deflection should not exceed 4 mm (the indicator may fluctuate slightly depending on the model, detailed information is contained in the user manual).

Break in the cord

Each time you use, you unwrap, move and fold the cord. This can lead to a break in the internal conductors. On many models, the cord connects to the screw terminals, which makes it possible to quickly check and replace it. If double insulated, connect a two-core cord.

Other models use clamping contacts to facilitate replacement. Turn off the power, separate the plastic cover. When unscrewing the clamping strip, pay attention to the connection of the cord to the switch to observe the polarity of the connection (color of wires).

To disconnect the cord, insert a hex wrench into each of the holes in which the conductors are located. to release the clamp and conductor. Check where the gap has formed.

If necessary, connect a new cord: twist together all the individual wiring of each core, then insert the twisted ends into the appropriate terminals. Pull lightly to check connection. Then reinstall the clamping plate, cord sleeve and switch cover.