Defective lawnmower drive: 7 common problems with a solution

Petrol lawnmowers are powerful and their use is not tied to a cable or battery life. However, they are also very noisy and comparatively high-maintenance. Typical problems with the lawn mower drive on petrol models include:

• wear and tear
• Bowden cable is defective
• lack of fuel
• contamination and clogging
• spark plugs

wear and tear

If the lawnmower is getting old or has been used very often, wear and tear is not surprising. For laypeople, however, it is difficult to tell which components need to be replaced. In this case, the repair should be left to a specialist.

Axles and wheel bearings are an exception here. If the lawnmower is opened, a bent or broken axle will be noticed at the first visual inspection. Worn or defective wheel bearings, on the other hand, are usually indicated by the fact that initially only one wheel is stuck and others can be added. Replacing the wheel bearings and axles is more difficult, so without the appropriate experience it makes sense to entrust the repair to professionals.

Bowdenzug

In the case of petrol-powered lawn mowers, the Bowden cable is a common cause of a defective lawn mower drive or wheel drive. Especially models with inferior components often break or can come loose. Since the Bowden cable can function both as a lawnmower drive and as a brake cable, operation is always disrupted if it is defective. The advantage here is that Bowden cables can be replaced or repaired comparatively easily. If a defect is found, proceed as follows:

1. Measure the length of the Bowden cable and then remove the cable. It is usually sufficient to loosen the locking screw on the mower handle and cut off the lower end with side cutters. The Bowden cable can then simply be pulled out of the guide.
2. With the new Bowden cable, the end cap is removed and the inner tendon pulled out. The plastic tube is pulled through the eyelets.
3. The metal tendon is inserted into the plastic tube in such a way that the thickened end serves as an attachment to the lower attachment point. After the metal cord has been pulled completely through the hose, the length can be adjusted if necessary. Again, a side cutter is used for this. It should be noted that the Bowden cable must be tensioned when activated in order to trigger the drive. In addition, the metal cord must be so long that it can be easily attached to the handle of the lawnmower.
4. Pull the upper end of the Bowden cable through the intended fixing point and fasten it with a special clamp or screw, or you can make a fastening device for the wire yourself. For the self-made attachment, a screw is drilled just below the screw head. The hole should be big enough to easily thread the wire through twice.
5. The fixation is screwed tight or closed. With a screw attachment, the wire is first pulled through and then looped around the handle of the mower. After looping around the handle, the wire is pulled through the hole in the screw again and ideally knotted around it. For fixation, a nut is screwed onto the screw until the wire is clamped between it and the screw head. The screw is held with a wrench or pliers and unscrewed another screw. The two screws fasten each other and prevent them from loosening while mowing the lawn.

Lack of fuel

If the lawnmower drive seems to be defective, the first thing to do is take a look in the tank. Even if the gauge still shows a tank of fuel, some fuel can still be added. If necessary, the display can simply be defective and the tank has run empty unnoticed. In this case it is not necessary to repair the mower.

contamination and clogging

Dirt and blockages on the axles or other parts of the lawn mower can be responsible for this, especially if the wheel drive seems to falter or the wheels keep locking up. But dirt can also cause a defect in the lawnmower drive and blocking of the cutting blades.

A thorough examination and cleaning can eliminate the problem. The following steps are important for this:

1. Elevate the lawnmower or lay it on its side so that you can also see and clean the ground area.
2. First clean the outer area. This includes the wheels, the visible sections of the axles and the cutting blades.
3. The inside of the lawnmower can also be dirty or blocked by foreign bodies. Depending on the model, the base plate or the cover should therefore be removed to check the interior or engine compartment of the mower. It should be noted that water or household cleaning agents should never be used inside the mower. However, cleaning with a cloth, brush or special oils can ensure that the drive works again.

Strictly speaking, there is no defect here that needs to be repaired. However, existing damage can also be noticed during cleaning.

Defective spark plugs

A special feature of petrol lawn mowers is the spark plugs. If these are dirty or defective, the engine can no longer be started . The following instructions show how to clean and change them.

1. The engine cover is removed to reveal the spark plugs.
2. The spark plug connector is pulled off the spark plug and this is loosened with the spark plug wrench. The key is either included with the lawnmower or has to be purchased separately from a specialist dealer.
3. If you notice dirt on the spark plug or the cylinder, you should first remove it. Dirt can cause the contact to be broken and the lawn mower drive or wheel drive to stop working. Only a dry cloth should be used for cleaning. If this measure does not help, a change must be made to repair the drive.
4. In order to change the spark plugs, the exact designation must first be known. This can be found in the form of a marking at the lower end of the spark plug, below the hexagonal connection. So that the candle really fits into the lawnmower, the exact model should be bought later.
5. Insertion or replacement is carried out in exactly the opposite order to removal. The spark plug is inserted and tightened with the spark plug wrench. The spark plug connector is then put back on.

electric lawn mower

An electric lawn mower can have similar problems as a petrol-powered model. The tank, spark plugs and Bowden cable, however, are not required for electric lawn mowers. However, common or possible problems are:

• wear and tear
• blockages and dirt
• cable damage

Wear and tear and damage to the axles and wheel bearings are the same as with petrol lawn mowers. It is better to repair it in a workshop, as finding the cause requires some specialist knowledge and skill. Blockages and dirt, on the other hand, can be removed as already described.

In addition, with electrically operated lawn mowers, it is mandatory to completely disconnect them from the power supply before each inspection and cleaning. Otherwise there is a high risk of injury.

With electric lawnmowers there is always a risk of cable damage. These can be triggered by various reasons:

• clipped or cut cord by the mower blades
• insulation and wires chewed by animals
• Cable break due to incorrect winding
• Loose contacts due to unfavorable forces acting on cables or connections

Damage to the cable is the same as wear and tear. Repairs should be carried out by appropriately qualified personnel. On the one hand, because tampering with the power cable poses a high risk potential. On the other hand, because finding and fixing the problem requires specialist knowledge.

Battery lawn mower

Wear and tear, blockages and dirt can also occur with cordless lawn mowers. As with petrol and electric lawnmowers, you can do the cleaning yourself. Replacing axles, wheel bearings and the like, on the other hand, is more difficult.

Unlike other drive types, however, a defective battery can be the cause of the problem with the cordless lawn mower. If the lawnmower drive or wheel drive fails, you should therefore first check the battery. On the one hand, this can be done when loading. If the charging times suddenly deviate or the indicator lights indicate an allegedly incorrect charge level, you can test a new battery.

Another way to check is to insert the battery into another garden tool. If there is another device of the same brand in your own household, with friends or neighbors, the problem can be very easily isolated in this way. If the battery works in other devices, there is a different problem with the lawn mower.