How to Lubricate the Top Trimmer Reducer

How to Lubricate the Top Trimmer Reducer

Sometimes, in the midst of intense grass mowing operations, your trimmer begins to make unpleasant, grinding sounds. This complains about the lack of lubrication of the gearbox. the most intensively loaded unit of the device. And soon, these “warnings” may be followed by jamming of the drive.

What grease should be used for the trimmer gearbox?

In the process, the mechanical part of the trimmer is loaded with contact forces on the teeth, resistance reactions from adhering grass (sometimes with dirt), dynamic, impact loads due to constantly changing torque. The grease for the trimmer gear must fully take into account these features, so the selection of the brand must be strictly individual.

The following factors are taken into account:

  1. Brand of the manufacturer. Each brand is not unreasonably oriented on lubricants of its own manufacture (you can talk about cheap Chinese products later). This applies to manufacturers such as Husqvarna, Stihl, Huter, Makita, etc. The exception is domestic trimmers: for example, Caliber in the user manual does not indicate the brand of lubricant at all.
  2. The viscosity of the lubricant. As you know, all lubricating compounds are divided into three groups. highly viscous (colloidal systems containing various additives), plastic compounds of universal use and solid lubricants that soften during operation.
  3. Good adhesion to the surface of the gearbox parts, as a result of which the grease is not squeezed out into the gaps or out of the assembly.
  4. Gearbox lubricant consumption rate. Here you have to rely on your own experience and the recommendations of specialists, since some trimmer manufacturers, relying on the availability of their own service centers, generally do not give clear recommendations regarding the period of operation of the gearbox between two lubrications.

The lubricant consumption also depends on the temperature at which it retains its lubricity. When the gearbox is heated to 40 ° C, it is considered that its operating conditions are satisfactory, and there is enough lubrication.

It is believed that there is no universal lubricant for the trimmer gear, but this is not entirely true. In fact, a suitable lubricant will be one in which the following components are present:

  • Anti-wear additives containing no toxic lead;
  • Solid lubricants with the presence of graphite or molybdenum disulfide (the latter is preferable, since the lubricity is fully preserved for a wide range of shaft revolutions);
  • Only mineral (inorganic!) Oils with a high degree of purification.

These requirements are fully met by Gear Grease OREGON or Champion EP-0 lithium greases, domestic compositions Oleo-Mas, Litol.24, or Azmol 158, as well as those recommended by the manufacturer of a particular trimmer model.

How to lubricate the trimmer gear?

In the upper part of the housing, where the gear block is installed, there is a technological hole, which, when the trimmer is operated, is plugged with a screw. This screw is unscrewed, and 1.5. 2 ml of grease is introduced into the hole using the nozzle on the tube. If the lubricant was purchased in a different packaging, then for this operation, a regular disposable medical syringe is also suitable.

After that, the screw is installed in its original place. This procedure, regardless of the user’s recommendations, should be performed every 10. 15 hours of operation of the trimmer in operating mode. Other reasons for updating or replacing the gearbox lubricant are independent minor maintenance work (for example, cleaning and washing the gearbox gear before the summer season), repair of the unit, preservation of the trimmer for the winter period, etc.

If the gear unit is disassembled, it is recommended to completely remove the remains of the previous grease from the surface of the parts, even if it does not have any signs of oxidation and contamination. And only then apply new grease. After applying the lubricant, it is recommended to turn the shaft manually several times, and make sure that the lubricant is evenly distributed over all parts of the gearbox.

Video: How to Lubricate the Top Trimmer Reducer


When lubricating, special attention is paid to the following elements:

  1. Flywheel: on its surface, as a rule, the remnants of grass adhere intensively, and thickened grass juice creates additional resistance.
  2. The starter coil dog, which is constantly in contact with the grooves on the flywheel when the drive is turned on. In this case, not only mechanical wear occurs, but also mechanochemical corrosion of the flywheel-dog joint, since the materials for this pair are different (the flywheel is aluminum and the dog is steel).
  3. Bearings, if their seals are worn, and through them the grease is squeezed out. In this case, the unit begins to vibrate intensively when loaded. This happens with Chinese-made trimmers, so it’s worthwhile in the future to think about replacing the bearing assembly with a better one, for example, from the Swedish company SKF.
  1. Lower and upper gear lubrication
  2. Grease for gas trimmer
  3. Prevention and possible malfunctions of the gearbox

A responsible approach to maintenance is the key to a long tool life. One of the requirements of the lawn mowing operation is timely lubrication of the gearbox, as well as filter cleaning. What composition to lubricate the gearbox, every user of such a unit knows. First cleaned in several stages, then remove the element from the casing. It is cleaned with gasoline, dried. A place for the filter is prepared carefully, cleaning it from dust and old oil. The main signal for lubricating the lawn mowing gear is extraneous noise and fast heating of the equipment. This suggests that it is necessary to lubricate the spare part as quickly as possible. The lubrication intervals are indicated in the lawn mowing instructions. Experts say that gearboxes need to be serviced every 15 hours.

Lower and upper gear lubrication

There are tips that recommend lubrication at the end of the season. However, most people find it best to do this at the beginning of each season. When we repair the unit, as well as carry out any disassembly, it is necessary to use lubricants. The gearbox must be additionally lubricated when the old trimmer is inserted.

Modern trimmers are equipped with a gearbox that measures the angle of transmission of mechanical energy between two components: a shaft and a head. Bevel gears are considered common, they easily withstand high speed, are equipped with smooth gearing, as well as an increased level of bearing capacity. The body includes a shaft, a gear wheel, which is pressed onto the driven shaft. In order to reduce friction, bearings are mounted on the shaft support points.

Grease for gas trimmer

Properly selected lawn care gives a guarantee of durability and high-quality equipment. Manufacturers try to take into account all the nuances and prescribe what materials to use for maintenance. Usually, the specific type of lubricant is not indicated, just well-known standards are given that lubricants must meet.

The lubricant must be selected in such a way as to take into account the temperature regime, rotation speed, load dynamics and vibration. The main requirement is that this mixture remains in the zone of maximum friction.

Based on the above information, it should be noted that lawn mowers manufacturers are developing universal additional tools for their equipment. It can be served by general industrial compounds. The main condition is compliance with the operating conditions, namely, the presence of a substance against rust and lime, as well as a filler, which consists of a solid lubricant. Grease is poured into the gearbox in a special hole, the assembly is not dismantled.

Replacement is quick enough.

  1. First, turn off the device from the network. Petrol devices must be drained from gasoline.
  2. If the lubricant changes completely, then be sure to flush the gearbox. To do this, first fill in the cleaner, then rinse the gearbox well, then drain. It is important to clean the case completely.
  3. The special tool that comes with the trimmer must unscrew the gearbox plug.
  4. We apply a new lubricant: we insert a syringe with a tube into the hole and squeeze out the lubricant (2-5 ml).
  5. Manually rotate the shaft, turn on the braid at low speed without load. This is necessary so that the lubricant is qualitatively distributed in places subject to maximum friction.

Prevention and possible malfunctions of the gearbox

lawn mowing requires the first preventive maintenance immediately after the acquisition, because the manufacturer puts a small amount of grease. If the trimmer performs a small amount of work, then grease the device at the beginning and at the end of the season. If the lawn mower works a lot, then lubricate after 30-55 hours of operation.

The main malfunctions include the most common options.

  • Strong heat. This indicates that the grease has run out. It is necessary to add lubricants and run them in a weak mode.
  • The gearbox vibrates or staggers. This situation indicates mechanical damage.
  • There is a knock. Then the bearing collapsed, the boot is damaged.
  • If the trimmer knife is stuck, then the mechanism should be changed completely.

How to properly lubricate the lawn mowing gearbox, see below.