A chainsaw is a powerful tool with which you need to not only work properly, but also look after it. Only in this way can any instrument serve faithfully. Often sawyers are faced with a starter failure situation, so there are difficulties in starting the engine. To start the engine, you will need to repair the chainsaw starter. And you can do the repair yourself, taking only time to read the instructions.
Chainsaw starter. design and principle of operation
Although chainsaws have different names, they are structurally similar. The triggers of gasoline units, with which the engine starts, are similar. Mechanisms for starting ICEs are suitable for chainsaws of various brands Stihl, Husqvarna, Dolmar, Makita and others. Structurally, the starter for a chainsaw consists of the following elements:
- The drum on which the cable is wound
- Cable with which the tool crankshaft is driven
- Handle for ease of use
- The frame with a spring, thanks to which the cable is wound on the drum (returns to its original position) when the saw cutter starts the engine
The principle of operation of such a device is simple. With a sharp rise in the handle of the mechanism, the cable is pulled out. The cable engages with a ratchet, transmitting movement to the drum with splines. So there is a movement of the crankshaft, which makes several revolutions. At this point, the working mixture is compressed in the cylinder. As soon as the handle returns to its original position, the ratchet and splines connection is disconnected and the shaft stops rotating.
With each subsequent jerk of the cable, the amount of fuel-air mixture in the cylinder increases. In order for the cable to return to its original position, return springs are used in the design of the trigger mechanism. They are made of elastic steels. It is this spring that often causes a malfunction of the unit starter, which can be repaired.
Starter breakdowns and solutions
If you often have to start the chainsaw motor, this entails the accelerated development of a starting device. It is impossible to predict which part of the starting device will malfunction first, but most often the cable breaks or the spring breaks. It is not difficult to determine the malfunction of a cable break, but in any case, if a breakdown occurs, then you will need revision and repair of the chainsaw starters.
Video: How To Repair A Starter On A Stihl Trimmer
Common breakdowns of the starting mechanism of the units and their elimination:
- Breakage of the cord and its replacement. As soon as the motor starts, the cable contacts the mechanism body in the form of friction, thereby grinding it. If the cable has obvious signs of wear, it is better not to wait until the handle comes off at all, and you can start the chainsaw only after repair. The launch rope needs to be replaced, for which the case is disassembled, and the ratchet mechanism is lifted. It must be lifted carefully to prevent the return spring from slipping. The old cable is disconnected, and a new starter cord is installed in its place. After replacement, the cover is replaced
- Replacing the starter spring for chainsaws. Now we will consider how to replace the spring of the starting device of a gas unit. this is a device that returns the drum with the cable to its original position. If the spring is damaged at the point of connection to the drum (where the loop is formed), then changing it to a new one is not necessary. To do this, you can make a new loop, having previously cleaned the place of damage. After that, the spring glows to a temperature of 600-650 degrees (when it becomes a crimson color), and gradually cools. At a temperature of 150 degrees, you should bend and completely cool the part. Now you can install it in place, and continue operation. If there are difficulties with heating or the spring bursts in another place, then it should be replaced
- Do-it-yourself repair and replacement of the flywheel dogs is not particularly difficult. Work begins with dismantling the flywheel and removing the dogs. In place of the seized dogs, new ones from the same materials should be installed. If instead of plastic, you decided to put metal, then they may last longer, but the flywheel will wear out faster. How to replace the chainsaw flywheel dogs is described in detail in the video.
How to replace a starter spring on a chainsaw
If the starter spring for the chainsaw has broken, which is often found on units of Chinese origin, then you need to replace it. It is not necessary to completely change the entire starter.
Here is a detailed instruction on replacing the trigger spring:
- Initially removed the clip (drum) of the mechanism
- There is a spring in the drum structure that needs to be removed. Fasten its upper part, and pull the handle
- Replace the old spring with a new one. Before installing the part, clean the drum housing
- The new spring is initially placed in the drum, and after that it is required to get into the groove with a mustache
- The drum is put in place and the starter cover is mounted on the tool
A detailed and visual description of the replacement spring of the starter device is shown in the video.
To repair the starter on a chainsaw, you will need to find out the cause, and already depending on the breakdown, eliminate it. If the mechanism cover itself bursts, it is easier to completely replace the device. To extend the life of the trigger, you need to carry out preventive maintenance tool.