How to Repair a Starter on a Trimmer
One of the key components of lawn mowing is a starter designed to simplify starting the engine of the device. Like other parts, it breaks periodically. In this case, there are two solutions to the problem: repair of the trimmer starter or its complete replacement. The second option is simpler but more expensive. In addition, the required part must first be found on sale, as different starters are used for different models of lawn mowers. If you have free time and a screwdriver with a suitable tip, you can restore the functionality of this unit yourself if you know how it works, what malfunctions are typical for it, and how to fix them correctly. About all this. In this material.
Trimmer starter. Device and principle of operation
In order to repair the lawn mowing starter on your own, you need to understand the principle of its operation and know its structure. Today, manual and automatic starters are installed on trimmers, while the first are most often found.
The part is a plastic case in which a pulley with a cord wound around it is placed to start the engine. In order for the cord to twist on its own after the tool is wound, a belt spring made of alloy steel is located on the inside of the pulley. A ratchet is installed on the front of the pulley, which engages the starter with the drive shaft of the tool engine.
On a note! Depending on the model and brand that produced the trimmer (Huter, Husqvarna and other brands), the ratchet pulley can be a single unit or two separate components.
The principle of operation of a manual starter is the same on lawn mowers of Chinese, European and domestic production, whether it be Hitachi, Patriot or another manufacturer. To start the engine, the owner of the device jerks the cord sharply. From this movement, the pulley rotates, and the protrusions located on it engage with the dogs located on the flywheel. Next, the flywheel and crankshaft begin to rotate with a pulley. After starting the engine under the influence of centrifugal force, the protrusions and dogs diverge in different directions. And the starter cord, after the user releases it, is wound on the pulley with the help of a return spring.
Important! With intensive use, the drive cord breaks over time, and the tape spring wears out. These parts are easy to replace with your own hands.
Signs and causes of failure of the starter mechanism
There are two faults in the starter mechanism.
- Breakage of cord. With regular operation of the lawn mowers, this element is frayed and torn, which will be easily noticed by the user when trying to start a trimmer. To correct the situation, you need to replace the cord.
- Depreciation of the spring and subsequent breakage or exit of the hook from the groove. You can determine the malfunction by a cord that does not return and does not wrap around the pulley after starting the engine. To repair the trimmer in this case, just install a new spring.
In rare situations, the starter mechanism breaks when the tool is inaccurate. The consequences can be unpleasant: a deformed cord wraps around the flywheel of a running engine, the pulley breaks, and the spring bursts. But these are isolated cases, a complete replacement of the starter is very rarely required.
Diagnostics and troubleshooting
To diagnose the starter mechanism with a view to its subsequent repair, the assembly must be disassembled. It is not difficult to do this, you only need a screwdriver. But during the execution of this operation you need to be careful. With careless movements the spring may fly out and cause injury to the user.
Removing and disassembling the assembly
The procedure for disassembling the starter is to perform a certain sequence of actions:
- First you need to find the screw connecting the starter cover to the pulley and unscrew it;
- Then you need to remove the spring, antennae and washers;
- Then carefully remove the pulley, keeping the structure away from the face so that a spring that accidentally bounces does not injure the user;
- Next, you need to inspect the spring: if it is damaged, then you need to put a new one (the cost of such a part is low), but if it jumped out of the hook, you need to return it to its original place, after making bends if they break.
Winding a spring is not an easy procedure. Not everyone can get a part in place the first time, so you should not be upset if you fail. Attempts must be repeated until actions are successful. If you wish, you can watch a on the Internet, where craftsmen tell in detail and show how to easily and quickly perform this operation.
Important! When winding and installing the spring, you need to remember that it is hot, which means it can burst if you put too much effort. A new part is inexpensive, but you will have to spend time searching for it, which means that the work on mowing the grass will move indefinitely.
To wind the spring, you need to place the bend in the groove, and then, turning the coil, carefully lay the part along the inner diameter of the bobbin. In this case, the spring must be constantly held by hands. If it is not fixed, the part slides and pops out, then the winding must be performed again. When everything is done correctly, the spring holds tightly in its seat.
To replace an element, in the coil you need to find a hole for it, through which the cord is passed, and then tie a knot. Next, you will need to cock the coil with the spring, performing several revolutions.
On a note! The exact number of turns can be found by looking at the instructions for using the trimmer, or manually. To do this, measure the length of the rope and calculate how many times it can be wrapped around the coil.
For example, if the cord rotates around a circle six times, then to tension the spring, you need to rotate the coil six times counterclockwise. After that, it remains only to pass the rope through the hole and fix the handle on the cord.
Sometimes after the repair, the spring still flies. There are two solutions to this problem:
- To bend the spring does not pop out of the groove, you need to insert a small fragment of a metal plate between the bend and the wall of the seat. This will provide a more tight fixation of the spring.
- Keeping the spring in the groove also helps with homemade fastening. It is necessary to drill holes in the coil on each side of the groove, place a spring bend in them and fix it with a piece of wire. These steps should be performed so that the wire does not touch the starter cover and does not slow down the movement of the pulley.
Assembly and installation in place of starter
To assemble the starter and set it to its original place, you must:
- Turn the pulley with the spring down and place it inside the case so that the spring bend hits exactly in the groove of the case;
- Install the washer, then the spring, on top of it. The second washer;
- Place a cup with antennae on top of the washer and screw in the screw.
When assembling, be sure to put both washers, otherwise the plastic cup will be damaged by the spring after some time, and when pulling the cord, the user will notice that it is jammed. It will look like a spring has flown. To fix such a breakdown, you will need to install a larger screw or another washer. If it is not possible to find the required parts, just loosen the screw a little, after which the starter will stop jamming. However, you need to understand that these are temporary measures, and the malfunction should be repaired as soon as possible.
Sooner or later, problems with the starter arise on any trimmer. Stihl FS 55, MTD 790 or another brand. You can delay the occurrence of such a malfunction, but for this you need to carefully handle the tool. In particular, you should not make too sharp jerks, this will lead to a break in the cord or to a spring out. It is not recommended to subject the lawnmow to shock or other physical impact. If the starter housing breaks and the cord breaks, it can be wound around the engine flywheel. This will result in a ripped pulley and a bursting spring.
So, having discovered that the starter mechanism has broken on the lawn mowing, one should not immediately rush to the specialists for help. Knowing how the malfunction is eliminated and / or the part is replaced, repair work can be performed independently. No specific tool is required for this. At first, the procedure may seem complicated and tedious, but numerouss on the Internet dedicated to repairing the starter can help solve the problem as quickly and easily as possible.