How to check the spark plug on the trimmer

Lawn trimmer does not start? Adjust the clearance on the magneto

If the grass trimmer or lawnmower does not start, then any desire to mow the grass is gone. Very often the owners of these tools face difficulties starting a two- or four-stroke engine after winter, when the tool has not been exploited for a long time. If such a situation has occurred, you should not rush to surrender the tool for repair. Start troubleshooting from less to more, and you’ll have a 100% chance of getting the gasoline trimmer engine started. With what to start troubleshooting, when the lawnmower does not start, consider step by step with all the details.

Why the grass trimmer does not start (gasoline)?

Because it has worked its. Why, there could be any number of answers to this question. Bad fuel is not an argument. Maybe a person does not know how to use it, so it does not start correctly. No fuel, plug is broken, the wire is broken, not turned on, does not know how to use, trimmer for grass burnt / broken, so on what other reasons may be. There is also such a. hands hooks.

There may be several reasons why a gasoline grass trimmer won’t start.

If the grass trimmer does not start or immediately stops after starting, the problem may be in the fuel tank (namely the quality of fuel), in the spark plug and the spark plug conduit, in the air or fuel filter, in the breather or exhaust duct.

1). Be sure before you start the trimmer for grass, you need to check the availability, and most importantly and the quality of fuel mixture.

2). Grass trimmer may not start or shut down with a primed plug. It will need to be unscrewed and wiped down.

Dry the candle canal for at least 30-40 minutes. Otherwise, the new spark plug may also fill up.

3). If the grass trimmer starts without an air filter, then it is better to replace the old filter with a new one.

4). The grass trimmer may not start if the fuel filter is dirty.

5). Also grass trimmer may not start due to clogged breather valve.

It can also be caused by dirt in the exhaust port or a clogged muffler screen.

Your petrol grass trimmer may stop starting for several reasons at the same time.

First of all: try to clean the carburetor. a clogged carburetor can cause your lawn trimmer to malfunction.

Second: there may be a vacuum in the barrel. If this is the case, try making a small slit in the lid of the barrel.

Third: check that the grass trimmer settings are correct.

There are several reasons why the grass trimmer will not start. Here are the main causes:

  • bad fuel. Each grass trimmer model requires gasoline with a specific octane rating. Check the instruction manual and make sure you’re pouring exactly the right.
  • flooded spark plugs. Check the spark plugs at the same time. Sometimes even new (in the box) spark plugs can be inoperable or defective.
  • no fuel mixture in the carburetor. Pump it up a little.
  • The ignition coil is defective.
  • Muffler blocked. It needs to be free of fouling. To do this, carefully disassemble and clean it (you can burn it on a gas torch).

Usually our grass trimmer would not start after winter, and we used to take the grass trimmer to the workshop almost every spring, where we had it fixed. But, one day, a knowledgeable person advised us to.First, never leave the gasoline in the trimmer for the winter, because the old gasoline can be the reason that the grass trimmer does not start, and also he said that is necessary for starting grass trimmer pumping carburetor fuel mixture. After we began to follow these rules, our problems with the trimmer disappeared.

See also  Champion grass trimmer what gasoline. The most important characteristics and parameters

The first thing to look at is the spark plug. If necessary, replace it, making sure that the spark plug is not punctured and gives a normal spark. The next problem will be hidden in the fuel system. As mentioned above, check the tightness, then check the fuel filter, change if necessary. Clean the carburetor, see the effect. It may be necessary to dig into the ignition system, adjust. To check the fuel system, you can pour a few grams directly into the cylinder through the holes of the plug, screw in the plug and try to start. At least the grass trimmer should make a running engine sound for 1-2 seconds and some smoke should come out of the muffler.

This is interesting: How to ignite the car quickly?

check, spark, plug, trimmer

If the trimmer for grass at you in general does not start or immediately stops after the start, then you first need to look for the cause in the main nodes and units, for this you need in the sequence below to check, so, this sequence:

These components are mainly the cause of the problem.

Replace spark plugs on a BC-43E brushcutter

Spark plugs and malfunctions are associated with their appearance:

  • Wear, more often of the side electrode.
  • Cracking of the body of the insulator.
  • Melting of both electrodes.
  • Erosion. thinning of a side element.
  • Fouling of the spark plugs.

Failure to change the spark plugs in time leads to distortion of the gap and, as a natural result, spark formation with the consequence of a disgusting start of the car. Wear of the lateral electrode is caused by the additives in gasoline. It results in skipping of spark, detonation of engine. Products are replaced.

The reason for changing are even inconspicuous cracks or otherwise visually visible chips on the body of the insulator.

When using candles with cracks, there is a current leakage through the insulator to the body of the candle

The faults are due to a cause:

  • Wear (natural).
  • Detonation due to an early ignition angle.
  • Low octane fuel.
  • Insulator of low quality.
  • Incorrectly set gap.

A lack of spark plug insulator is the cause of current leakage. The fact leads to a decrease in the discharge of spark between the electrodes. It makes hard starting of the engine, low injectivity, jerks when moving from the spot, unbalanced idling speed.

Microcracks are easy to find in the dark or darkness of a garage.

Electrode melting is the manifestation of serious overheating

Rough, porous carbon deposits appear. Occurs due to thermal loading, low octane gasoline, early ignition cycle. Not exclude the faults of the distributor (tramler) on the other valves. Check mixture, ignition, change spark plugs.

How to measure the resistance on the ignition coil?

For this purpose the switch of multimeter is firstly set in position 200 Ohm and measure the resistance of the primary winding, touching the pins “” and “K” with the stylus of multimeter. Resistance should be within the range from 0.2 ohms to 3 ohms (depending on the model of the coil and the accuracy of readings miltimatr).

The grass trimmer does not start. One of the common causes is excessive primer fuel priming, leading to “flooding” of the spark plug. If after 5-6 attempts to start the grass trimmer failed, unscrew and dry the plug. Check spark plug for spark between electrodes.

See also  How to unscrew the head of a trimmer for grass.


All the reasons why the lawnmower does not start, can be systematized according to the specifics of the work of individual nodes. The service center diagnoses malfunctions in a systematic manner:

  • engine malfunction (piston wear, bearing failure, cracked crankcase);
  • Fuel consistency malfunction. clogged air filter pores or carburetor malfunction;
  • The ignition system is not working;
  • Failure of a mechanical nature. leaky hoses, broken wires under the braid, broken tubes.

The user should first check that there is fuel in the tank. Start in accordance with the instruction manual with the saw on its side. Gasoline grass trimmer, starts up without any problems. May not start. Turn the choke shutter to the “close” position, pump the fuel, turn the ignition on and give 3 to 4 jerks with the starter motor. If the engine is running, open the air damper. Does not start the lawnmower. repeat the operation with a slightly open air damper.

The lawn mower can not run for a long time. The gearbox and the engine will overheat. It is possible to mow for less than 15=20 minutes, making a five minute break. Working time is halved on a hot afternoon. When mowing weeds, sedges and thistles, you need to reduce the operating time.

If the start fails, we start to find the cause of the failure:

  • Check the fuel quality;
  • make sure that the spark plug is working and the spark plug channel is clean;
  • check that the air filter is clean;
  • check that the fuel filter is not clogged;
  • check breather plug cleanliness;
  • clean the exhaust port.

complex causes will be, discovered during the diagnosis of malfunctions, leading to an overhaul of the carburetor. Such causes include clogging of carburetor internal passages, wear of the gasket on it and violation of tightness of internal hollows with loss of vacuum. Causes of gasoline breakdowns and why the gasoline grass trimmer does not that dvs does not start. Repair the lawnmower with their own hands, if it does not start, will require patience.

Causes of coil malfunction

Partial damage to the ignition coil leads to unstable engine operation, and its complete failure makes it impossible to start the engine. That’s why when the engine trots, loses power or other signs of fuzzy operation, one of the first actions should be to check the ignition coil. This element fails quite rarely, and the malfunction is usually as follows:

  • Damage to the insulation due to extreme heat, vibration, or high voltage, which in turn causes a short circuit in the coil windings;
  • Overloading caused by faulty high-voltage wires or spark plugs can lead to winding failure in the coil.

Why do you need a good spark?

The quality of the spark determines its ability to ignite a properly formed air-fuel mixture under operational criteria. A weak spark in the criteria of high pressure and temperature in the combustion chamber can not do it. Ignition is late or does not happen at all. How to check the ignition coil on a trimmer by yourself. There is a bulge in the work of the engine, the motor does not gain speed, there is vibration, detonation, in the starter can show the effect of “backfire”.

Missing spark on a chainsaw repair with your own hands.

How to check the inductance coil with a tester?

The symptoms of a faulty ignition coil

  • The engine is periodically at a standstill, with time the rpm sags become stronger and more frequent, the engine is more at a standstill when cold.
  • RPM sags at high pressure on the gas pedal.
  • In cloudy, rainy weather, the engine throws up more often.
See also  Changing lines in the trimmer head

Why the lawn mower does not start? Grass trimmer malfunction diagnosis

In this video we will try to review the main malfunctions that occur during the operation of the.

Lawn mower does not start when hot. pull the throttle trigger and yank the cord sharply several times until the motor starts, then put the trigger down. No lawn mower starts no lawn mower causes if there is no spark when cranking. The engine does not start. a specialized repair is required.

Checking the ignition system, if the lawnmower does not start, is carried out sequentially:

  • Clean the removed spark plug from soot and dirt, dry it, set the gap of 1 mm;
  • connect to the high-voltage wire and check for sparks by yanking the starter several times;
  • If there is no spark, check for continuity of the high-voltage wire;
  • Replace the spark plug;
  • Dry the spark plug line;
  • at the same time check the operation of the ignition coil, it is faulty if the working spark plug does not spark.

If the ignition coil is defective, the lawnmower does not start when hot, stops or runs erratically.

Cleaning or replacing the air and fuel filter will ensure the proper flow of ingredients going into the carburetor. The air filter can be washed in soapy water or replaced. If nylon cloth is used, wash it; the porous felt filler is replaced. Replace the fuel filter carefully, without leaving the intake pipe open. Is it necessary to replace the air filter

, You can tell if the engine starts with the air cleaner removed. If your lawn mower won’t start, a dry spark plug will tell you whether or not you need to change the grid on the fuel supply.

The breather hole, the air inlet to the gas tank. Entrance and entry to if the gasoline grass trimmer does not start well or lawn mower is better. If it is clogged, it creates a vacuum in the tank and the mixture does not flow into the carburetor. The hole can be blown with air or cleaned with a needle. Clean the exhaust duct, remove the muffler’s anti-spark screen.

How to avoid most problems?

The work of this seasonal equipment is very influenced by its proper storage. And this applies not only to a long “rest” in winter, but also to short periods of inactivity. To protect yourself and the technique from problems, you need to adhere to a few simple recommendations.

  • Before sending it to a well-deserved rest, the tank of the grass trimmer is emptied of residual fuel. To remove all the mixture, start the lawnmower and let it work until the engine stalls.
  • The first operation after “winter hibernation” is to pour a small amount of oil into the spark plug hole. Before this, the piston is moved to its extreme position. This lubrication will make start-up easier and prevent premature wear and tear.

Before you start working with the brushcutter, it’s essential to check the spark plug and all the main components of the machine.

The reasons why the grass trimmer does not start, quite a lot. But you can find and correct most of the problems yourself. The main thing is the right diagnosis, care and sequence of actions. And how you can solve the problems, the master will tell you in detail from the following

| Denial of responsibility | Contacts |RSS