What are the reasons why your lawn mower won't start?

There are three main reasons why the lawn mower cannot start: a fault with the fuel system, a fault with the circuit system; and insufficient cylinder compression.

Generally speaking, the three major problems will not exist at the same time. Therefore, when a machine cannot start, you should first determine the cause of the fault, determine which system the fault is in, and then take measures. Don't rush around. You can check according to the following steps.

① First, turn the starting wheel by hand. When it passes the top dead center, it feels more laborious. After turning the top dead center, the starting wheel can automatically turn through a larger angle, indicating that the compression is normal. For new machines or machines after overhaul, Compression is generally good.

② There is no explosion sound in the cylinder when starting, the exhaust pipe is weak, and the discharged gas is dry and odorless. This phenomenon mostly indicates problems with the oil system. You should check whether the fuel tank switch is turned on, the amount of oil in the tank, whether the oil line joint is loose, and press the carburetor thickener lever a few times to see if there is oil flowing out. When it is found that the above parts are normal and still cannot be started, you can pour gasoline into the spark chamber hole and start again. If it still fails to start or smoke occasionally ignites a few times and then goes out, it means that the measuring hole in the carburetor may be clogged. Remove the float chamber, take out the measuring hole, and use blowing or cleaning to clear it. Do not use metal wire to clear it. Measure the hole.

③There is no explosion sound in the cylinder during startup or the explosion noise is confusing, the carburetor or muffler backfires, and the gas discharged from the muffler is moist and smells of gasoline. The above phenomena are mostly caused by faults in the circuit system.

When there is no explosion, you should first remove the spark chamber, place the spark chamber on the spark plug guard on the high-voltage line, contact the spark chamber side electrode with the metal part of the machine, and quickly turn the starting wheel to see if there are any blue sparks jumping. If not, check each component of the circuit separately. For old machines, if the circuit and oil circuit are normal but still cannot start, you can further determine whether the compression pressure is too low. At this time, you can remove the spark plug and pour a small amount of oil into the cylinder, and then install the spark plug. If it can catch fire, it means that the cylinder compression is not good. The cylinder head should be disassembled to check whether the cylinder gasket is damaged. Remove the cylinder and check whether the piston ring and cylinder are excessively worn.

④Every part is in good condition. Because the starting environment temperature is too low and the machine is too cold, the gasoline is not easy to atomize and it is not easy to start.

⑤ If the pipeline connection is not tight, there is too little oil and too much air, or the air filter is clogged, there is too much oil and too little air, it will be difficult to start.

⑥The direction of the starting pull rope and the starting speed also have an impact on whether it can be started.

⑦If the opening of the inner door is blocked improperly during startup, it will not be easy to start.