Situation: yesterday your car was driving normally, and in the morning refuses to start. It would seem that you need to follow the car service, but how to actually go? Before calling the tow truck, we will try to deal with the problem in place.
Why the engine will not start (we take the following situation as a reference point: the battery is in order, the starter rotates vigorously, there is gasoline in the tank).
- There is no power on the coil of spark plugs (or the candles do not work): they unscrewed the candle, put it on the motor housing, twisted the starter. there is a spark;
- Gasoline does not enter the carburetor (we are considering just this type of engine, everything is much more complicated in the injection system).
What is needed to check the fuel supply system in the carburetor?
Consider the solution to the problem on the example of a common VAZ 2109 car.
- several screwdrivers (slotted and Phillips);
- set of wrenches;
- automobile compressor (there is in the trunk of a self-respecting driver);
- capacity (can a PET bottle);
- clean rags.
Troubleshooting is conducted on the principle: from simple to complex. Reasons why gas supply to the carburetor is disrupted:
- Remember the last time the fuel filter was changed. Perhaps he is just clogged with dirt;
- Water got into the gas line, and an ice plug formed (relevant for sub-zero temperatures, “cured” with a cup of hot water);
- Lack of pressure in the fuel line. commonplace leaks at the joints. Pay attention to the smell of gas around the car after trying to start;
- There is an obstacle in the hose from the gas tank. a piece of rust, a plug of dirt;
- Breakdown of the fuel pump;
- Clogged mesh filter near the fitting in the carburetor.
To determine the location of a malfunction, there are two primitive but effective ways of checking:
- Remove the fuel supply rods and press the manual pump lever several times. If the fuel arrives, then the pump is working, we continue to search for the cause in the carburetor. The fuel line from the tank to the pump is also working;
- We pick up a little gasoline in the tank, connect it to the fuel supply hose, and place the bottle as high as possible. We are trying to start the engine. If the engine starts up, the reason is in the chain: gas tank, fuel line, filter, pump.
Next, we look for the cause in the localized nodes.
Carburetor test sequence
On the test machine, the engine air filter is located directly on the carburetor. Therefore, for access it must be disassembled.
- Remove the filter cover with the key. We take out the filter element (at the same time we check its purity) and unscrew the bolts securing the casing to the carburetor. Remove the case;
- We look inside the carburetor. Depending on the temperature of the engine, the throttle can be opened or closed. In the second case, open it with your hand. Then we click on the drive of the throttle mechanism, and check if a stream of gasoline has appeared from the pump;
- After making sure that there is gas in the carburetor, we get into the car, press the “gas”, and try to start the engine. If it does not start, look further;
- We remove the top cover of the carburetor so that the fuel level in the carburetor chamber becomes visible. The cover is mounted on 5 screws. You should also disconnect the bracket for the gas cable, and turn off the idle valve;
- Having released the float chamber, we estimate the level of gasoline. During normal operation of the fuel supply system, the level should be 23 mm below the walls. You can evaluate the level with the help of a caliper ponytail, having previously set it to a depth of 22-23 mm;
- We put the lid back on, fix it with a pair of screws, and start the engine again, after drowning the gas pedal all the way;
- If the camera is empty, the verification algorithm is slightly different. We put on the cover, leaving a small gap between the upper edge of the float chamber and the plane of the cover. We fix the slot with a flat steel ruler or a small screwdriver;
- We fill the chamber with manual pumping or cranking the crankshaft a few turns with a starter. After filling the chamber, we again try to start up, having previously fixed the lid;
- The motor has started. this is a sign of a malfunction in the needle valve. It should be replaced, since it is almost impossible to restore it.
A proven and restored carburetor can be assembled, although it would be more correct to dismantle it (since you still got to it) and rinse all the internal parts with acetone.
Fuel Supply System Test Sequence
So, the fault is localized: it’s a gas tank-pump-fuel line. The technique is as follows:
- We unwind the clamp and remove the gas hose. We lower its end into the prepared container. Important! We strictly observe fire safety measures. The battery cannot be disconnected, since you periodically twist the starter, cover it with plywood or plastic so that the key that has fallen on the terminals does not cause sparking;
- We pump gasoline manually using the lever of the fuel pump. If there is no fuel, crank the crankshaft 1-2 turns, and again press the lever. There is no gasoline. two reasons: either the pump died, or the hose is clogged;
- By means of exclusion, we check the fuel line. We give pressure to the inlet of the tube using a compressor or a large volume syringe. Air does not pass. the hose is clogged. In winter, you can try to warm it with boiling water;
- The best option for “treatment” is to remove the line, clean it in any way, rinse with clean gasoline;
- Return the cleaned hose to the place, repeat the experiments with filling the float chamber. If gasoline is not supplied, we check the fine filter (located immediately after the inlet fitting);
- The mesh must be clean, without damage. The filter can be washed with acetone;
- A damaged or heavily soiled filter is best replaced. Its cost is low;
- If after all the procedures gasoline does not come naturally, the last weak link remains. the gas pump. It is difficult to restore it, therefore. a replacement.
Video: Gasoline Does Not Receive Into Carburetor Trimmer
The likelihood that after all these operations, the engine will not start. tends to zero. In principle, having a small supply of consumables (this applies to cars with very high mileage), you can not be afraid to remain immobilized somewhere on the highway. Failure of the fuel line or carburetor in motion is unlikely, usually such a malfunction occurs after parking.
Caring for a personal plot, summer residents periodically encounter the fact that the lawn mowing does not start. There are many reasons for tool failure. For the correct diagnosis of the problem, the owner of the unit useful at the cottage needs to know the device and the principle of operation of its individual parts.
- Where to start diagnosing lawn mowers
- Checking the fuel mixture
- We diagnose a candle and a candle channel
- Diagnostics of lawn mowing filters
- Breather and exhaust channel
- complex causes of lawn mowing failure
- Rules for the operation and storage of lawn mowers
Where to start diagnosing lawn mowers
If the lawn mowing does not start or immediately stalls after start-up, it is necessary to check all the main components and assemblies in sequence. The verification algorithm is as follows:
- Fuel tank (fuel quality);
- Candle and candle channel;
- Air filter;
- Fuel filter;
- Exhaust channel.
These nodes are most often the source of major problems that can be fixed after a thorough inspection.
Checking the fuel mixture
Before starting the engine of the gas spit, check the availability and quality of the fuel mixture. Do not save, do not be greedy and do not be clever in this matter. Repair or replacement of the piston group will cost you too much (sometimes up to 70% of the cost of a new tool). It is necessary to prepare the oil-fuel mixture strictly according to the instructions. Calculate its quantity from real needs. Excess gasoline remaining after work over time loses its quality.
We diagnose a candle and a candle channel
If the quality of the fuel mixture is not in doubt, and the lawn mower stalls at start-up, then a filled candle may become the cause. Here, for repair, an ordinary candle key (probably every motorist has it) and a spare candle are suitable.
- We twist the candle and wipe it;
- Dry it thoroughly (do not calcine);
- The excess fuel in the chamber is drained through the spark plug hole and dried;
- We clear an old candle from a deposit by means of a file or a lady’s file;
- We set a gap with a distance of 1 mm (you can check with any coin);
- We return everything to its place and try to start a trimmer.
If the candle is working, the nest where it is completely dry and the lawn mower does not want to start, we lubricate the threaded connection with gasoline. It should be slightly moistened. No matter how wonderful a spark a candle gives out, there is simply nothing to light up in a dry chamber.
If the trimmer motor still does not start, a cause such as the absence of a spark due to poor contact between the spark plugs and the high-voltage wire should be excluded. If the connection is high-quality, but there is still no spark, most likely, your ignition unit has “flown”. Here you can’t do without a master, because the part is not being repaired, but sold as a single unit.
Diagnostics of lawn mowing filters
Another reason that the gas braid stalls may be an air filter. To exclude it, try to remove the filter and start the trimmer without it. If possible, then you will have to change the air filter to a new one, or at least blow out and thoroughly clean the old one.
A gas trimmer may not start up due to contamination of the fuel filter. This is the next step in our algorithm. Here we check the condition of the filter element and, if necessary, replace it with a new one. When replacing, try not to leave the suction pipe completely without a filter, this is prohibited by any operating instructions. Haste can result in repair of the engine piston group.
Breather and exhaust channel
Often, “gentle” branded lawn mowers do not start and stall due to contamination of the breather. The main function of this element is to equalize the pressure in the gas tank. If this unit becomes clogged, a vacuum is created in the tank, which prevents the fuel supply. You can fix the problem by cleaning the breather. You can use a regular needle for cleaning.
Normal operation of the braids with internal combustion engines may be impaired due to the ingress of dirt into the exhaust channel or clogging of the silencer mesh. There is such a problem on older models. You can solve the problem by traditional cleaning and removal of the anti-spark mesh.
complex causes of lawn mowing failure
If the step-by-step algorithm for troubleshooting does not give a result, and your braid still does not start or stalls, it is worth examining the carburetor and the engine itself. A clogged carburetor can be one of the reasons for unstable tool operation. Three main problems can be distinguished here:
- Clogged channels or jets. All this is cleaned with special washes or purged with a powerful jet of compressed air from the compressor. Do not use needles and wire, as passage sections may be damaged;
- Worn carburetor gasket. Output. replacement of failed gaskets;
- Violation of tightness. To check this indicator, you can use an ordinary household tonometer, replacing a manometer with a suitable one. Keep track of the readings: if they do not change, everything is fine, and if the pressure starts to fall, then some part of the carburetor is faulty. We’ll have to find it and replace it with a new one.
If everything is in order with the carburetor, then the gas trimmer may not start due to wear on the piston group. If chips, scratches, or nicks are found on the piston or cylinder, they should be replaced. Piston rings are subject to mandatory inspection. A slight piston loophole while rocking the connecting rod indicates that it is time to change the rings. This procedure is best entrusted to service center specialists.
Rules for the operation and storage of lawn mowers
In order for the lawn mowing to continue well, you need to provide it with good storage and operating conditions:
- during operation, carefully monitor the cooling system, carefully and timely clean the channels in the housing, as well as the fins of the starter;
- if necessary, use solvents, kerosene and other detergents for cleaning;
- do not clean the tool “hot”. let it cool;
- Strictly follow the requirements of the instruction regarding the operating mode, otherwise you may overheat the engine;
- if you do not plan to use the lawn mower in the next month, the fuel mixture must be drained from it, because over time it breaks up into heavy fractions that will uniquely clog the carburetor channels;
- after draining the fuel, let the trimmer idle until it dies, this will help to completely remove the remains of the working mixture.
Before winter storage, follow these steps:
- completely disassemble the braid, rinse and clean all the details that you can;
- inspect the parts for damage, if necessary, eliminate distortions, gusts, bends and any other malfunctions;
- Pour enough oil into the gearbox and clean the air filter;
- you can partially disassemble the motor, flush, blow and grease all moving parts;
- in order to lubricate the piston, you need to unscrew the candle, raise the piston to the dead center with the starter, pour a little oil into the spark plug hole and rotate the crankshaft a couple of times;
- if you are not keeping the lawn mowing house, wind the engine with an oiled rag.