In order for a four-stroke scooter engine to work perfectly, you only need three things: a spark, fuel and compression. When troubleshooting, you should adhere to the following rule - everything is checked gradually, starting from the most basic faults and ending with the repair of the main parts of the moped.
The first thing to check is the presence of fuel in the tank and in the system. Then we check for the presence of a spark. The engine will not start if the quality of the mixture is poor , or if the carburetor is clogged.
Major engine malfunctions
- The engine will not start.
- The starter turns over, but the engine does not start.
- The engine runs erratically or there is a loss of power.
- A specific knocking sound appeared in the engine during operation.
If the ignition key is not turned, the fuse is blown, or the battery is low, the engine will not show any signs of life. Therefore, before moving on to global repairs, you should check these reasons.
Possible reasons: a spark plug is broken, the carburetor is clogged, fuel is not entering the system.
This may indicate that the carburetor is clogged, the oil or air filter is clogged, the head valves are out of adjustment, or the variator or piston group is worn out.
This may be a sign that the bearings have failed and need to be replaced. It may also be due to the need to adjust the valve clearance.
Repair of scooters and mopeds in Moscow
1. General provisions
This personal data processing policy has been drawn up in accordance with the requirements of the Federal Law of July 27, 2006. No. 152-FZ “On Personal Data” and determines the procedure for processing personal data and measures to ensure the security of personal data taken by the owner of the website service-mopedov.ru (hereinafter referred to as the Operator). 1.1. The operator sets as its most important goal and condition for carrying out its activities the observance of the rights and freedoms of man and citizen when processing his personal data, including the protection of the rights to privacy, personal and family secrets. 1.2. This Operator’s policy regarding the processing of personal data (hereinafter referred to as the Policy) applies to all information that the Operator can obtain about visitors to the website httpsː//service-mopedov.ru.
2. Basic concepts used in the Policy
2.1. Automated processing of personal data – processing of personal data using computer technology; 2.2. Blocking of personal data – temporary cessation of processing of personal data (except for cases where processing is necessary to clarify personal data); 2.3. Website – a collection of graphic and information materials, as well as computer programs and databases that ensure their availability on the Internet at the network address httpsː//service-mopedov.ru; 2.4. Information system of personal data - a set of personal data contained in databases, and information technologies and technical means that ensure their processing; 2.5. Depersonalization of personal data - actions as a result of which it is impossible to determine without the use of additional information the ownership of personal data to a specific User or other subject of personal data; 2.6. Processing of personal data – any action (operation) or set of actions (operations) performed using automation tools or without the use of such means with personal data, including collection, recording, systematization, accumulation, storage, clarification (updating, changing), extraction, use, transfer (distribution, provision, access), depersonalization, blocking, deletion, destruction of personal data; 2.7. Operator - a state body, municipal body, legal or natural person, independently or jointly with other persons organizing and (or) carrying out the processing of personal data, as well as determining the purposes of processing personal data, the composition of personal data to be processed, actions (operations) performed with personal data; 2.8. Personal data – any information relating directly or indirectly to a specific or identified User of the website httpsː//service-mopedov.ru; 2.9. User – any visitor to the website httpsː//service-mopedov.ru; 2.10. Providing personal data – actions aimed at disclosing personal data to a certain person or a certain circle of persons; 2.11. Dissemination of personal data - any actions aimed at disclosing personal data to an indefinite number of persons (transfer of personal data) or familiarizing with personal data to an unlimited number of persons, including the publication of personal data in the media, posting in information and telecommunication networks or providing access to personal data in any other way; 2.12. Cross-border transfer of personal data – transfer of personal data to the territory of a foreign state to an authority of a foreign state, a foreign individual or a foreign legal entity; 2.13. Destruction of personal data – any actions as a result of which personal data are destroyed irrevocably with the impossibility of further restoration of the content of personal data in the personal data information system and (or) the material media of personal data are destroyed.
3. The Operator may process the following personal data of the User
3.1. Full Name; 3.2. Phone numbers; 3.3. Email address; 3.4. The site also collects and processes anonymized data about visitors (including cookies) using Internet statistics services (Yandex Metrica and Google Analytics and others). 3.5. The above data below in the text of the Policy are united by the general concept of Personal Data.
4. Purposes of processing personal data
4.1. The purpose of processing the User’s personal data is the conclusion, execution and termination of civil contracts; providing the User with access to services, information and/or materials contained on the website httpsː//service-mopedov.ru; clarification of order details. 4.2. The Operator also has the right to send notifications to the User about new products and services, special offers and various events. The User can always refuse to receive information messages by sending the Operator an email to the email address marked “Opt-out of notifications about new products and services and special offers.” 4.3. Anonymized data of Users, collected using Internet statistics services, serves to collect information about the actions of Users on the site, improve the quality of the site and its content.
5. Legal grounds for processing personal data
5.1. The Operator processes the User’s personal data only if it is filled out and/or sent by the User independently through special forms located on the website httpsː//service-mopedov.ru. By filling out the appropriate forms and/or sending his personal data to the Operator, the User expresses his consent to this Policy. 5.2. The Operator processes anonymized data about the User if this is allowed in the User's browser settings (saving cookies and using JavaScript technology are enabled).
6. The procedure for collecting, storing, transferring and other types of processing of personal data
The security of personal data processed by the Operator is ensured by implementing legal, organizational and technical measures necessary to fully comply with the requirements of current legislation in the field of personal data protection. 6.1. The operator ensures the safety of personal data and takes all possible measures to prevent access to personal data by unauthorized persons. 6.2. The User's personal data will never, under any circumstances, be transferred to third parties, except in cases related to the implementation of current legislation. 6.3. If inaccuracies in personal data are identified, the User can update them independently by sending a notification to the Operator to the Operator’s email address marked “Updating personal data.” 6.4. The period for processing personal data is unlimited. The User may at any time withdraw his consent to the processing of personal data by sending a notification to the Operator via email to the Operator's email address [email protected] marked “Withdrawal of consent to the processing of personal data.”
7. Cross-border transfer of personal data
7.1. Before the start of cross-border transfer of personal data, the operator is obliged to ensure that the foreign state into whose territory it is intended to transfer personal data provides reliable protection of the rights of personal data subjects. 7.2. Cross-border transfer of personal data to the territory of foreign states that do not meet the above requirements can only be carried out if there is written consent of the subject of personal data to the cross-border transfer of his personal data and/or execution of an agreement to which the subject of personal data is a party.
8. Final provisions
8.1. The User can receive any clarification on issues of interest regarding the processing of his personal data by contacting the Operator via email [email protected] 8.2. This document will reflect any changes to the Operator’s personal data processing policy. The policy is valid indefinitely until it is replaced by a new version. 8.3. The current version of the Policy is freely available on the Internet at httpsː//service-mopedov.ru.
DIY 4-stroke scooter engine repair instructions
- Remove the engine from the scooter. We install the scooter as stable as possible. We remove the trunk. Disconnect all wires from the engine and the throttle cable from the carburetor. Remove the gas hose and vacuum filter. Disconnect the rear shock absorber. After the engine is separated from the frame, unscrew the nut on the mounting axle and remove the axle. After removal, it is advisable to wash the engine.
- Removing the cylinder head. It is necessary to clean the chamber from carbon deposits. In order to remove the head, you must first disconnect all the “extra” parts. Then the chain tensioner bolt and locking bolts are unscrewed. Then we turn the flywheel until the T designation matches the one on the engine body. We unscrew the bolts that secure the cylinder and remove the chain, and then the cylinder head itself.
- Valve clearances must be adjusted if metallic knocking occurs. The principle of operation is as follows: the valve mechanism cover is removed. We correlate the mark on the flywheel with the mark on the engine housing. We measure the gap between the adjusting screw and the valve stem. When increasing or decreasing the gap, we adjust by rotating the screw.
As practice shows, it is better to entrust major engine repairs to professionals, since many nuances arise that the average driver does not pay attention to, but which in the future can create even bigger problems and then more expensive repairs will be required. A video about repairing a 4-stroke scooter will introduce you to the main aspects of repair.
Do-it-yourself repair of individual parts
Having determined that neither spark plugs nor gasoline are the cause of the malfunction, we move on.
As noted earlier, engine problems can vary. Very often these problems are associated with spark plugs or the carburetor. The spark may not jump due to carbon deposits on the spark plug, which occurs due to the use of a rich mixture.
There may be a small gap, which also does not contribute to the appearance of a normal spark. In a two-stroke engine this gap is 0.6-0.7 mm. With a smaller gap, there is a high probability that the electrodes will melt. Increasing the gap causes current consumption to increase and more voltage is required to produce a spark.
There are situations when the moped stalls while moving, and then continues to move on. This occurs due to the detachment of carbon deposits from the electrode. For some time the spark is lost and the engine stops working. After self-cleaning, performance is restored.
Interruptions in engine operation may be due to moisture getting on electrical appliances and wiring. This results in a loss of voltage. After drying these parts , engine operation should be restored.
A fairly common cause in our climate is water getting into the fuel and then into the carburetor .
The reasons considered are easily eliminated by the driver themselves. However, if these steps do not bring the desired solution and the engine does not work, the scooter engine should be repaired.
Carburetor repair
As for the carburetor, the causes of malfunctions may be caused by improper mixture quality. If the mixture is lean or rich, the performance of the moped will be at risk. The quality of the mixture can be checked by the condition of the candle. A black color will indicate that the mixture is rich, that is, there is excessive oil consumption. White color will indicate a lean mixture and a decrease in engine power for this reason.
Repairing a scooter carburetor is performed on a warm engine. Before this, if there is a possibility of clogging, it should be cleaned and washed. The carburetor adjustment itself consists of the following actions:
- Step 1 – you need to adjust the idle speed.
- Step 2 - check and adjust the quality of the mixture for the carburetor using a special screw.
- Step 3 – set the quality of the mixture by moving the needle.
- Action 4 – adjusting the fuel level in the float chamber.
This action is performed using the idle screw. In order to increase the speed, the screw is tightened, and to decrease it, it is unscrewed. After warming up the scooter, with the help of simple manipulations, you can set up stable idle operation of the engine.
The combustible mixture that enters the carburetor must clearly have the proportions set by the scooter manufacturer. If the mixture is too lean, the scooter loses power and overheats. With a rich mixture, fuel is used uneconomically. This problem can be solved by turning the screw. Turning the screw clockwise enriches the mixture, counterclockwise turns it leaner. The quality of the mixture will be indicated by the color of the candle. The candle is black and has carbon deposits, which means the mixture is rich. If, on the contrary, it is white, the mixture must be enriched.
The following manipulations are performed with the needle: when raising the needle, the mixture is enriched, and when lowered, it is leaner.
Checking the fuel level is done with a transparent tube located at the bottom of the carburetor. The procedure is as follows: unscrew the oil screw, lift the tube up and check the fuel level. The fuel level is monitored while the engine is running. The tube should be kept above the carburetor. The fuel level should be slightly below the curb of the carburetor cover.
Features of repair of Chinese mopeds
Repairing Chinese engines does not cause any particular difficulties for most scooter owners. It should be remembered that the main fastenings of the “Chinese” are more delicate than in domestic mopeds, so there is no need to pull anything with all your might.
For example, sudden movements when repairing the carburetor of a Chinese scooter can damage the pipe . Then the muffler is removed. Many Chinese scooter manufacturers use plastic soldering. This must be taken into account when disassembling the moped.
Manufacturers have foreseen that many scooter owners will want to carry out repairs themselves, so there is simply nothing complicated in the design of such scooters. The repair manual for Chinese scooters will allow you to perform all the steps yourself. Anyone can figure out the main problems and repair the engine of a Chinese scooter.
A scooter repair video will answer most questions.
