Repairing, adjusting and cleaning the carburetor is a rather complicated procedure. However, having delved into the technology of its implementation, each owner of a motorcycle or scooter will be able to perform all actions independently. To do this, you need to familiarize yourself with the details of this process, as well as allocate a sufficient amount of free time.
Japanese-made Keihin carburetor has the same device in all models. For other manufacturers, the principle of cleaning and adjustment is similar. Therefore, as an example, this carburetor brand fits perfectly. The operation of a motorcycle depends on the correctness and responsible approach to cleaning and adjustment.
Carburetor Service Need
If you have a Honda, Kwasaki, Navigator scooter or other two-wheeled motor equipment, you should understand the importance of periodically servicing a carburetor. Power, ease of start, speed and control of the motorcycle depend on this system.
In order for the fuel mixture to be supplied with the same quality fuel mixture, it is necessary to correctly regulate the operation of the carburetor. Synchronization allows you to adjust the amount of gasoline and air that, when mixed, enter the engine.
Experienced drivers know that the carburetor on a scooter needs to not only be adjusted, but also cleaned during maintenance. In gasoline there is a certain amount of additives, impurities. When the motor is running, they settle on the walls of the system, forming contamination of the nozzles. To ensure that the carburetor can perform its functions in full, it is necessary to periodically clean it from dirt and soot accumulated inside.
When is maintenance required?
The carburetor ( Keihin PZ30 , CVK - it doesn’t matter) of all popular models has a similar principle of maintenance. Therefore, the symptoms of the need for this procedure in all cases will be similar symptoms.
The main reason for carburetor adjustment is the uneven operation of the motor. It appears at idle. There may also be pops coming from the muffler, increased gas mileage. The driver should periodically pay attention to the appearance of the candles. Significant changes in their color indicate violations of the preparation of the fuel mixture.
Candles can be considered the main indicator of the carburetor. If they are white, the mixture is considered poor. Too much soot on candles indicates the preparation of a rich mixture. This is a deviation from the norm. The cause may be a dirty carburetor or a malfunction in its settings. In this case, maintenance is carried out as soon as possible. Periodically also clean the system. It depends on the frequency of use of the motorcycle.
Carburetor removal
To clean the Keihin carburetor , it will need to be removed. To get to it, you will need to remove the airbox and gas tank. Then the clamps of the manifold branch pipes are loosened. The suction cable (enrichment) is dismantled.
Honda Scooter and other models of such vehicles have a system of carburetors that are in the same row. For cleaning, it is not necessary to separate them from each other. However, to replace the seals will have to disassemble the line.
When dismantling, the carburetor block is removed, as well as gas cables. Now you can easily perform system maintenance. The top covers must be removed (the screws are loosened). Next, you need to inspect the condition of the gaskets, needles and rubber bands.
The inside and the carburetor itself, as well as the parts around it, must be well cleaned. For this, a bath with gasoline and an ordinary paint brush are suitable.
Block disassembly
If you want to disassemble the carburetor block, the next step is to dismantle the intermediate plate between them and the air filter. Next, unscrew the bolts on the bar holding the unit together. Keihin CVK or another model usually requires great physical effort. Most likely, you will need to use a screwdriver with a T-shaped handle.
Next, disconnect the return spring. For this, bolts are also unscrewed in appropriate places. The bar slides easily and detaches from the structure.
Between themselves carburetors fixes a long bolt. It must also be dismantled. You can disassemble the unit. The first carburetor is removed and the spring is laid aside. They can not be confused in places (differ in size). Then the housing is cleaned from the outside.
Carburetor Block Maintenance
The scooter carburetor may need a diaphragm change. In some cases, it is also necessary to completely replace one of the elements of the block. The internal metal surface of the device may oxidize over time. Therefore, you need to replace the diaphragm. It is very carefully removed with a screwdriver.
This item can be accessed with a metering needle and a shutter. Further, if necessary, the old components can be replaced.
After that it is necessary to unscrew the screws of the float chamber. Its cover is removed. You can evaluate the performance of the float by tapping it lightly. If this element is springy, then its operation is correct. No replacements required. When disassembling, it is very important to use a suitable size screwdriver. All work must be carried out very carefully.
Cleaning
Keihin carburetor after dismantling requires thorough cleaning. To do this, you need to purchase a special tool. It must not destroy rubber seals. Many similar cleaners are on sale. It is convenient if the product is in the bottle. Using a special tube, it will be easy to spray it throughout the mechanism.
Work must be carried out outdoors. Solvents contain many hazardous components. Therefore, indoors, such work is highly discouraged.
The carburetor is blown under pressure with air. If necessary, some areas can be cleaned manually with cotton swabs. If the length of the springs is significantly different (by 1.5 mm), they must be replaced.
Carburetor assembly
After proper cleaning and replacement of all obsolete parts, the carburetor is installed in its previous position. Assembly is performed in reverse order. When installing the diaphragms, the return spring must be correctly installed in the seat. If it is not easy to install it in place, the part must simply be turned.
When installing the shutter, it is necessary to monitor the position of the needle. She should not shift to the side. If necessary, lubricate parts with grease.
Then the cylinder block is assembled in reverse order. To do this, you need to prepare the appropriate tool. All carburetors have differences. Therefore, when disassembling, you need to number them. Installing a carburetor requires a scrupulous attitude. All bolts, springs, must be assembled very carefully. It is better to record the sequence during disassembly so as not to lose a single structural element.
Synchronization
After cleaning, Keihin carburetor adjustment is required. You can start with synchronization. This is a simple procedure. But she will need a synchronizer. This device checks sparseness.
The motorcycle must be warmed up to the engine operating temperature. Then the tank and filter are removed. The synchronizer will help to establish the same sparseness in the collector. The device connects to it. The engine starts.
According to the readings of the sensors, the valves must be adjusted. They should respond (but slightly) to changes in sparseness. If the arrow of the synchronizer does not accept changes, the valve needs to be released. The process is carried out using the appropriate screws on the carburetor. First, adjust the right and left screw. Only then can the central lever be adjusted.
Idle adjustment
After high-quality cleaning, the idle speed is adjusted. To do this, the motor must be warmed up well. To do this, you need to start the vehicle and wait 10-15 minutes.
Next, refer to the manufacturer's instructions. It indicates where the adjustment screws are located. Guided by this knowledge, you can begin the process. A screwdriver, with which all the settings will be made, is better to mark. On one side it is necessary to stick a marker. This will allow you to understand how many revolutions have been made.
At idle, it is necessary to tighten the corresponding screw. If you clamp it, the speed will increase, and vice versa. The adjustment is performed until the engine is idling stable.
Mix quality adjustment
If the idle adjustment is successful, you can begin to adjust the quality of the fuel mixture. She should not be too poor or rich. The adjustment is made using the adjusting screw or by moving the needle in the throttle flap.
The motor must be warmed up before tuning. This procedure is carried out only for a clean carb. Most often, for normal operation of the system, you need to unscrew the screw from the extreme position by 1.5-2 turns. But many reasons affect this indicator.
If you turn the screw clockwise, the mixture is enriched, and vice versa. If you lower the needle, the mixture is lean. With a combination of both settings, it is possible to achieve the exact operation of the fuel supply system to the engine. If the procedure is performed correctly, the motorcycle will accelerate smoothly. When moving there will be no jerking
Fuel level adjustment
Keihin carburetor adjustment is completed by checking the fuel in the float chamber. To do this, prepare a transparent tube. It is located at the bottom of the system. The drain screw must be unscrewed. Then the tube rises up, in the opposite direction from the carburetor. The fuel level is checked.
The check is carried out with the working engine of the motorcycle. The tube should always be above the carburetor. Fuel should be slightly lower than the lid curb.
Having examined the Keihin carburetor , as well as its device and maintenance, each owner of the vehicle will be able to clean and adjust himself. This will extend the life of the vehicle, make it safe and comfortable to drive. The driver will be able to perform almost all the actions on their own, without contacting a car service.