Author: Site Editor Publish Time: 2022-03-03 Origin: Site
The factory assembles the carburetor on the custom RC car engine, usually set by the factory.
The custom RC car carburetor contains three sets of tuning needles:
High-speed oil needle: used to control the fuel supply in any direction.
Low-Speed Needle (Front and Rear): Controls fuel supply at idle and low revs.
Idle speed adjustment screw: Control the closing space of the air valve at idle speed.
When tuning the low-speed oil needle, there will be obstacles to block and increase tuning difficulty. Keep adjusting according to the principle:
Use the idle speed adjustment screw to adjust the closing space of the control valve at idle speed.
Use the low-speed oil needle to adjust the fuel supply after closing the carburetor valve for 2-5 seconds.
Use the front low-speed oil needle (on the carburetor's gas valve) as a basic tuning (off the track).
Use the rear low-speed oil needle (at the rear of the carburetor housing) as a final tune (on the track).
Only the tuning range of 1/2 turn can be used.
Only make a slight adjustment at a time and only make a twist of 1/8 of a turn at most, especially on the final adjustment. The custom RC car's engine is responsive to slight changes in the mix settings.
The specific steps of oil needle tuning
The custom RC car engine needs to run to operating temperature (about 15-20 seconds) before performing the following steps:
The first step is to set the high-speed oil needle to have a bit of rich oil, take the car off the ground, and fully open the air valve. Let the engine clear the oil to reach 80% of the maximum speed. Then it should be slightly more decadent than when it was started: If the engine can reach the maximum speed after running the oil, increase the high-speed oil needle (counterclockwise) only when starting ( 4-stroke sound) to about 80% of top speed. If the engine is running too rich, turn the high-speed oil needle (clockwise) down to just start (4-stroke sound) to about 80% of top speed.
Step 2: Set the idle speed to lift the car off the ground and fully open the air valve for 2-3 seconds. Then close the carburetor valve and check if the engine can respond to idle speed immediately. If the engine shuts off immediately, turn the idle speed adjustment screw clockwise until the idle speed is stable. If the engine idle speed is too high, turn the idle speed adjustment screw counterclockwise to reduce the idle speed.
Step 3: Set the low-speed oil needle to fully open the carburetor for 2-3 seconds and let the engine clear the oil. Then close the carburetor and let the engine idle. If the engine slows down to idle after 2-5 seconds, the engine is too rich at low speed. Adjust the low-speed oil needle (clockwise) to the proper size. Repeat this step until the carburetor is fully opened for 2-3 seconds and then closed, and the engine can idle for 20-30 seconds. If the idling speed increases rapidly after 2-5 seconds of idling, the engine is prone to chasing fuel. To correct this situation, the low-speed oil needle should be increased (counterclockwise).
If the engine is not idling, increase the low-speed oil needle (counterclockwise), or twist the idle-speed adjustment screw until the idle speed is stable.
Note: Because adjusting the low-speed oil needle will affect the idle speed, please use the idle speed adjustment screw to adjust the engine speed to the average speed. If you are satisfied that the carburetor you tuned has the actual reliability settings, you can put your car on the track and run.