Why A Scooter Carburetor Floods: Search For Causes And Their Elimination.

The technique has one bad property. it breaks. It is no exception to this rule for scooter. A carburetor is a frequent problem in the operation of a scooter or moped. a device that prepares the fuel-air mixture. This article draws attention to the following problem: why it fills the scooter carburetor.

Causes of failure.

It is possible to determine that the carburetor is poured by several signs:

  1. The condition of the candle. A dirty spark plug indicates a rich combustible mixture, which means a high content of gasoline. Even a serviceable or new candle can not cope with the flow of fuel entering the cylinder and over time will be covered with soot, it will be constantly wet, and the engine will cease to start.
  2. Gasoline flows out through the air filter. In the case of the air filter can be found signs of fuel.
  3. Gasoline flows through the gasket of the float chamber.

It should be noted that these signs may appear both on their own and after repair. What are some reasons why a carb can pour?

Failure of the fuel crane.

Tanks are equipped with vacuum fuel cranes with three outputs. One of them. the intake of fuel from the tank, the other supply of fuel to the carburetor. The third output is designed, to sum up, the vacuum hose. When creating a vacuum in the engine, the crane membrane begins to pump fuel.
Tip! If the engine does not start after a long period of inactivity (no fuel has been injected), in order not to wait until the engine loads it, you can remove the vacuum hose on the other side of the tap and create a vacuum with your mouth until the carburetor is full.

Clogged air filter.

With an insufficient amount of incoming air, the scooter can also pour fuel. It is possible to diagnose the filter on passability of air as follows. Just disconnect the air filter. If now the engine began to work correctly, then it is necessary to change the air filter. When all the same it fills the carburetor on a scooter without a filter. “dig deeper”!

Stop needle.

Briefly about the principle of operation of the float chamber. Fuel enters it, thereby raising the float. The float, rising, lifts the locking needle behind it. With enough fuel in the chamber, the locking game closes the fuel supply hole.
If the locking needle is worn out (erased tip or metal body), then it cannot completely block the feed opening, and gasoline continues to flow. The same effect is obtained if a speck (grain of sand) gets under the stop needle.


What to do if you had to face such problems? Let’s take it in order. You need to start with the air filter. if there are no problems with it, then proceed to the following actions.

The problem with the fuel valve?

If gasoline is pouring out of the fuel supply hose all the time, even when the vacuum hose is removed, the valve is defective. It simply does not work but is always in the open position. In this case, the valve must be replaced with a new one.
If however, when the vacuum hose is removed, gasoline stops flowing, then the reason is in a constant vacuum. it is necessary to climb into the cylinder head.

Stop needle.

Under the condition of a working crane, you can sin on the locking game. How to get to the needle of a scooter or moped?

  • To remove the carburetor, you must disconnect the air filter; hoses suitable for it; unscrew it from the intake manifold and remove the gas cable.
  • Next, using a Phillips screwdriver, remove the float chamber housing.
  • Assess the condition of the locking needle, and antennae float.
  • If necessary, replace the needle and fold the antennae of the float. If the needle is in good condition, then its seat should be thoroughly rinsed and blown.
  • Collect everything back and install on the engine.

Vacuum booster (if nothing helped).

In addition to the locking needle, a vacuum needle (vacuum accelerator) is also installed on Chinese scooters. This device also works from a vacuum hose supplied to the “carbs”. This needle has 5 (usually) adjustment positions. When the scooter accelerates, this needle opens under the action of vacuum and more fuel is fed into the combustion chamber.
The system is correct. However, everything breaks down. Over time, none of the provisions of the needle does work. Such a problem is solved simply by removing or cutting the vacuum hose (not that to the fuel tap)! And the engine no longer pours. a miracle of miracles.


Having studied this material, you can independently cure your scooter or moped of the problem of the transfusion of gasoline. Rinse all thoroughly and be attentive to the little things!