What is the reason for no fuel coming out when unscrewing below the carburetor?

2 Answers
StMolly
07/29/25 10:15pm
Reasons for no fuel coming out when unscrewing below the carburetor are as follows: Excessively lean combustible mixture: The carburetor backfire phenomenon is caused by the combustion flame returning from the intake pipe to the carburetor after the spark plug ignites the mixture, which is attributed to an excessively lean combustible mixture. Carburetor backfire: The mixture becomes so lean that the combustion speed is too slow. The time from the start of mixture combustion to its completion extends until the beginning of the next cycle's intake stroke when the intake valve opens, igniting the mixture in the intake pipe and causing carburetor backfire. Intake valve malfunction: The intake valve is stuck in the open position and cannot close. Reasons for valve sticking include scoring of the valve guide, bending of the valve stem, or loosening of the valve seat, all of which prevent the intake valve from closing properly. The spark plug ignites the mixture, which then ignites the mixture in the intake pipe, leading to carburetor backfire, and the intake valve being stuck open, resulting in incomplete closure.
Was this review help?
12
3
Share
IkerMarie
08/15/25 10:38pm
I've been driving old cars for over a decade and have encountered situations where no fuel flows out when opening the carburetor quite often. This is usually due to fuel line blockages or fuel tank issues. First, check if there's still fuel in the tank—if it's empty, where would the flow come from? If the tank is full, then inspect the fuel lines for any damage, aging, or air leaks, as blocked pipes won't let fuel through. The filter is also crucial; a dirty one can block the fuel. If all these are normal, the problem typically lies inside the carburetor—the float might be stuck, the needle valve could be clogged with dirt or worn out and unable to close, preventing fuel from entering the float chamber. Additionally, if the fuel pump is faulty and not creating suction, it won't be able to draw fuel. This isn't something to handle carelessly; gasoline splashing when opened can easily cause a fire. I recommend parking the car and having a professional mechanic handle it rather than forcing a fix yourself. Regularly cleaning the entire fuel supply system can prevent such headaches, keeping the car in good condition for worry-free long-distance drives.
Was this review help?
8
2
Share
Expand All
More Forum Discussions

What is the phideon?

phideon is the Volkswagen Phideon, a new large and mid-size sedan under the Volkswagen brand. It is built on the same MLB platform as the Audi A6 and equipped with technological features such as a night vision system and a heads-up display. It also features electrically adjustable rear seats with independent ventilation and heating functions. The overall body design of the Volkswagen Phideon follows the design concept of the C Coupe, featuring the signature Volkswagen family-style front design where the front grille integrates with the LED headlights and extends to the sides of the body. The side waistline runs through the entire body and extends to the top of the taillights. Additionally, the taillight design is particularly noteworthy, adopting a two-layer design where the lower layer tapers inward, creating a staggered effect.
18
2
Share

Does the Audi A6 not support lossless music?

Audi A6 supports some lossless audio formats, but it may not support the APE format. You can play lossless music using an SD card. Steps to play lossless music from an SD card: Download music: Download music in the lossless WAV format. If the music is in APE format, you need to convert it to WAV format using a player. Create a playlist: Download an MP3 format song and place it in the same folder as the music list and the lossless music. The generated playlist must be in the same folder as the songs; otherwise, it cannot be played. Copy the folder: Copy the entire folder to the SD card. Insert the SD card into the car, and it will be read and played normally.
1
2
Share

What are the symptoms of a faulty camshaft solenoid valve in a Passat?

Volkswagen Passat camshaft solenoid valve failure symptoms are as follows: Difficulty starting: When the camshaft solenoid valve fails, the valve cannot open and close freely, resulting in difficulty starting the car; Weak acceleration: When the camshaft solenoid valve fails, the oil drain hole may be closed, preventing effective fuel transfer and combustion, leading to weak acceleration; Engine stalling after starting: If the solenoid valve suddenly closes or malfunctions when the car is started, it can cause the engine to stall; Check engine light on: There are many reasons for the check engine light to come on, and a faulty camshaft solenoid valve is one of them.
20
5
Share

How long is the warranty period for Maxus V80?

Maxus V80 warranty period: The original warranty for the whole vehicle is 3 years or 60,000 kilometers, and the powertrain warranty is 3 years or 80,000 kilometers. If you use it frequently, you can purchase an extended warranty policy from the 4S store. Return and replacement during warranty period: If the same fault is repaired more than 5 times, the vehicle can be replaced. Within the three-guarantee validity period (the three-guarantee validity period is 2 years or 50,000 kilometers, whichever comes first), if the cumulative repair time exceeds 35 days, or if the same product quality issue leads to more than 5 repairs, the consumer can request a vehicle replacement. Scope of warranty: For parts that the owner has purchased at their own expense, quality issues arising after repair or replacement at the dealership fall under the scope of spare parts warranty.
14
4
Share

Why does the car air conditioner sometimes blow cold and sometimes hot?

The reasons why the car air conditioner sometimes blows cold and sometimes hot are: 1. Dirty air filter; 2. Damaged blower or air conditioning flap motor; 3. Insufficient refrigerant in the air conditioning system; 4. Dirty radiator or condenser; 5. Faulty air conditioning pressure sensor or evaporator box sensor. The car air conditioning system includes cooling devices, heating devices, and ventilation devices. This combined system makes full use of the limited space inside the vehicle with a simple structure. The car air conditioner is used to adjust and control the temperature, humidity, air cleanliness, and air flow inside the car compartment to an optimal state, providing passengers with a comfortable riding environment, reducing travel fatigue, creating good working conditions for the driver, and serving as an important ventilation device for ensuring safe driving.
19
0
Share

What are the BMW car series?

BMW car series include 1, 2, 3, 4, 5, 6, 7, i, M, X, and Z series. The following is relevant information about BMW: 1. Introduction to BMW: BMW, the full Chinese name being Bavarian Motor Works Co., Ltd., is a German luxury car brand. BMW was founded on March 7, 1916. The predecessor of BMW was an aircraft factory, initially renowned for manufacturing streamlined biplane reconnaissance aircraft. The predecessor company was named BFW, and its founder was Gustan-Otto. 2. The meaning of the BMW logo: B.M.W. stands for Bavarian Motor Works, and the colors and combination of the logo are derived from the state emblem of Bavaria, where BMW is located. The blue and white pattern is used to remind people of BMW's pure Bavarian heritage.
20
4
Share
Cookie
Cookie Settings
© 2025 Servanan International Pte. Ltd.