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How to Remove Water from Your Car/Bike Fuel Tank?

Having petrol mixed with water in your vehicle's fuel tank is a problem that can lead to various issues if left unchecked. Engine performance will suffer from this contamination, leading to rust formation and degrading efficiency.
Now, there can be a plethora of reasons that can lead to water entering the petrol tank, some of which are not even in your hand. However, you can know the solutions and prevention methods, reducing the chances of damage to your vehicle.
Read on to discover the symptoms of water presence in a fuel tank, problems, solutions, prevention methods and more.
Table of Contents
How to Check for Water Presence in a Fuel Tank?
If water enters the fuel tank of your bike or car, you may experience problems with acceleration, ignition, or sudden stalling. Furthermore, if these issues persist, you should visit a mechanic to check for water in the petrol tank.
You can check for water in the fuel tank yourself by following the methods given below:
1. Smell the Fuel
A fuel tank with water may produce an unpleasant odour.
2. Check the Colour of the Fuel
If the fuel looks darker than usual, it may contain water.
3. Look for Microbial Growth
Water can cause bacteria and fungi to grow inside the tank.
4. Use a Water-detecting Paste
Apply a water-finding paste on a dipstick and insert it into the tank. If the paste changes colour, water is present.
How Does the Water Enter the Fuel Tank of Your Car or Bike?
The following are the different ways through which water can enter the fuel tank of your car or bike:
Poor Sealing and Maintenance
A damaged or improperly sealed fuel tank allows water to seep in.
Rainwater Contamination
Water can enter the tank if the fuel cap is loose or faulty, especially during rain.
Condensation in Cold Weather
Lower temperatures cause moisture to accumulate inside the tank.
Moisture Buildup
Water can mix with petrol, diesel, or oil due to prolonged exposure to humidity.
Biofuel Absorption
Biofuels attract water from the air as they tend to absorb moisture.
What are the Problems Due to the Presence of Water in Fuel Tanks?
Water in the fuel tank directly impacts your vehicle’s performance and damages critical components. Here are some common problems your car or bike may experience:
Fuel Injector Malfunction
Modern vehicles use injectors to regulate fuel flow into the combustion chamber, replacing older carburettors. These injectors have tiny pores designed to spray fuel efficiently. However, water is denser than fuel, so it does not spray as effectively. This puts extra strain on the injector, leading to performance issues.
Rust Formation
Since fuel and water do not mix, the water gradually accumulates at the bottom of the tank. If left unchecked, rusting occurs, especially in tanks with ridges or edges where moisture gets trapped.
Power Surges and Engine Failure
Water in the fuel can cause sudden power fluctuations. When you start the engine, the vehicle might jerk forward unexpectedly. In severe cases, excessive water in diesel engines can prevent it from starting altogether.
Steam Emission
If you drive through waterlogged roads, you may notice steam escaping from the exhaust after some time. This occurs due to water contamination in the fuel system.
Fuel Pump Damage
The fuel pump transfers fuel from the tank to the engine while also aiding in cooling and lubrication. When water enters the system, it interferes with these functions. Additionally, rust and injector problems can further impact the fuel pump’s efficiency.
Lubrication Issues
If water mixes with engine oil, it affects the lubrication process. The higher the water content, the greater the damage to engine components, leading to friction and wear.
What are the Different Symptoms of Water in Fuel Tanks?
If your vehicle has water in the fuel tank, you may notice these warning signs:
Reduced Power and Mileage
Water in the fuel tank affects the combustion process, lowering the engine’s efficiency. This leads to decreased power and mileage in both cars and bikes. Ignoring this issue can make the problem worse.
Engine Stalling
Vehicles with water-contaminated fuel tanks often experience engine stalling. This can happen while driving or trying to start the car or bike. Water disrupts combustion and compression, causing the engine to stop suddenly.
Jerky Movements
If water is in the fuel tank, your car or bike may shake while accelerating. You might need to apply more throttle as the vehicle struggles to maintain power.
Steam Emission
The presence of water in the fuel tank can cause steam to escape from the exhaust pipe as it evaporates.
Water Droplets from Exhaust
Sometimes, water might drip from the exhaust due to condensation inside the system.
Different Solutions to Remove Water from the Fuel Tank
If you are wondering how to separate water from petrol, a mechanic might attempt to fix the problem using different methods, which are mentioned below:
Draining and Refilling
Draining the fuel tank while refilling it with premium fuel remains a quick solution to resolve this issue. However, the elimination process of water through this method tends to be expensive.
Replacing the Fuel Filter
The fuel filter is designed to block water from reaching the engine. However, if water accumulates in the filter, it can cause damage and lead to malfunctions. In such cases, replacing the fuel filter can help restore proper functionality.
Using Rubbing Alcohol
Rubbing alcohol is an effective solution for removing water from fuel tank reservoirs. When it reaches the bottom of the fuel tank, it absorbs the water and allows it to enter the engine for combustion.
Applying Fuel Additives
Mechanics often use fuel additives as a solution to dilute water present in the fuel tank. Typically, methanol-based additives are used for this purpose. However, this method is only effective when the water contamination is minimal.
Get Expert Assistance
If water enters the fuel tank, it can seriously damage your vehicle. To prevent further damage, it is best to consult an expert who can safely remove the water and fix the problem.
Tips to Prevent Water from Entering the Fuel Tank
Keeping water out of your fuel tank is essential to maintaining your vehicle’s performance. Follow these simple tips to prevent water contamination:
Pick the Right Tank
Choose a fuel tank with a sloped bottom so that any water present collects in one place, making removing it easier.
Use High-Quality Seals
Invest in durable seals and gaskets to block water entry. Inspect them regularly and replace worn-out ones.
Select a Proper Location
Position the vehicle on a smooth horizontal surface where rainwater and runoff cannot reach it. Also, consider parking your car or bike in a covered area to reduce the chances of water damage.
Inspect Regularly
Conduct routine checks to spot cracks, corrosion, or loose seals that might let water in.
Ensure Proper Ventilation
Good ventilation helps control moisture levels inside the tank, reducing condensation and water buildup.
Keep Fill Points Covered
Always close fuel caps securely to prevent rainwater from entering while refuelling.
Follow Regular Maintenance
Clean the tank periodically and test the fuel quality to detect and fix water contamination issues before they cause damage.
Install Water Sensors
Consider using water sensors or alarms that alert you if water gets into the tank, allowing you to act quickly.
What are the Insurance Coverage and Support Options for Vehicle Owners?
Water-induced damage can cause serious issues in a vehicle, leading to costly repairs. However, a comprehensive bike insurance or car insurance plan can provide coverage for water damage due to heavy rains or floods. They also provide benefits like:
Extensive Coverage
It covers damages from accidents, natural disasters, theft, and third-party liabilities.
Financial Protection
Saves you from heavy repair costs due to unexpected incidents.
Add-On Benefits
Options like roadside assistance, zero depreciation, and engine protection enhance insurance coverage.
Peace of Mind
Ensures you ride worry-free, knowing you are protected from unforeseen expenses.