WD-40 as Starting Fluid: A Quick Solution for Engine Troubles

Are you planning to use WD-40 as starting fluid in your car? You should read this article before you go ahead!

WD-40 is a versatile product known for its numerous applications, including its use as a lubricant, rust preventative, and cleaner.

One debate among car enthusiasts and professionals is whether or not WD-40 can be used as a starting fluid. This article aims to shed light on this topic in a simple and informative manner.

While traditional starting fluids, which mainly contain ether, are designed to provide optimal conditions for ignition by drying out spark plugs, WD-40 is not specifically engineered for this purpose.

Nevertheless, it’s flammability and other properties can make it a makeshift substitute for starting fluid in some situations.

Wd-40 as Starting Fluid


WD-40 as a Starting Fluid

Properties of WD-40

WD-40 is a versatile lubricant, primarily used for its water-displacing, rust-preventing, and cleaning properties.

Its main ingredients are aliphatic hydrocarbons, petroleum-based oil, and carbon dioxide as a propellant.

While it is not specifically designed for use as a starting fluid, it does have some attributes that make it a potential substitute.

Pros and Cons


  • Ignition support: WD-40 can act as a starting fluid due to its flammability, helping with internal combustion in engines to start burning fuel.
  • Oil film preservation: Unlike traditional starting fluids that contain ether, WD-40 does not strip away the protective oil film from engine cylinders, which is crucial for engine health.


  • Potential engine damage: As WD-40 is not specifically designed to be a starting fluid, using it as such can cause other issues that may harm your engine.
  • Less effective than ether: Traditional starting fluids containing ether are more effective at drying out spark plugs, providing optimal ignition conditions for engines.

While WD-40 can function as a starting fluid in certain situations, it is not explicitly designed for this purpose.

The potential engine damage and reduced effectiveness compared to ether-based starting fluids may outweigh the benefits.

Comparison with Other Starting Fluids

Ether-Based Fluids

Ether-based starting fluids are known for their high volatility and effectiveness in cold conditions. However, they lack lubrication, which can lead to increased wear on engine components.

On the other hand, WD-40 contains some lubricating properties, making it a gentler option for starting engines.

  • Flammability: Both ether-based fluids and WD-40 are flammable, but WD-40’s propellant is less explosive.
  • Safety: Ether-based fluids can be harmful to 2-stroke engines due to the lack of lubrication, while WD-40 is a safer alternative.

Propane-Based Fluids

Propane-based starting fluids can also be used for igniting engines, especially in 2-stroke motors. In fact, WD-40 used to utilize propane as a propellant before transitioning to CO2.

  • Flammability: Both propane-based fluids and WD-40 are flammable; however, the ignition potential of WD-40 with CO2 propellant is lower than propane-based fluids.
  • Lubrication: WD-40 has an advantage over propane-based fluids due to its lubricating properties, which can help protect engine components from wear.

In summary, WD-40 can be a viable alternative to other starting fluids due to its lubricating benefits and flammability characteristics.

Wd 40 as Starting Fluid


Application and Safety Considerations

Proper Use of WD-40 as Starting Fluid

To use WD-40 as a starting fluid, follow these steps:

  1. Locate the air intake of your vehicle’s engine.
  2. Remove the air filter to get better access.
  3. Spray a small amount of WD-40 into the air intake.
  4. Quickly attempt to start the engine.

WD-40 acts as a water displacement agent, which could help remove moisture and improve combustion in the cylinders. However, it’s important to note that WD-40 is not specifically designed as a starting fluid.

Potential Risks and Hazards

  • Corrosion: Prolonged use of WD-40 on spark plugs can cause corrosion as it’s not a dedicated spark plug lubricant.
  • Volatile: WD-40’s propellant is highly volatile, increasing the potential for combustion-related issues or even engine fires if mishandled.
  • Gasoline dilution: Overuse of WD-40 may lead to gasoline dilution in the engine oil, reducing lubrication and causing possible damage.

When starting your vehicle, prefer using designated starting fluids over WD-40, as they pose fewer risks and are specifically designed for that purpose.

Alternative Solutions for Cold Weather Starts

Manual Methods

One manual method involves using a hairdryer or heat gun to warm your engine. This can help evaporate moisture and make it easier to start in cold weather. However, be careful not to overheat any parts.

Another option is to bring your battery inside overnight to warm up. Cold weather can cause reduced battery capacity, making it difficult to start your engine 1. By warming it up, you can improve its performance.

Specialized Products

There are several specialized products designed for cold weather starts. These include carb cleaners, which can help clean your carburetors and improve their efficiency.

Carburetors regulate the flow of fuel into the engine and can cause serious issues if misaligned or dirty.

If you’re having issues with ignition distributors, spraying a small amount of carb cleaner can help get rid of moisture. This will allow the spark plug to ignite and start your engine more effectively.

Another specialist product is starting fluid or engine starter. These are highly flammable spray cans, which can be used to aid in starting engines in cold weather.

Although WD-40 can work as a starting fluid, manufacturers recommend against it due to potential damage to your engine. Always make sure to follow the instructions on any specialized products you use.

Expert Advice and Additional Resources

Mechanic Tips

  • Mechanics recommend using traditional starting fluids instead of WD-40 to prevent engine damage.
  • Ignition systems can benefit from using carburetor cleaner or other similar products designed for the purpose.
  • WD-40, a penetrating oil, may leave unwanted residue, negatively affecting moving parts in motors.
  • Ensure a sufficient fuel supply and good compression for smooth engine starts in vehicles and boats alike.
Wd 40 as Starting Fluid


Best Practices for Using WD-40 as a Starting Fluid

When considering the use of WD-40 as a starting fluid, it is important to follow best practices to ensure safety and optimize its effectiveness.

While WD-40 is not specifically designed for this purpose, it can serve as a makeshift substitute in certain situations. Here are some guidelines to keep in mind:

Limited Application: Use WD-40 as a starting fluid only when necessary and as a temporary solution. It is not recommended for regular or prolonged use, as it may have adverse effects on engine components.

Apply a Small Quantity: Apply a small amount of WD-40 into the air intake of the engine. A short burst or a few sprays are generally sufficient. Avoid excessive application, as it can lead to undesirable outcomes such as gasoline dilution in the engine oil.

Quick Engine Start: After applying WD-40 to the air intake, make an immediate attempt to start the engine. The goal is to take advantage of WD-40’s flammability to aid in the ignition process. Delaying the start may reduce the effectiveness of WD-40 as a starting fluid.

Proper Ventilation: Ensure that the area where the application is performed is well-ventilated to minimize the concentration of WD-40 fumes. This is particularly important due to the highly flammable nature of WD-40’s propellant.

Safety Precautions: Handle WD-40 with caution, taking necessary safety measures. Keep it away from open flames, sparks, and sources of ignition to prevent accidents or fires. Store WD-40 in a cool and dry place, away from heat or direct sunlight.


The use of WD-40 as a starting fluid can be a temporary solution in certain situations where traditional starting fluids are not readily available.

While WD-40 possesses flammable properties that can aid in engine ignition, it is important to exercise caution and follow best practices to ensure safety and minimize potential risks.

After all, WD-40 is not specifically designed for use as a starting fluid and may have adverse effects on engine components if used improperly or for prolonged periods.

Therefore, it is recommended to rely on designated starting fluids that are specifically formulated for engine ignition.

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Sean Mendez

Hi, I am Sean, a self-confessed petrolhead. I live in Boise, Idaho with a busy family of four and our energetic Labrador retriever. Thank you for visiting my website. You can find my email on the contact page.

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