How To Clean Car Engine with WD40 – Step-by-step Guide!

Using WD40 for cleaning grease from vehicle engine is quite simple, effective, and low cost solution. It simple required to warmup your engine, disconnect battery, safeguard car electrical connection, applying WD40, removing grease with water & clean cloth, then simply reconnecting the battery after the engine surface dry.

Getting to know all the good praises regarding WD40, you might be wondering‘ can I clean my car engine with WD40’. Well, why not? It’s a pretty effective solution that can help loosen the grease and old grimes.

Cleaning grease from engine using WD40 is quite simple and does not take much time. So we have develop a complete guide on how to clean car engine with WD40 step by step today.

How To Clean Car Engine with WD40.

Using WD40 on car engine is super simple if you know the basic procedure. This usually take 30 minute to an hour. Here are the 6 steps Guide on how to cleaning your car engine. 

  •  Idling of car engine
  • Removal and securing of car battery
  • Securing all other electrical components
  • Applying WD-40
  • Clean the Engine surface
  • Drying process
  • Reconnect the car battery & its all done
Steps To Clean Car Engine with WD40 Infographic

1. Idle the Car for A Couple of Minutes

Start the car engine only and gently trigger the brake pedal using your foot. Do this for 5 – 10 minutes. This will help the car to get hot which helps in cleaning the stubborn dirt and grease easily. Turn off the ignition. 

2. Disconnect the Negative & Positive Battery

After warming the car, open the hood (bonnet) and secure it with the stud. Locate the battery area as you need to remove and secure the battery first. 

Take out the negative terminal (black cap) of the battery after wearing the safety gloves and rubber slipper. To find the negative terminal, look for the small minus sign near or on the battery. 

Detach the positive terminal (red cap) of the battery. You’ll find it by looking at the plus sign near or on the battery.

Protect the negative and positive terminals using plastic caps like the MCIGICM Wire Nuts to avoid electric shock and protect the open wire. Remove the stud support and close the car hood.

S3. Cover the Electrical Components

Take a big plastic wrap to cover the electrical components. Apply the duct tape to keep the plastic wrap in the right place.  Its very important to cover all electrical components before applying WD-40 as it can easily damage any electrical connection or circuit.

4. Apply the WD40 To the Car Engine

Grab a lint-free clean cloth and wipe out dust. 

Spray the WD40 spray (if you are looking for one, try the WD-40 110071) on the greasy areas. depending on the current condition of the engine you may need to use a small brush to remove grease.

Remove the grease and all the waste using water and clean cloth. You need to rinse all the grease, waste and WD-40 from the engine.

5. Let the Engine Dry

After removing all the grease and WD-40 from engine, you need to wait for few minutes (its a lot depends on the weather and surrounding). Do not connect any electrical wire or try to start engine as it might short circuit the entire setup or do any other harm.

6. Connect the Negative & Positive Battery.

After drying is done reconnect the battery and for that first remove the duct tape and plastic wrap. Then take out the wire caps and insert the negative terminal into the car battery (minus sign). Do the same thing to insert the positive terminal on the car battery (plus sign).

Close the hood, Its all done.

Frequently Asked Questions

1. What can I use to clean oil off my engine?

You can use any penetrating oil like the WD40 or try applying the degreaser with a brush to wipe off the oily surface from the engine bay. Gently remove the dirt with water and clean cloth. It will take 30 to 60 minutes at max to complete the task. 

2. Is it safe to spray your engine with water?

Yup, it is! You spray water on the engine to keep it clean from dirt (as the majority of the latest car allow that). However, do not use water on electrical parts like alternators, air intake, and sensors.

3. Will WD-40 damage an engine?

The WD40 usually doesn’t damage the engine. However, you can’t use this on a non-greasy or clean engine as it contains strong chemical which react things like pain or metallic surface. Use the WD40 only on the greasy and old engines.

Ending Notes

Maintaining a car engine keeping it in good shape is something anyone should do. You might need to take care of it once in 6 months or 6,000 miles using a strong penetrating oil like WD40. 

As you now know how to clean car engine with WD40, hope you’ll continue to upkeep and avoid facing the grease and dirt causing issues under the hood. 

Be sure to follow the directions without skipping any part. And wear the safety equipment before starting. Hope the shared guidelines help you to cleanse the engine well. 

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William Baldwin

This Is William Baldwin, The Founder & Managing Editor of this website. Me and my team share automotive tips, tricks, and news

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Talha Atta

Talha Atta, a Mechanical Engineer and experienced technical content writer and editor at with a passion for the automotive industry.