How to Clean Engine Bay Safely With Steam

There’s more to keeping your car look its best than washing and waxing the exterior. It’s the little details that make the most significant impact, especially during car shows and events. 

In recent years, more people have been looking into getting their engine bay cleaned. However, there are many concerns regarding how to accomplish this without damaging the vehicle. Fortunately, steam cleaning is a viable option for this purpose.

Here’s how to clean an engine bay safely with steam.

Why Clean Your Engine Bay?

Cleaning your engine bay is more than just an aesthetic decision that makes your car look immaculate when you peek under the hood. When done correctly, detailing your engine can help prolong the lifespan of your vehicle.

Cleaning your engine bay to remove dirt and grease helps your engine run a little cooler. While it may not make a huge impact, allowing your vehicle to work smarter, not harder, can help prolong its lifespan and reduce maintenance needs.

Another benefit to cleaning your engine bay is the chance to identify any small maintenance issues that need to be addressed before they become a big problem. A build-up of grease and grime can also degrade wires and connections over time. 

While car interior cleaning is important at any time, cleaning the engine is also a must before putting a car up for sale. This simple chore will attract more potential buyers and get you closer to your asking price.

How Does Steam Cleaning Work?

Steam cleaning is an innovative alternative to water application. These devices heat water past the boiling point and force the steam through the nozzle for effective cleaning without the same level of pressure. The mist lifts debris and rinses it away with minimal contact.

Many high-quality steamers have various settings that allow you to control the vapor wetness and pressure. If you are taking a DIY approach to cleaning your engine bay, use a steamer that’s specifically designed for this task to avoid damaging your car.

Understanding the Risks of Water

One of the main concerns with using a hose or pressure washer to clean the engine bay of your vehicle is the potential to damage sensitive electrical connections. This is one reason why it’s so important to use the right tools.

While most modern vehicles can withstand the spray from a garden hose, some older vehicles may be damaged. Vintage cars lack the same protective plastic components that many modern vehicles possess on the engine, for example. Furthermore, if there’s any degradation over time, the application of too much force can damage or remove an older cap or coating. 

If you have a modified or show car with aftermarket parts, you should also be cautious when washing the engine bay. There are a variety of filters and intakes that will get destroyed when sprayed with water. If you have any aftermarket parts or have had parts added by a third party, always use steam instead of water.

Those who choose to use a standard hose should stand back from the engine while spraying and use hot water and a toothbrush to detail the nooks and crannies. If you have any exposed wires or cracked caps, wrap them with plastic and tape to keep them dry.

How to Safely Steam Clean Your Engine Bay

Safely cleaning your engine bay requires the right combinations of tools and attention to detail. Here’s a step-by-step guide to safely steam clean your engine bay.

Determine the Necessity

First, determine whether it’s necessary to clean your engine right now. Keep in mind that there is too much of a good thing and that this part of your vehicle doesn’t require weekly cleaning. 

Cleaning your engine bay is a great seasonal maintenance chore. Schedule time to clean the engine after the hot, dry, dusty summer months or snowy, slushy winter months. You may decide to do a thorough cleaning twice annually with a small sweep in between.

Choose the Right Timing

Timing is everything when cleaning your engine. Ideally, you’ll choose a period where your vehicle can be inactive for the entire day. You want to ensure that the engine is cooled completely before starting the process and allow ample time for it to dry before using it again.

Give yourself a buffer of a few hours before and after driving your vehicle after the steam cleaning. This strategy will give you ample time to give your car the attention it deserves. You can also pair this chore with interior cleaning, allowing the engine to dry while you move to the inside of the car.

Start with a Sweep

Before you apply any products or moisture, start with a quick sweep to remove loose debris. Use a brush to dust off the engine block, removing dirt, leaves, etc. This step is also an excellent opportunity to identify anything that should be covered (loose caps, etc.) before you proceed with the cleaning.

Use a Degreaser

Next, apply a degreasing solution and let it soak in. If you have a professional steamer, it may come with a detergent additive, rendering this step unnecessary. However, if you have tough spots with a lot of build-ups or a simple steamer, you’ll want a strong product.

Be sure to purchase a non-petroleum, engine-safe degreaser from an auto shop if you’re taking the DIY route. It’s crucial to ensure the product you use won’t cause more harm than good.

Apply the Steam

Once you’ve let the degreaser soak in, it’s time to apply the steam. Carefully rinse off the degreaser without hitting caps and wires, even if you’ve wrapped them first. Using a wetter steam setting will make this process more effective.

If you notice some tough spots after the rinse, reapply degreaser and repeat as needed. You may determine that a toothbrush or scrubbing pad is required for small areas with lots of grease and dirt. It’s better to get your hands dirty and spot clean these areas, rather than try to use a sprayer or steamer. 

Allow It to Dry

Once you’ve finished cleaning the engine bay to your liking, give it time to dry with the hood up. You can use compressed air or a leaf blower to speed up the process. Again, be mindful of aiming it at any exposed wires or caps. 

It’s essential to let the engine return to the ambient temperature before operating, which is also why a two-hour rest period after cleaning is important. Failure to let your engine bay dry entirely could cause problems down the road. The heat from your engine could react with the products you’ve applied and create more of a mess or degrade some of the materials used under the hood.

Adding Other Products

After the engine is dry, you can apply wax or engine dressing to bring out the metal and plastic shine. This step is entirely optional but makes a big impact when taking photos to post your vehicle for sale or when heading to a car show.

Confirm that the products you’re using are appropriate for the materials on your engine block. Plastic panels and metal components will have different needs. Choose an engine dressing that’s deemed safe for your vehicle and apply it evenly for a consistent gleam.

Final Thoughts

Patience is a virtue when cleaning the engine bay of your car with steam. Being meticulous and thorough will allow you to get the job done without risking the safety of your vehicle. If you’re ever in doubt about the tools you have on hand or which parts of your car are exposed, work with a professional detailer.

Will Hopstetter
Will is an automotive market enthusiast living in the United Kingdom. He holds a diverse background in automotive and enjoys utilizing that to produce insights into the inner workings of the industry.