How to clean your engine bay

Cleaning your engine bay might seem like one of those "I’ll do it later" tasks, but keeping it tidy is actually one of the best things you can do for your car.

At Carma, we believe a clean car isn’t just about looking good on the outside. It’s about knowing everything under the hood is in equally great shape. A clean engine bay makes it much easier for you (or your mechanic) to spot a potential oil leak before it becomes a major headache. It also makes routine checks and simple maintenance tasks, like refilling your windscreen wiper fluid, cleaner and easier.

If you’ve been putting it off because it feels daunting, don’t sweat it. We’ve put together this simple guide to help you give your engine the spa day it deserves.

What you’ll need:

• Car wash detergent & degreaser: A good quality car soap for the light stuff and a dedicated engine degreaser for any stubborn grime.
• Debris busters:: A vacuum, leaf blower, air compressor or just a garden glove and your hands to get rid of any leaves or twigs.
• Low-pressure water: A garden hose on the "mist" shower setting. (Skip the high-pressure washer here, we want to clean, not blast water into places it doesn't belong!)
• Brushes: A mix of soft-bristled brushes (even an old paintbrush or toothbrush) to reach those tricky nooks and crannies.
• Microfibre towels: You’ll need a few of these for wiping and drying.
• Safety gear: Grab some gloves and eye protection, degreasers can be pretty potent.

Your step by step guide

1. The prep phase

Before you start, make sure the engine is completely cool. Spraying cold water onto a hot engine block is a recipe for disaster (and potentially cracked components).

2. Clear the debris

Using your vacuum or blower, clear out any loose leaves or dirt. Using your hands with gloves also works fine! This will provide protection from sharp things and spiders hiding in crevices. It’s much easier to remove debris while it’s dry. If you wait until it gets wet, it can turn into a muddy paste that’s a nightmare to clean up.

3. Start from the top

Start with the underside of the bonnet. Cleaning from the top down ensures that any grease or dirty water doesn’t drip onto sections you’ve already scrubbed. Apply some degreaser where needed and let it work its magic for a few minutes, but don't let it dry! Then give it a gentle scrub with a brush and a light rinse.

4. The main event

Now for the engine itself. Spray your degreaser onto the dirtiest areas.

• For light dust: Use your soapy car wash.
• For heavy oil: Let the degreaser sit for 2-5 minutes.
• Scrub gently: Use your brushes to agitate the gunk. You’re not scrubbing a BBQ; a gentle touch with the right chemicals will do most of the work for you.
• Rinse with care: Use a gentle stream of water to wash the grime away. Repeat if necessary.

5. Dry thoroughly

Use your microfibre towels to soak up any obvious water. If you have an air compressor or blower, use it to push water out of any crevices. Finally, start the engine and let it run for about 10 minutes. The heat from the engine will help evaporate any lingering moisture in hard-to-reach spots.

Expert tips for a better clean

• Mind the drains: Be mindful of where your runoff goes. If your engine is particularly greasy, try to avoid letting the residue wash directly into stormwater drains.
• The 3-month rule: Making this part of your regular car maintenance tips routine every few months means you’ll never have to deal with heavy caked-on grime again.
• Add a finish: For that "showroom" look, you can apply a water-based plastic protectant to the hoses and plastic covers once dry.

Cleaning your engine bay isn’t just for car enthusiasts, it’s a smart move for any owner who wants to keep their vehicle in top shape. By following these steps, you’re not only making your car look brand new under the hood, but you're also helping ensure its longevity and reliability. If you’re looking to give the rest of your car some love, check out our guide on how to wash your car like a pro for tips on getting a streak-free finish.