5 Step Guide To Detailing An Engine Bay

5 steps to detailing an engine bay

Enthusiasts who like to display their vehicles at car events will be the first to say that a smart, clean engine bay adds another layer to the pleasure of pride in appearance. Most daily drivers on the other hand, scarcely see their engine from one service to another, even if they spend time detailing the exterior.

Well there are some very good reasons to give the engine bay as much attention as the paintwork, so why not make it a part of your detailing regime?

Why Detail Your Engine Bay

Routine engine maintenance jobs, checking the fluid levels and the like are made much easier if the engine is clean. The area under the bonnet is largely open to the road and can get very dirty, very quickly, while also accumulating leaves and other debris. This in turn can lead to the degradation of exposed components. A clean engine bay makes it easier to spot leaks, damage as well as signs of wear and tear.

When You Should Detail Your Engine Bay

This important area should not be overlooked. It is best practice to clean under the bonnet every three to six months, depending upon usage and conditions. It is, after all, the heart of the car and it pays to keep it healthy. The first time cleaning it might be hard work, but subsequently that effort will make life easier thereafter. As the engine can be particularly dirty it might be best to have designated wash media that you keep separate specifically to clean the engine so as not to cross-contaminate and spread any dirt and grease around the rest of the vehicle.

What you will need

As with any maintenance job it is important to be prepared and have everything needed at hand. Ensuring you wear personal protection equipment to protect you from contaminants and product fumes, you will need:

• Degreaser or All-Purpose Cleaner (APC)
• Various detailing brushes, ideally with long handles
• Pressure washer or garden hose pipe
• Microfibre drying towel
• Ceramic Trim Dressing (suitable for high temperatures)
• Plastic bags to protect exposed electrical components and sensitive areas.

Preparing Your Engine Bay For Cleaning

Make sure the engine is off and cool to the touch before you make a start. Anyone who has had an engine burn will tell you that this is sage advice.

Clear away any loose surface dust and rubbish like accumulated leaves that rot and can block under-bonnet rain channels.

Although most modern engines have the plastic covering to make them waterproof, it does not harm taking the time to see if there are any exposed electrical components or sensitive areas that you need to cover. This is where the plastic bags come in handy.

We recommend starting the detail with the engine bay, that means you aren’t worried about dirt or product being sprayed over the other panels as this will be dealt with when you move onto the paintwork.

How To Clean The Engine Bay

Step 1: Initial Rinse

Start by giving the engine bay a rinse using your power washer or garden hose. This will remove any loose surface dirt as well as ensure the engine is cool before introducing products.

Top Tip: Keep the pressure washer high and at a safe distance from the engine, this is to avoid unnecessary pressure being put on the engine parts.

Step 2: Apply product and agitate

Use a degreaser or APC to clean the engine. If you are using degreaser, take extra care when applying, ensuring it doesn’t get on the exterior paintwork where it will likely strip away any previously applied wax or ceramic coating. It’s best to exercise on the side of caution.

Spray the product on and allow a short dwell time, this will allow the product to work and break down the dirt. Take a detail brush and work the product into the surfaces, don’t forget to get the sides of the plastic covers. Some areas can be inaccessible which is why a long-handled brush comes in useful. You may wish to have wheel barrel brushes that you use specifically for cleaning the engine. After all, just because you can’t see it doesn’t mean it does not need cleaning.

Step 3: Rinse

Once you have completed the whole engine bay, give it a rinse, following the same principle as the initial rinse, not focusing the water pressure in one specific area.

Depending on the condition of the engine you may need to repeat the process to achieve a standard you are happy with. Remember the first detail is always going to be the worst.

Once you are satisfied with the job, give the engine bay a final rinse before moving on.

Step 4: Drying your engine bay after cleaning

You have a few options here, you can either let the engine bay air dry, alternatively you can use a microfibre drying towel to soak up the majority of any standing water. Remember to remove any covering you used at this stage.

Another drying method is compressed air, this will allow you to remove much more water from all the nooks and tight areas that otherwise would be missed as a towel cannot reach between engine parts.

Step 5: Dressing rubbers & plastics

At any ‘show and shine’ motor events, the engine bays are often as smart as the exterior paintwork. That’s because the owners have gone the extra distance and used a dressing to make the components stand out, giving the whole a uniform appearance. Make sure to use a product that is designed for the job, in that it can withstand high under-bonnet temperatures.

Any painted surface might benefit from a Spray Sealant, as wax alone won’t do as the area will be too hot. To shine up the plastics and hoses you can use a good quality rubber/vinyl protection. This will help keep them subtle and avoid cracking. Finish off with a good buff-up with a microfibre cloth. Stand back and admire your handiwork.

In Conclusion

Detailing an engine bay is not a complicated task. For an older or well used car, initially it will be more arduous and might need extra cleaning but once done, in future regular cleaning will be much quicker. It will also make working on the engine a cleaner and more pleasant experience. Certainly, your local servicing engineer will thank you.