Overview
We spend countless hours detailing the interior and exterior of our cars, but how many people give the needed attention inside the engine bay? Having your engine bay properly detailed not only looks great, but it also helps fight potential corrosion as well. With a few simple tools and supplies, you too can keep the area under the hood looking like it was professionally detailed.
Precautions
I’ve spoken with a tremendous amount of people who don’t detail the engine bay simply because they’re concerned about damaging the car. It only requires a few preventative measures along with some common sense, and you can clean your engine compartment without worry. The biggest concern is that water will short out electrical connections. In most modern cars, key electrical components and housings are tightly sealed from the elements of daily driving. As long as you’re not directing a strong stream of water (or a pressure washer at close range) directly into these components, you will be fine.
Precautionary Tips:
- If the air intake opening is directly in sight, then you can either stuff it with a towel, or cover it up with plastic wrap and a rubber band (don’t forget to remove it when you’re done!).
- If you have an aftermarket intake system with an exposed air filter, then cover it up with a plastic bag and secure it with a rubber band.
- If you have a fully exposed alternator you can either cover it with plastic wrap, or even better yet use aluminum foil. The foil is easier to mold and fit around the alternator without having to tightly secure it.
- Use the wide spray pattern on your hose nozzle as opposed to a strong stream. You only need a light rinsing as the cleaners and brushes will be doing all of the work.
- Working on a warm engine is fine, but if it’s hot, then let it cool for a while.
Items Needed
- An all purpose cleaner, such as P21S Total Auto Wash or Chemical Guys Grime Reaper if you require heavy degreasing
- A brush like the Mini E-Z Detail Brush
- A sponge or wash mitt
- Protectants and dressings, such as 303 Aerospace Protectant and Chemical Guys Fade 2 Black
- Microfiber Towels
How-To Detail Your Engine Bay
This engine bay has just gotten through a rough Midwest winter, and everything is covered in grime.
First start out by completely covering all surfaces (including the under side of the hood itself) with P21S Total Auto Wash. This is a gentle cleaner that is safe to use on virtually all areas.
Now that everything is covered, let it dwell for a few minutes so it can break down the grime.
Using your Mini E-Z Detail Brush, agitate the heavier buildup. You can use your sponge or mitt for cleaning the larger flat surfaces.
As you can see, the Mini E-Z Detail brush does a great job of getting into all of the hard to reach areas.
After you have brushed and wiped everything down, lightly rinse it all off with a gentle spray of water. Start with the underside of the hood first, and then work your way into the engine compartment. There are plenty of places for dirt and grime to hide, so be thorough with your rinse.
If you have a Metro Vac & Blo or compressed air, use it to blow all of the standing water away. If not, then just use your MF towel to wipe it all down. For further drying, you can also start the engine and let it run for a few minutes.
Now it’s time to add the finishing touches to your engine compartment. Spray on 303 Aerospace Protectant to all plastic and rubber, and then wipe it down to reveal a matte finish that is not greasy or oily. This is a tremendous and versatile product that can be used on many areas of the car.
For hoses, wires, and other hard to reach rubber and plastic pieces I like to use Chemical Guys Fade 2 Black (this is also my go-to product for the wheel wells!)
All done! Now you have a much nicer looking engine bay that is clean, free from potentially corrosive materials, and protected from the elements.
Engine Bay Before and After Photos
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If you have any additional comments or questions, please submit your reply in the comment box below.
Awesome write up on detailing. I plan on starting my own detail business and you basically gave me the blueprint to the whole operation. Thank you for such a detailed outline.
Excellent job! Would using this method the same way be safe for an 07 z06? Outside of the alternator and filter, there seems to be a lot more exposed electrical parts in the z06 compared to this Honda engine. It could only *appear* that way…
Thanks
Yep, pretty much the same…just cover the mentioned components. I cleaned the engine bay on both a Z06 and a regular C6 Corvette last year and all was good. You can even see in the engine photo of the C6 article where the alternator is the only item covered.
What about cleaning the engine bay for a lexus 1994 ls 400 whats the process?
Mervin,
Just follow the basic guidelines in the article and you should be fine. If an item looks questionable for getting wet, then just cover it up with plastic or foil.
Good luck!
Todd
Could you spray Fade 2 Black to a microfiber towel or foam applicator pad, then apply? My concern is over spray to objects you don’t want the product on. Also, I would advise against using foil in the engine bay. Reason being that it conducts electricity. In a perfect world there would not be any terminals/wires that have a positive potential (positive). 98% of the metal in the engine bay is a ground (negative). If the foil were to connect the two by simply touching both at the same time, you could very likely have a car fire on your hands. So I say to use plastic bags and 3M blue painters tape to be safe.
Yes you could spray Fade 2 Black onto an applicator and apply it that way if you wanted to avoid overspray…
Some advice please.
My Mom’s 74 Mustang II (30,000 original miles) just took Bronze in the unrestored original class. Of the the 78 points deduducted there was a 25 point mandatory deduction for the engine being oversprayed.
The detailer spray painted the engine as favor to us. This happened about a year ago. The has all it’s original white paint, spark plugs and plug wires. What would be the best way to remove the spray paint and not harm the original. Believe me they we find almost any flaw, lost one point for a dirty brake pedal and one point for a dinged step plate on the driver’s side door sill.
Thanks
Bob,
Without actually having the car right in front of me, I can’t give exact advice on how to approach this because there are simply too many variables. In some cases detailing clay will remove it, but it depends on what surface it’s on. If the paint is on rubber surfaces, you’ll need to try one method, but if it’s on other painted parts you may have to try another. If you need to do a chemical approach, it’s questionable about how it will affect the original paint underneath. Unfortunately I’m unable to guarantee either results or risk in a situation like this one.
You may want to seek a local restoration professional on this one simply because of the risk factor involved.
I hope this helps.
Todd
Thanks for your reply.
Just engine parts & radiator that were originally black were painted.
Most likely, it is best just to leave the paint.
We show the car just for fun. It is too bad, but things this happen.
If you do too well in unrestored original (two gold place finishes) your pushed into concours.
Then things really get serious, picking rocks out the tires, etc.
Now, it just hanging out meeting nice people.
Again, Thanks pardon the bad typing.
Bob
Todd
I want to detail the engine bay of my Audi A5 but frankly I’m very afraid. I have read all your articles but still not sure. Any particular suggestion for Audi A5?
Your comments are always appreciate it
Art
Art,
If you follow these instructions, you’ll be fine! Just be careful of the air intake, and only use a fine mist of water. Modern cars have their delicate electronics components sealed up…
THANK YOU!
Fine mist will rinse the TAW.
I have a good teacher and I will be very careful!!