Engine Compartment Washing
Thread Starter
Pro
Joined: Jun 2014
Posts: 705
Likes: 96
From: Ventura County CA
Engine Compartment Washing
My engine bay is dusty. Is there anything special I must do to clean it? Should I use any cleaners on it? Probably not pressure washing. Suggestions, warnings?
Le Mans Master
Joined: Aug 2015
Posts: 6,884
Likes: 2,887
From: Toronto
Ive never used water under pressure under the hood. Too many electrical components including the fuse box. Ive just used a damp microfiber towel and warm water. Not show car results but works pretty good.
Drifting
Joined: Sep 2019
Posts: 1,913
Likes: 1,957
From: Colo Spgs, CO
I'm sure you'll also have no problems with the method to which you appear to have been pre-disposed.
Thread Starter
Pro
Joined: Jun 2014
Posts: 705
Likes: 96
From: Ventura County CA
You're entitled to your opinion, but you asked. My experience with at least half-a-dozen vehicles over the past decade, including my C7Z, indicates your concern is unwarranted. I've had zero problems simply by staying away from high-pressure water and avoiding open electrical components (e.g., alternator).
I'm sure you'll also have no problems with the method to which you appear to have been pre-disposed.
I'm sure you'll also have no problems with the method to which you appear to have been pre-disposed.
Drifting
Joined: Mar 2022
Posts: 1,397
Likes: 801
From: Indiana
Just did mine the other day at the car wash. Drove straight there with a cold engine to minimize heat. Washed the car with he touchless wand as usual. popped the hood and sprayed soap all over the engine bay and let it sit while I rinsed the car, went back and rinsed the engine being careful not to keep the wand back enough the pressure was not an issue. dried off with my chamois as usual and it looks great. Wouldn't call it perfect, but looks 95%. The other 5% will take a few hours. Happy with the results.
Melting Slicks
Joined: Feb 2018
Posts: 2,177
Likes: 1,044
From: North Texas
Cold engine.
This step if the engine is really Dirty.
Hose end Dial-A-Sprayer set at 8oz filled with green Dawn detergent.
Spray entire engine, use a brush for the really bad areas.
If only dusty then:
Rinse off with water completely with hose end fan nozzle sprayer.
Leaf blower to remove the almost all the water but leave some behind.
Spray entire engine bay with Meguiars Hyper Dressing.
Let self dry for 3 -4 hours, the dressing is self leveling.
It will look better than new.
This step if the engine is really Dirty.
Hose end Dial-A-Sprayer set at 8oz filled with green Dawn detergent.
Spray entire engine, use a brush for the really bad areas.
If only dusty then:
Rinse off with water completely with hose end fan nozzle sprayer.
Leaf blower to remove the almost all the water but leave some behind.
Spray entire engine bay with Meguiars Hyper Dressing.
Let self dry for 3 -4 hours, the dressing is self leveling.
It will look better than new.
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Verdad Gallardo
Tech Contributor
Joined: Oct 1999
Posts: 41,058
Likes: 9,820
From: Charlotte, NC (formerly Endicott, NY)
I have been using the following procedure since the late 80s and it works well. I first start with a cold engine, open the hood and then soak the complete engine compartment with a 50/50 mixture of Simple Green/Water using a hand-pumped sprayer. I make sure everything in the engine compartment is dripping with the mixture. Once done I let it sit for about 10 minutes to soak into the dirt then use a garden hose with the sprayer set on a wide pattern and use it to rinse the engine compartment. I may use a narrow spray to get into nooks and crannies behind the wheel wells etc depending on what is behind them. After the engine compartment is completely rinsed I close the hood, start the engine and let it idle for about 25 minutes. This is usually long enough to evaporate all of the water in the engine compartment. Simple Green is a very effective biodegradable detergent and it does a great job of dissolving oil, caked-on dirt and dust. The cooling system hoses always have a sort of velvety feel/look to them after I do this.
Bill
Bill
Safety Car
Joined: Mar 2004
Posts: 4,048
Likes: 1,477
From: South Florida
Cold engine + pressure washer + simple green has been my go to for many years. As long as you don't shove the pressure washer up close on anything electrical or "sensitive" you won't hurt a thing. Keep the spray tip at least a foot away and don't do anything other than a real quick pass on electrical connections to rinse off the soap. Also, cover your intake filter if you don't have the stock box or an enclosed aftermarket intake box.
Then dry off what you can with a towel and let the car dry overnight, preferably with a fan blowing into the engine bay.
Then dry off what you can with a towel and let the car dry overnight, preferably with a fan blowing into the engine bay.
Melting Slicks
Joined: Feb 2018
Posts: 2,177
Likes: 1,044
From: North Texas
A lot of professionals use steam to clean the engine bays.
In aircraft they use safety solvent. I'll never forget that smell, how sweet.
In both instances they never use simple green and a water hose but it can work and has been used for years on cars.
Best friend that has buddies in aircraft maintenance and demonstrated two new products to him.
NOTE:
Aircraft quality chemicals.
Spray on cleaner, let it drain off until squeaky clean. The spray on the preserviant let air dry. Look as new from the factor.
He demonstrated it on my friends old dirty engine bay, really dirty. Took all of 5 minutes and after looked new in every way.
Only issue was that each chemical was ~$1K a gal 10 years ago. Also absolute no down side to these chemicals except the price and availability. They only sell to FBOs.
I myself I stick to green Dawn in a Dial a Spray sprayer ( if engine is really dirty if not then just hose off ), hose off gently, blow dry 80% spray entire engine bay with Hyper Dressing by Maguires.
Good as it gets ad looks like new.
In aircraft they use safety solvent. I'll never forget that smell, how sweet.
In both instances they never use simple green and a water hose but it can work and has been used for years on cars.
Best friend that has buddies in aircraft maintenance and demonstrated two new products to him.
NOTE:
Aircraft quality chemicals.
Spray on cleaner, let it drain off until squeaky clean. The spray on the preserviant let air dry. Look as new from the factor.
He demonstrated it on my friends old dirty engine bay, really dirty. Took all of 5 minutes and after looked new in every way.
Only issue was that each chemical was ~$1K a gal 10 years ago. Also absolute no down side to these chemicals except the price and availability. They only sell to FBOs.
I myself I stick to green Dawn in a Dial a Spray sprayer ( if engine is really dirty if not then just hose off ), hose off gently, blow dry 80% spray entire engine bay with Hyper Dressing by Maguires.
Good as it gets ad looks like new.
Last edited by Tinkertech; Jun 3, 2023 at 09:28 AM.
Safety Car
Joined: Mar 2004
Posts: 4,048
Likes: 1,477
From: South Florida
A lot of professionals use steam to clean the engine bays.
In aircraft they use safety solvent. I'll never forget that smell, how sweet.
In both instances they never use simple green and a water hose but it can work and has been used for years on cars.
Best friend that has buddies in aircraft maintenance and demonstrated two new products to him.
NOTE:
Aircraft quality chemicals.
Spray on cleaner, let it drain off until squeaky clean. The spray on the preserviant let air dry. Look as new from the factor.
He demonstrated it on my friends old dirty engine bay, really dirty. Took all of 5 minutes and after looked new in every way.
Only issue was that each chemical was ~$1K a gal 10 years ago. Also absolute no down side to these chemicals.
In aircraft they use safety solvent. I'll never forget that smell, how sweet.
In both instances they never use simple green and a water hose but it can work and has been used for years on cars.
Best friend that has buddies in aircraft maintenance and demonstrated two new products to him.
NOTE:
Aircraft quality chemicals.
Spray on cleaner, let it drain off until squeaky clean. The spray on the preserviant let air dry. Look as new from the factor.
He demonstrated it on my friends old dirty engine bay, really dirty. Took all of 5 minutes and after looked new in every way.
Only issue was that each chemical was ~$1K a gal 10 years ago. Also absolute no down side to these chemicals.
Yeah a water hose is a bad idea. The pressure washer sprays a lot less water. That is one of the reasons to use it.
3rd Gear
Joined: Jan 2018
Posts: 3
Likes: 1
Been doing the following procedure for all my cars, including my 2nd 2016 C7. I use a 1750 psi pressure washer to rinse the bay off, spray everything down with simple green(slightly diluted), wait a couple of minutes and then rinse everything down again. While the bay is still wet, I use Mequirs HyperDressing, 50/50 mix, and spray everything down under the hood. Close the hood, youre done? Let it dry overnight. Great results. I get compliments on the engine bay of all my vehicles. And, when it comes to simple green......................This is a quote from the Simple Green website:
"Is it safe to use Simple Green on aluminum?
Simple Green products have been successfully and safely used on aircraft, automotive, industrial and consumer aluminum items for over 20 years. However, caution and common sense must be used: Aluminum is a soft metal that easily corrodes with unprotected exposure to water. The aqueous-base and alkalinity of Simple Green or Crystal Simple Green can accelerate the corrosion process. Therefore, contact times of All Purpose Simple Green and Crystal Simple Green with unprotected or unpainted aluminum surfaces should be kept as brief as the job will allow - never for more than 10 minutes. Large cleaning jobs should be conducted in smaller-area stages to achieve lower contact time. Rinsing after cleaning should always be extremely thorough - paying special attention to flush out cracks and crevices to remove all Simple Green/Crystal Simple Green residues. Unfinished, uncoated or unpainted aluminum cleaned with Simple Green products should receive some sort of protectant after cleaning to prevent oxidation."
..
"Is it safe to use Simple Green on aluminum?
Simple Green products have been successfully and safely used on aircraft, automotive, industrial and consumer aluminum items for over 20 years. However, caution and common sense must be used: Aluminum is a soft metal that easily corrodes with unprotected exposure to water. The aqueous-base and alkalinity of Simple Green or Crystal Simple Green can accelerate the corrosion process. Therefore, contact times of All Purpose Simple Green and Crystal Simple Green with unprotected or unpainted aluminum surfaces should be kept as brief as the job will allow - never for more than 10 minutes. Large cleaning jobs should be conducted in smaller-area stages to achieve lower contact time. Rinsing after cleaning should always be extremely thorough - paying special attention to flush out cracks and crevices to remove all Simple Green/Crystal Simple Green residues. Unfinished, uncoated or unpainted aluminum cleaned with Simple Green products should receive some sort of protectant after cleaning to prevent oxidation."
..
Instructor
Joined: May 2008
Posts: 150
Likes: 182
From: WA State
I have been using Simple Green Extreme Aircraft Cleaner the last couple years on my dragster. It does not discolor aluminum like original Simple Green and is elecronics safe as well. I mainly use it on the rear suspension 4 link of my dragster which gets gunked up from rubber and nasty water from the burnout box. I mix it 50/50 in a spray bottle, spray it on, let it sit for a couple minute and hose it off. It works unbelievably well.
Melting Slicks
Joined: Feb 2018
Posts: 2,177
Likes: 1,044
From: North Texas