How to clean a car engine: inside and out

clean a car engine

A car engine can be a visual marvel, a work of engineering. However, when you lift the hood of the car and see a dirty engine, it gives quite a bad impression, and even looks like a much older engine than it really is. Therefore, in this guide we are going to explain to you step by step how you can clean the engine, not only on the outside, but also how to do it on the inside.

In fact, do this It not only has aesthetic repercussions, it can also be a good option to achieve other advantages, as I will explain later…

Reasons: is it important to clean the engine? How often?

Here we go to Differentiate between interior and exterior cleaning the motor:

  • outside cleaning: Cleaning the outside of the engine is mainly an aesthetic issue, since the engine, with grease or oil, tends to accumulate a large amount of dust and dirt. But it is also important to protect the parts most susceptible to corrosion, since the accumulation of dirt and moisture can end up damaging some metal components, so cleaning could extend their life. Another reason to clean the engine is to improve cooling, since dirt can clog the radiator grilles, or generate layers on the metal parts that prevent heat dissipation adequately. On the other hand, a clean engine makes it much easier to detect leaks. It is not necessary to clean the engine very frequently, but doing so once a year would not be bad. However, this will depend on the use, since if you go on dusty roads or for off-road driving, they will get dirtier.
  • Interior cleaning: in the case of internal engine cleaning, it can be more or less thorough. Cleaning the engine internally can serve to improve performance, eliminating certain oil and dirt deposits inside the engine. It can also eliminate abrasive residues that can increase the wear of the parts that rub, such as pistons, etc. That will lead to longer engine life. Another objective of cleaning may be to reduce emissions, so it is something you should do before going to the MOT to pass it without problems if you have an old car. Of course, it could even reduce vibrations and engine noise. In these cases, cleaning does not need to be as periodic as the exterior, there is no exact frequency, but in the case of older cars, cleaning before each technical inspection would be good.

Engine cleaning, both internal and external, can be done in several ways, as I will describe later. Some using specific products, and others with more rudimentary methods. AND It is not necessary to disassemble the engine or have any mechanical knowledge. in all cases.

Remember that if you don't know what you are doing, it is better to leave the cleaning in the hands of a professional.

Clean the engine externally

clean the engine, external

Keeping your car engine clean is not only a matter of aesthetics, but it also has important benefits for its operation and useful life, as I mentioned previously. Next, we can see two different methods, one faster, and another deeper:

advance precautions

Before starting to clean, be sure to:

  • Disconnect the car battery before starting.
  • Let the engine cool completely before cleaning.
  • Cover the battery, alternator and other electrical components with plastic bags to protect them from water and the rest of the products used.
  • Work in a well-ventilated area.
  • Be careful when handling chemicals, such as solvent-based engine cleaner. Use protective gloves, glasses, etc.
  • You can clean the electrical elements dry.
  • Do not spray water directly on the engine elements.

Quick method (10 minutes)

In order to perform a quick and easy engine cleaning, you will need the following tools and products:

  • Brush, brush.
  • Handheld vacuum cleaner or pressure washer
  • rags
  • Bucket with water
  • Degreaser
  • Multi-use cleaner
  • Plastic polish (optional)

As for the the steps to follow, They are:

  1. Remove dust: Use the brush, brush or vacuum cleaner to remove dust from the engine and inside the hood. For parts that are not part of the engine, such as the sides of the hood, the body, etc., you can use a pressure washer.
  2. Clean the visible parts: Dampen a rag with all-purpose cleaner and clean the plastic covers, hoses, fluid reservoirs and body parts.
  3. Eliminate fat: If there are grease stains, apply degreaser with a cloth, avoiding contact with rubber sleeves and plastic elements, as it can be corrosive to these non-metallic elements.
  4. Dry and polish: Let it air dry and apply plastic polish for a better finish (optional).

Method for deep cleaning (20 minutes)

Another method that is somewhat slower than the previous one, but that allows a more thorough cleaning, when the dirt is greater or it is an older engine, you will need the following tools or products:

  • Brush, brush.
  • Handheld vacuum cleaner.
  • Steamer or similar pressure steam cleaner
  • rags
  • Scourer
  • Bucket with water
  • Degreaser
  • Multi-use cleaner
  • Plastic polish
  • Distilled water
  • metal cleaner

Once you have these accessories, and following the same previous recommendations of the slow method (protect the electrical components, and be careful with the degreaser and areas with grease, do not remove it), you can proceed to follow these steps To clean the engine:

  1. Remove dust- Remove dust from the engine and hood as in the previous method.
  2. Clean visible parts: Apply all-purpose cleaner to a rag and clean the engine parts. You can use a handheld vacuum or pressure washer for hood and structural parts, but not directly by blasting water at the engine.
  3. Eliminate fat: that degreaser carefully for oil stains.
  4. steam wash: Clean the engine with the steam cleaner and distilled water. Remove the plastic protectors, except for the one on the air inlet. Air dry.
  5. remove rust- Apply a 3-in-1 product or WD-40 with a scouring pad to remove rust from screws, nuts and other metal components.
  6. Dry and polish: Let it air dry and apply plastic polish to improve the appearance of the details.

Clean the engine inside

clean internal engine

For a more thorough cleaning of the engine, you need to have some mechanical knowledge, and in that case, I believe that no steps are needed, since you will know perfectly well how to disassemble all the engine components and how each one can be cleaned correctly. . However, this is a rather tedious task, which also implies having the necessary tools, etc. However, you can also do it without having to dismantle the engine, using products that exist on the market, such as crankcase cleaners.

For diesel cars, especially the older ones, to pass the ITV without problems due to emissions, you also have some cleaning additives on the market like:

Once added, you just have to take the car on the highway to give it some “reed” and get all that carbon and residue out.

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