Is it safe to wash a car engine?

This blog post will answer the question, ‘Is it safe to wash a car engine?’, and cover topics like tools and other materials required to clean an engine, different ways to clean an engine, and types of engine cleaners.

Is it safe to wash a car engine?

Yes, it is completely safe to wash a car engine provided certain instructions are kept in mind. A small blunder can cause severe damage to the engine and its components.

Components like wires, cables, and other important sensors when exposed to water can suffer severe electrical damage and might also face a short circuit. Therefore, all electrical components need to be covered properly either by a plastic coating or other similar protective layers.

These components when malfunctioning, need to be replaced immediately and might result in costly repairs.

Tools and other materials required to clean an engine

These are the following tools and materials required to clean a car engine:

Tools required

  • Stiff bristled brushes
  • Dripping pans
  • Masks
  • Hose
  • Gloves
  • Safety glasses
  • Screwdrivers
  • Spray bottle
  • Wrench

Materials required

  • Degreaser
  • Tape
  • Absorbent pads
  • Plastic bags

Different ways to clean an engine

The following are the different ways to clean an engine.

Degreaser and pressure washer method

One of the most common methods to clean a car engine. A degreaser is used to clean the entire engine bay. Parts that have persistent waste such as dirt and grime need to be brushed off by a stiff-bristled brush. 

The water needs to be dried as soon as possible or else it might cause rust.

Glass bead and soda blasting method

To get rid of carbon deposits on the aluminum parts of the engine, baking soda or glass beads are used. This method is especially useful for cleaning smaller components of the engine. 

However, it should be noted that if not done correctly, it can leave a residue behind that can cause a premature engine failure.

Hot tank method

This method involves the dirty engine components being dipped in hot water or in a chemical solution that is caustic by nature. This is mainly aimed at cleaning parts that have a serious waste buildup of dirt and grime. This method is, however, ineffective against rust and residue.

Carbon cleaning

Carbon deposits in car parts like valves and exhaust pipes can affect performance drastically. This method involves releasing hydrogen and oxygen into the water via the car’s air intake and exhaust system.

The chemical result that occurs, as a result, helps in getting rid of the carbon deposits.

Steam cleaning

This method is helpful for performing a deep clean in case of the heavy build-up of dirt and grime. No chemicals are needed to clean as steam is hot enough to remove the heaviest and most persistent deposition of waste.

Different types of engine cleaners

These are the various types of engine cleaners available in the market.

Cleaners based on petroleum

These types of cleaners contain ethanol along with other distillates that help in cleaning dirt and grime buildups along with other lubricants.

Cleaners based on metal solvents

These types of cleaners are used to clean joints and other bearings and are particularly helpful in getting rid of persistent grease.

Cleaners based on vapor solvents

These types of cleaners need to be heated to vaporize before cleaning.

Cleaners based on ultrasonic waves

These types of cleaners manipulate ultrasonic waves to clean grease and grime from engines. They are, however, expensive to implement and are not used very often.

Cleaners based on foam

These types of cleaners are ideal for electrical components in an engine and must be wiped off without applying any water.

Cleaners that are environment-friendly

These types of cleaners are made from naturally available ingredients like vinegar, baking soda, lime, soap, etc., and can be used without posing a threat to the environment.

Criteria for selecting the best engine cleaner

These are the following criteria that need to be followed to ensure we select the ideal engine cleaner.

Cleaning formula

The cleaner should not contain any toxic or environmentally hazardous chemicals that can pose a threat to both the driver and the car engine.


An ideal engine cleaner should not contain harmful vapors and should not emit any kind of odor from under the hood that can make driving difficult.

Residue Formation

The cleaner should not leave behind any kind of residue as that is another problem added on top of cleaning an engine.


The engine cleaner should be flexible so that it can be used on different kinds of surfaces instead of a particular metal or alloy part. It should also be usable on rubber and plastic-based components.

Research shows the various steps to be followed while using a WD-40 degreaser to deep clean the engine.


This blog post addressed the question, ‘How do you clean a car engine’.

We came to know about the various tools that are needed to perform a car engine cleaning. Furthermore, different ways of engine cleaning along with different types of engine cleaners available have also been discussed. Please feel free to comment on the content or ask any questions in the comments section below.

Frequently Asked Questions (FAQs): How do you clean a car engine?

Can you hose off your engine?

An engine can be cleaned by using a garden hose or a pressure washer, however, it is important to keep in mind that a pressure washer should be operated at low settings and should be sprayed from a distance.

Will WD-40 damage an engine?

WD-40 is more flammable than engine oil and can cause a huge fire.

What is the best engine cleaner?

Orange degreaser from Chemical Guys Signature Series is one of the best engine cleaners around as it implements a citrus-based formula to remove the buildup of dirt, dust, debris, and grime from the engine bay.