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How To Wash a Semi Truck Engine?

How To Wash a Semi Truck Engine?

Many people think it is challenging to clean a semi-truck engine. However, it is easy, and you can do this by following these steps with some precautions.

How To Wash a Semi Truck Engine? You can wash a semi-truck engine by using a degreaser, steam, and household soap or detergent. These agents can easily remove the accumulated dirt, rust stains, oil leftovers, and loose grease from the inner surface. Park the truck, open its hood, remove the debris, apply the cleaning agent, clean it carefully, and dry it in the open air. It is not recommended to have a pressure spray for washing the engine. You have to clean it twice a year for efficient power transmission, which helps to reduce fuel consumption.

The trucks on the road have to face the dirt and debris accumulating in the engine leading to faulty power transmission.


The degreaser is an agent specially designed to remove the toughest stains from the engine parts.

It can give them a shiny and dust-free surface that can function at its full potential and works with sufficient efficiency.

It is better to select a suitable product for the targeted surface, and it should have a wide range of versatility.

Some are perfect for rubber and plastic surfaces, and others are helpful on flat metal surfaces of the semi truck.

It is a gentle and safest material for vehicles, but you have to use it in a sufficient amount by following the instructions.

You should have a brush, a garden hose, and enough chemicals for the manual washing process.

Environment-friendly degreaser

Many people think that these products dont harm the environment, but this is not true.

Many of these washing degreasers are consist of household natural materials like some lemons and vinegar with a pinch of baking soda.

These are easy and convenient without posing any hazardous damage to the sensitive machine of the truck.

Use non-toxic products are for this purpose, and they work well.

Liquid-based degreasers

Liquid-based products are usually powerful but have an abrasive effect.

It is better to prepare their dilution for efficient functioning and avoid the burning patches on the semi truck engine.

These are perfect for heavy-duty machines, but you can get rid of the built-up grime with full attention paid to the dilution process.

Ammonia and foam-based agents

Ammonia-based degreasers are not efficient like others but have a particular behavior against the oil and grease over the sensitive components due to their mild nature.

Foam-based agents require no rinsing with water, and therefore they are not time-consuming, but these are limited in their working.

Both products can help you with repeated cleanings at regular intervals, but they are not suitable for removing the adherent stains.

Petroleum-based degreasers

These are oil degreasers, but they are not versatile, and you cannot use them on all surfaces of the interior parts in an engine.

The grease, oil, and lubricants have some leftover on the outer surface, and these are easy to wash with petroleum products.

Do not allow the children to come in the vicinity where you want to wash the vehicle because petroleum products can have some dangerous effects.

Cleaning by steam

Some people use steam to remove the dirt and grease from the semi truck engine because they are usually not well aware of the degreasers.

It has more limitations than benefits, and for that reason, the professionals suggest not using it again and again.

It is expensive to operate this process as it requires a special kind of equipment that is not available all time, consuming more money to order it.

There is no restriction on steam to go only to the targeted places, as it is free to move, and it can easily damage the inner components like the alternator and starter motor.

Soap and detergent

Some truck owners find it better to use household soaps and detergents for their semi-truck engine because it is necessary to clean it regularly.

There is quick access to them, and you do not need to spend extra money to buy some chemically constituted degreasing agents.

The kitchen and fabric detergent typically have some chemical agents in their composition, designed to remove the casual dirt and oil but use them in dilutions with water.

These chemicals are helpful to achieve your target, permitting you to enjoy a long journey without jerks on the way to your destination.

You have to keep in mind that not every household product is suitable for your vehicle’s bay, and first check the content list in this detergent.

It is better to use dishwashing soap because it has a less corrosive nature but does not allow the soapy water to reach the inner parts.

Steps to wash a semi-truck engine

Park semi-truck in the garage, turn off its engine and allow it to cool for an effective washing process.

Before starting the work, pick up the degreaser, soap, water, a garden hose, brush a fine cloth, duster, plastic bags, and a stirrer for making the dilution.

You have to bring all this material to the garage or to a place where you can wash the truck and do not allow the children to visit this place.

This step is a prerequisite because sometimes it is problematic to stand and search for the desired tool.

Remove the debris

Semi truck has to bear the high-pressure winds, harsh scorching rays of the sun, and steady rains while having a journey on long roads.

This exposure results in the accumulation of dirt, debris, and rust all around its interior components.

It is compulsory to remove this dirt with a duster or a fine cloth but make sure that it should not react with the lubricating fluid over the parts.

A brush is perfect for removing the minute dirt particles from the hood, grill, wires, and connectors by just a mear swipe.

Warm up the engine

Warming of the engine is necessary to have the clear and loose appearance of the leftover dirt and grease.

You have to idle the engine for a particular time, and usually, the recommended one is about 10 to 15 minutes.

It is not suitable to idle for a long time as it is a general thought that more warming will lead to more loose grease, but the situation is not like that as some wonders.

The truck needs cooling for a few minutes after this continuous idling.

Covering the inner parts

It is mandatory to cover the inner assembly of sensitive parts before applying anything to wash the engine.

There are some components in the semi truck engine like air intake, sensors, power steering filler, and the alternator under the hood.

You can cover these parts using plastic sheets or paper covers but do not allow them to go in their small crevices.

Plastic baggies covering bounded with rubber bands are perfect in this case.

Apply the cleaning agent

Next apply the cleaning material like degreaser and soapy solution.

You can apply it from any side of the engine but if you want to start from the bottom, make sure that no drops should fall on you.

A minor act of ignorance for falling the drops on yourself does not harm you but pay extra attention for the degreaser.

Allow the material to stay for a few minutes depending upon the nature of the surface, but 4-6 minutes are perfect for any material.

Use a scrubber to ensure a complete clean-up from the minute details and hidden parts of the bay, and always make a dilution with the degreaser.

Rinse the surface

Remove all the applied material from the surface and from the minute parts that are difficult to access.

Rinse it all with a garden hose and make sure there are no leftovers but do not use pressure sprays.

You have to be quick and furious during this step because the abrasive hydrogen can deteriorate the steel, aluminum, and electrical wires in the semi truck.

Appropriate drying

The drying is the final step in the whole process, and it is easy to perform.

Many people prefer to dry it in the sun, but you can leave the assembly in an indoor environment for a few hours in the winter season.

There should be no moisture inside because it can damage the quality of the engine when you warm it for running.

The remaining moisture can burn the connectors and wires and leads to rust over the metallic surfaces.

You can apply a lubricating fluid and vinyl protectant to have a shiny surface and remove the protective coverings as the engine is ready to move.

Is it ok to pressure wash truck engine?

The fragile and sensitive parts of the semi truck engine demand light pressure spray for rinsing and washing.

There is a risk in high-pressure cleaning because it can force dirt to move into the small crevices around the connectors and between closely fitted parts.

Since a person’s hand cannot easily reach these crevices, cleaning them with a brush is nearly impossible.

It is perfect to use a garden hose for rinsing, but you can use a 5/7 inch hose for standard pressure washings.

How often to wash a semi truck engine?

For the semi truck running on the long muddy roads, the professionals recommend washing the engine after every 3 months a year.

It is suitable to wash after every 6 months in a year for the vehicle used to have a journey on the carpeted roads with a minimum of dust.

It is better to wash the semi truck once a month to reduce the accumulation of layers of dirt and debris.

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