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How To Wash A Semi Truck Engine? (11 Best Tips For Newbies)

Semi-truck engines can quickly pick up a lot of dirt.

Mix that in with the grease and oil on the engine, and you could end up with an incredibly dirty engine bay.

It’s essential to keep the engine clean, not only for it to look better but also for the engine to perform better and last longer.

Read on to find out exactly how you can clean your semi-truck engine.

Here’s a short summary on How to Wash a Semi Truck Engine:

To wash a semi-truck engine, make sure to cover up any electrical parts on the engine. With a relatively warm engine, apply some degreaser to the dirty areas in the engine bay. Allow the degreaser to sit. Rinse the engine with a standard low-pressure garden hose. Let it dry and enjoy a clean engine.

Is it OK to Wash a Semi Truck Engine?

It’s fine to wash your semi-truck’s engine if you do it properly. If you’re using the right equipment and follow the proper steps, cleaning the engine will be easy and effective.

Engines are often greasy and full of oil. However, when dirt gets mixed in with the natural grease found on an engine, it could hamper its performance and overall lifespan.

When the engine becomes hot from running, the grease and oil become less viscous, which allows it to flow more easily.

If there is dirt trapped in with it, the dirt can make its way into the integral parts of your engine, which could cause damage to it.

This makes it essential to keep your semi-truck engine clean. Cleaning the engine bay is often overlooked when semi-trucks are cleaned or maintained.

Why should you Wash your Semi Truck Engine Bay?

Keeping your semi-truck engine bay clean is vital to the performance and the lifespan of the engine. It will also look much better if the engine bay is clean.

When dirt becomes trapped in the engine bay, there is a risk of it making its way into the integral parts of the engine and causing damage.

Dirt can also speed up rust in the engine bay. If the semi-truck engine bay is not cleaned regularly or properly, there may be signs of rust build-up.

What is the Best Way to Clean a Truck Engine?

There are two main ways to clean a semi-truck engine, however, one is recommended over the other.

The first method is steam cleaning. This involves using steam to clean dirt and grease from the engine bay. However, there are two problems with this method of cleaning.

The first is that it is extremely expensive. You need specialized equipment to clean the engine in this way which can cost a lot of money.

The other problem is that you have less control over where the steam goes. This means that it can affect the parts of the engine that you are not meant to wash, such as the ECM, starter, and alternator.

The best way to clean a semi-truck greaser is to use the old-school method. This is done by using a degreaser, a brush, and a standard garden hose.

What Equipment would you Need to Wash a Semi Truck Engine?

To properly clean the engine of a semi-truck, you need some equipment. Luckily there is nothing outrageously expensive or specialized required to clean a semi-truck engine.

The first thing you will need is a degreaser. This is a chemical that will help to remove any dirt and grease from the engine.

Next, you will also need some plastic garbage bags with rubber bands to cover the critical parts that cannot be washed on the semi-truck engine.

You might need to use some brushes; nylon and wire brushes work best. This will help you to scrub the hard-to-reach areas in the engine bay.

You will also need cold water and a standard garden hose to rinse the engine down after cleaning it.

What Cleaning Agents can uou Use to Wash a Semi Truck Engine?

The best cleaning agent to use for your semi-truck engine is an engine degreaser. These can be found in many hardware stores and even fuel stations.

There are two types of degreasers you can choose from. These are solvent-based and water-based.

There aren’t many differences between the two. However, solvent-based degreasers are more effective and work faster than their water-based counterparts.

The downside, however, is that it is a relatively strong solvent, and it can be toxic.

If you are sensitive to solvent-based products, it is recommended to use the water-based degreaser instead.

How to Wash a Semi Truck Engine?

Washing your semi-truck engine is relatively easy; however, there are some crucial steps that you need to follow so that you do not damage the engine.

Here are the steps to washing your semi-truck engine:

  1. The first step is to take one of the brushes and remove most debris and dirt from the engine. You don’t need to focus on grease and oil but more on dust and sand. Try to focus on the grill and the exposed areas of the engine.
  2. The next step is to warm up the engine. Simply leaving the engine to idle for 5-10 minutes will warm it up enough to reduce the viscosity of the grease and oil on the engine.
  3. When the engine is warm, switch it off and cover up the critical parts of the engine. You can easily do this with garbage bags and some rubber bands. You will need to cover the alternator, power steering filler, air intake, ECM, and any electrical parts with wiring.
  4. Now you can apply the degreaser to the engine. Make sure to cover all the dirty areas. Depending on how dirty the engine is, you can let the degreaser sit for between 5 and 10 minutes. You can use the brush to scrub the engine down once again in the hard-to-reach areas to make sure you get all of the dirt and grease off.
  5. After the degreaser has had some time to work its magic, you can rinse the engine down. Make sure not to use any high-pressure equipment. A standard garden hose will do the trick.
  6. The final step is to let the engine dry. The engine tends to dry quickly because it will still be warm. It can typically dry within 20 minutes. You can also use a dry cloth to wipe most of the water away, allowing it to dry much quicker.

Should you Dry the Semi Truck Engine Bay after Washing it?

It is always best to ensure that your semi truck’s engine bay is dry after washing it. The main risk is the integral parts that you covered when washing the engine.

If the engine bay is still wet, there is a risk that it might become damaged from the leftover moisture in the engine bay.

You can let the engine bay dry naturally by leaving it open for a few minutes. However, if you are in a hurry, you can use a dry cloth to dry the engine bay.

Is it Safe to Pressure Wash your Semi Truck Engine?

It is not safe to pressure wash the engine of your semi-truck. The fragile parts of the engine can become damaged if high-pressure water is used against it.

If you use a high-pressure washer on your semi-truck engine, the dirt and grease can also be forced into some components. This could cause even more damage.

It is recommended to use a standard garden hose when washing your semi-truck.

What Parts should you Cover when Washing an Engine?

There are several vital parts you need to cover up when you are washing your semi-truck engine.

These are primarily electronic parts that could become damaged when in contact with water.

These parts include the starter motor, alternator, ECM, air intake, and power steering filler. You also need to avoid any wiring and plugs leading to other electrical components on the semi-truck.

You can cover these parts with garbage bags when washing your semi-truck and tie them down with rubber bands.

Can you Wash a Semi Truck Engine while Hot?

A semi-truck engine should be warm when you wash it but never hot. If the engine has run for between 5-10 minutes from a cold start, it should be warm enough.

If the engine is warm, it allows the degreaser to work properly as the oil and grease on the engine will become warmer and less viscous.

However, if the engine is hot, the degreaser could catch fire as it is a flammable solvent. If you’re unsure whether the engine is too hot, it is best to wait for it to cool down first.

How do I Clean Gunk Out of my Engine Bay?

Dirt can often because clumped together when it mixes with the grease and oil on the engine.

This can leave a lot of gunk trapped on the engine and within the engine bay.

The degreaser will likely make it much easier to remove. However, you may need to use a brush with stiff bristles to scrub the dirt off the engine in some cases.

Rinsing the area with water after scrubbing it will also help to remove any leftover dirt and grease that might be there.

Best Tips when Washing your Semi Truck Engine

Doing some research of your own is always a good idea before you start cleaning your semi-truck engine.

You must find a suitable degreaser and not just use the first one you see.

Cleaning your engine always becomes more manageable and less time-consuming when you do it more regularly.

Create a schedule you can stick with to ensure that your engine is always in top shape.

Get all the equipment you need and keep it in one place so that you never have to rush around to try ad find everything you need when you want to clean the engine on your semi-truck.