For years it was said that you didn’t need to clean a diesel engine. Over time, as knowledge of proper engine care has increased, we have learned that not cleaning your diesel engine can potentially take time off the life of your vehicle/equipment. It can also lead to repairs and replacement of parts that may have otherwise been avoided.
Some diesel engine models, such as the Ford Powerstroke, will include instruction on how to clean the engine. However, for those without that knowledge, we have written out this guide on how to clean your diesel engine like a pro.

Steps to Clean a Diesel Engine
Many of the steps involved in cleaning a diesel engine are the same as those in a gasoline engine. There are only a few minor differences.
- Remove any debris that may be stuck in the grill or under the hood. You can pull larger leaves and sticks out by hand, but for smaller material, you will want to use a brush to sweep things out.
- For easier cleaning, you will want the engine warm. Run the engine for a good five to 10 minutes so that the oil and grease are nice and loose.
- This step is very important and should not be skipped for any reason. There are around four items under the hood that must be covered for protection. These items include the alternator, air intake, sensors, and power steering filler. You can use plastic baggies to cover the items and secure them in place with an elastic band. If you are unsure where to locate these items, use your owner’s manual as a guide.
- Next, spray a degreaser across the engine and inside of the hood. Spray from the bottom up to avoid having the cleaner drip on you while you are working. Leave the product on for up to five minutes but no less than three.
- Take a brush with a long handle and scrub things down, making sure not to miss the harder to reach places and spots that are especially dirty.
- Now it’s time to rinse. No power wash or high-pressure spray needed. All you need is a gentle flow of water from a hose. Any sort of spray could result in water getting in something you don’t want it to, potentially causing damage.
- The final step is letting the engine dry. You can allow the engine’s heat to dry the water, however, if you wish to avoid spotting you will want to use a cloth and dry some by hand.
Extra Tips
Many people swear by common house-hold degreasers when cleaning their diesel engine. However, we wouldn’t recommend them. Some commonly used products that we suggest you avoid include Fantastic, Simple Green, and Formula 409. Ingredients in these items can damage aluminum, titanium and even high-strength steel. The hydrogen in the cleansers can also damage electrical connections by making materials brittle. Instead, we suggest sticking to a product designed for engine care. Look for something that is citrus-based or water-soluble.
Gem State Diesel – We’re Here for You
Gem State Diesel in Meridian, ID was established in 2010, and we have a reputation for superior diesel repair and service standards. We provide bumper-to-bumper service of Ford, GMC, and Dodge diesel pickups with fast turnaround time. For any of your diesel service or repair needs, just book an appointment online or give us a call at (208) 288-5555.