Dirty Engine? 9 Steps to Cleaning Engine Sludge with Diesel!

Engine oil molecules break down over time as a result of oxidation. They also mix up with dirt, metal shavings, water, etc., to build up sludge inside the crankcase. If the sludge isn’t cleaned properly, the engine performance and durability drop noticeably.

So, is cleaning engine sludge with diesel safe? Yes, you can clean engine sludge with diesel. Besides dedicated engine flush products, diesel is an excellent solvent. It cleans the gunk inside the crankcase to keep the engine operating smoothly.

Let me give you a detailed explanation of how to use diesel to clean engine sludge safely.

Cleaning Engine Sludge With Diesel: How Does It Work?

When the engine oil gets clumpy and sticky, it is known as the engine sludge. The sludge sticks to the inside of the crankcase. Sometimes, the sludge can block the oil channels and prevent the engine oil from spreading around.

As a result, the engine can heat up excessively. Sometimes, the engine temp spikes then returns to normal and the problem continues intermittently. When you put diesel into the crankcase, it dissolves the sludge built inside the crankcase.

The dissolved sludge then comes out through the drain plug, leaving a clean engine for the next oil refill.

Is Cleaning Engine Sludge With Diesel Safe?

The question arises because diesel is a combustible fluid. If it is used near an open flame, diesel can wreak havoc. Due to its combustible nature, diesel is considered risky. So, how can it be safe to clean engine sludge with diesel?

This is because diesel isn’t used near any flame source while cleaning the engine. Diesel has very good solvent properties and it is normally poured into the engine oil reservoir. The engine is only started after closing the oil reservoir cap.

The diesel then moves through the oil channels and cleans the sludge. It doesn’t come in contact with any source that can ignite the diesel. So, cleaning engines using diesel is generally safe. Still, you need to be cautious while working with diesel.

How to Clean Engine Sludge With Diesel: A Step-by-Step Guide

Before you start cleaning the engine, gather the following tools to make your task easier.

• Large oil pan
• Socket wrench
• Oil filter wrench
• Oil filter
• Funnel
• A few quarts of diesel

Step 1: Lift the Car

If you are working in a normal garage, you can simply lift the car using hydraulic jacks. It would be better if you could arrange floor jacks. Make sure the car is horizontally aligned.

Step 2: Heat Up the Oil

Turn the engine on and let the engine run for some time. It will heat up the oil a bit and increase its flow rate. Running the engine for about 5 minutes is good enough. If the oil gets too hot, draining it can be risky.

Step 3: Place the Oil Pan

Locate the drain plug in your car. In some cars, you need to remove the underbody protection or engine splash shield to access the drain plug. Place a large oil pan right below it.

Step 4: Remove the Drain Plug

Use a socket wrench to remove the drain plug. Do it slowly and wear hand gloves to keep yourself from the mess. Let all the old engine oil drain. It might take about 15-20 minutes, depending on the engine oil capacity of your car. When no more oil is dripping, close the drain plug.

Step 5: Pour Diesel and Engine Oil into the Reservoir

Put a funnel onto the engine oil reservoir. Pour a combination of diesel and engine oil into the reservoir. The ratio of diesel and engine oil should be 80:20. Alternatively, you can use CRC Engine Flush to clean the sludge.

Step 6: Run the Engine

After pouring the diesel, turn the engine on. The engine should idle so that the tear on components is minimal. After running the engine for about 10 minutes, turn it off.

Step 7: Drain the Diesel

Place the oil pan below the drain plug again. Then, remove the drain plug and let the diesel out. Finally, close the drain plug and tighten it with the socket wrench.

Step 8: Replace the Oil Filter

Besides draining the oil oil, you should also replace the used oil filter. Remove the used oil filter by twisting it with an oil wrench. Place the new filter into the housing and tighten it properly. Then, close the engine splash shield. You might ask, is an engine splash shield necessary? Well, it will protect the underbody from dirt, mud, water, etc.

Step 9: Refill Engine Oil

Take the engine oil reservoir cap off. Pour the right amount of engine oil into the reservoir according to the car’s manual. Also, use the right grade of engine oil. After filling the oil, run the engine a bit and check the dipstick to find the oil level. The engine oil should be at the High or Max mark on the dipstick.

Is Cleaning Engine Sludge With Diesel Better Than Engine Flush?

Not necessarily. Engine flushing oils have various additives that are more effective in cleaning the sludge. But you might not always have engine flushes handy. In such cases, diesel can be a good alternative to the engine flush.

Some oil additives go directly into the reservoir with the oil to keep the engine oil cleaner. You can use these additives to get rid of nasty engine sludges. Regular cleaning also reduces the hassle of removing stubborn sludge.

People Also Ask

Car owners often ask the following questions regarding the use of diesel to clean engine sludge. Check the answers out.

Conclusion

Sludge buildup inside the engine lowers the thermal performance of the engine oil, hence affecting the engine’s performance and lifespan. It is crucial to clean the engine sludge. As an alternative to traditional engine flushes, diesel is also used to clean the gunk.

When you use diesel to clean engine sludge, you need to remain careful not to ignite the fuel. Follow the step-by-step guide above to get the job done with the least hassle. Build a habit of changing the engine oil in time to prevent further damage to the engine.