The diesel engine in your semi truck has to work hard when you are transporting heavy loads. This can really take a toll on your engine over the course of time, sometimes leading to diesel engine failure. In order to keep your truck running and on the road, you should keep your eye out for the signs of diesel engine failure. Knowing these signs ahead of time can help you avoid a catastrophic breakdown during a big transportation job.

1. Your Diesel Engine is Consuming a Lot of Oil

Are you finding yourself having to top off the oil in your truck more frequently? If so, this likely means your diesel engine has an oil leak somewhere. This is a big problem because low oil levels can lead to engine corrosion, which in turn can lead to diesel engine failure. If your engine breaks down while you are on the road, the results could be devastating. The best-case scenario would be that you have to call a tow truck and you lose valuable driving time. The worst-case scenario could be your semi truck breaking down in the middle of the road and causing an accident. To avoid diesel engine failure, you should check your piston rings and cylinder liner to see if they are the cause of the oil leak. Get the offending component repaired or replaced as soon as possible.

2. Your Semi Truck is Experiencing Poor Fuel Economy

As a diesel truck driver, you know how often you usually have to fill up your fuel tank and about how much you usually spend on diesel fuel. You also are familiar with how far you can drive on a full tank. If you are having to stop to fill up on diesel more often and you are spending a lot more money on fuel, then your semi truck may be on the brink of diesel engine failure. Low fuel economy can be the result of damaged or worn out fuel injectors or rings. Malfunctioning fuel injectors can cause extra diesel to leak into the chamber, which can lead to a number of engine problems. If allowed to progress, these problems can result in complete diesel engine failure. You should get those worn out and damaged fuel injectors and rings repaired quickly so that you can avoid a major breakdown.

3. You Hear Strange Sounds Coming from Your Diesel Engine

You know what your diesel engine is supposed to sound like when it’s running. That beautiful roar of your engine coming to life followed by a consistent hum—it’s unmistakable. If new sounds enter the mix, they could be an indication that your diesel engine is experiencing major problems. Engine knocking can be a sign of oil contamination or combustion timing issues. It is also frequently the result of damaged liner seals, a worn piston skirt, or main bearing problems. If your diesel engine is making a clunking noise, the main or rod bearing may be worn down. A pinging sound can indicate leaking injectors, and a tapping sound can be a sign that the engine’s valve clearances have lost their proper clearance. The problems that cause your diesel engine to make these noises can be serious and lead to total engine failure if not repaired by a diesel mechanic.

4. You Notice Poor Engine Braking

If your diesel engine is failing, your semi truck may have a difficult time both speeding up and slowing down. When you notice that your engine brake is not slowing your diesel truck as quickly as it is supposed to, then your diesel engine is likely having problems and needs to be repaired by a diesel mechanic. If you do not get the problem resolved quickly, you risk complete diesel engine failure and the safety of other drivers on the road.

5. Your Truck Has Lost Power

A loss of engine power is an easy to notice sign of impending diesel engine failure. How well does your semi truck pull heavy loads? How long does it take to get up to speed? Failing diesel engines do not have as much power to pull heavy loads or to reach top speeds. The cause of this issue is most likely a loss of cylinder compression, which occurs when piston rings, valves, head gaskets, and related components become worn out. If your diesel truck continues to have these problems and to lose power, the diesel engine will eventually completely fail. To avoid diesel engine failure, get your engine checked out by a diesel mechanic as soon as you start to notice a loss of power.

6. Your Diesel Engine is Having Trouble Starting

When your diesel truck just keeps cranking and isn’t starting up, this can be a sign of a number of different issues, including low compression. Proper compression and combustion are necessary for a diesel engine to start and run; the engine needs to have the right pressure to cause the combustion. Without this pressure, the diesel engine won’t start correctly. When the components in the combustion chamber wear down, the engine cannot achieve the necessary compression. These components include the piston, rings, valves, cylinder liners, etc. The starting problems will be much worse in cold and hot weather when this is the cause. Because this is just one of the possible reasons your diesel engine isn’t starting, you should have a diesel mechanic take a look as soon as possible to see what the problem is so that your truck does not experience complete diesel engine failure.

7. Your Diesel Engine is Producing Blue Smoke

Blue smoke is never good. It means your diesel engine is burning its own oil. This can occur because of an oil leak, an overly full oil chamber, or a worn cylinder. If your semi truck is regularly producing blue smoke, this is a sign of a major problem for your diesel engine. If allowed to persist, this issue will lead to more severe problems and will eventually cause total engine failure. Ask a diesel mechanic to check out the problem to repair any leaks or cylinder issues before they become worse.

8. Your Diesel Engine Won’t Stop Running After Turning It Off

The key has been turned off and everything else is off, but the engine is still running. A diesel engine that won’t stop running can be an even bigger problem than an engine that won’t start. This rare condition is known as diesel engine runaway and can occur when your diesel engine is worn down. Even though you’ve turned off the engine’s access to fuel, it can find an alternative fuel source in oil. Worn down pistons, rings, etc. can let an oil mist into the combustion chamber, allowing the engine to keep running by burning this mist until it runs out. If your turbocharger fails, it can allow oil into the combustion chamber as well, giving the diesel engine plenty of fuel to run until it eventually explodes. You need be very careful if your diesel engine doesn’t shut off after turning a couple of rounds, as a diesel engine runaway is very dangerous.

Diesel Engine Repair and Maintenance from an ASE Certified Diesel Mechanic

If you think your diesel engine is starting to fail, then you need take your truck to a diesel mechanic. A diesel mechanic will know where to look to find the problem and can fix it before it turns into a more serious issue. Here at Certified Diesel Solutions, our team of ASE certified diesel mechanics has years of experience as well as access to all the latest tools and diagnostics equipment. We can find the root of any diesel engine issue and solve it, giving you peace of mind that your truck will safely get you and its heavy load to your destination. Bring in your diesel truck for preventative maintenance and repair services. To schedule service, reach out to us today at 865-964-6598 or online.