5 Common Engine Problems in Construction Equipment

This article breaks down five common engine problems seen in construction equipment and explains what causes them, how to spot the symptoms early, and what preventative actions can help avoid costly repairs.

Engine Overheating

One of the most frequently encountered issues in construction machinery is engine overheating. When heavy equipment runs in rugged environments—often under full load in dusty or hot conditions—the cooling system must work overtime. If any part of that system falters, temperatures can spike rapidly.

Common causes:

• Low coolant levels or old coolant that’s lost effectiveness
• A failing radiator fan or fan clutch
• Clogged radiator or intercooler fins due to dirt and debris
• Defective thermostat or water pump

Symptoms to watch for:

• Warning lights on the dash
• Steam or smoke near the hood
• Temperature gauge running into the red
• Reduced engine performance or shutdowns under load

Preventative maintenance is key: flushing the cooling system, inspecting belts and hoses, and ensuring the radiator is free of obstructions can keep the system in check.

Fuel System Contamination

Fuel contamination is a silent killer of diesel engines in construction equipment. It doesn't take much—just a little water, debris, or microbial growth in the fuel tank—and suddenly you’re facing injector damage, poor combustion, and engine stalling.

Typical contaminants:

• Water from condensation or improper fuel storage
• Dirt and rust from deteriorating tanks or fuel lines
• Bacteria or algae in stored fuel (especially biodiesel blends)

Symptoms of contamination:

• Hard starting or extended cranking
• Engine misfires or knocking
• Excessive smoke from the exhaust
• Frequent clogging of fuel filters

Regular fuel sampling, using high-quality filtration systems, and draining water separators daily—especially in humid climates—can drastically reduce the risk of contaminated fuel.

Loss of Compression

Internal engine wear over time can cause a loss of compression, leading to starting issues, poor fuel economy, and a noticeable drop in power. For diesel engines, proper compression is essential to initiate combustion—there are no spark plugs to fall back on.

Causes of compression loss:

• Worn piston rings or cylinder walls
• Damaged valves or valve seats
• Cracked cylinder head or blown head gasket

Signs of compression problems:

• Excessive white or blue smoke
• Low power, especially under load
• Uneven engine performance
• Oil consumption and contamination

A compression test or cylinder leak-down test can help isolate the problem. Depending on the root cause, repairs may range from a top-end rebuild to full engine overhaul.

Turbocharger Failure

Modern construction equipment relies on turbocharged diesel engines to deliver the torque needed for heavy lifting and digging. However, turbochargers spin at incredibly high speeds—often 100,000+ RPM—making them vulnerable to damage if starved of oil or exposed to contaminants.

What leads to turbo failure:

• Lack of lubrication due to oil starvation or blockage
• Debris entering through a damaged air filter
• Excessive exhaust heat causing thermal damage

Warning signs:

• High-pitched whining or screeching noise
• Excessive black or blue smoke
• Loss of boost and reduced engine power
• Oil leaks around the turbo housing

Proper oil changes and clean air filtration go a long way in preserving turbo health. If an engine is shut down immediately after heavy use, the oil can cook inside the turbo—a process called “coking”—so allow a cool-down period to prevent that.

Exhaust System Blockages (DPF or EGR Failures)

Emissions systems are another common trouble spot in modern diesel engines. Diesel Particulate Filters (DPF) and Exhaust Gas Recirculation (EGR) systems reduce harmful pollutants—but when they clog or malfunction, they choke the engine.

Leading causes:

• Skipping regeneration cycles in DPF-equipped machines
• Build-up of carbon deposits in EGR valves
• Faulty sensors misreading flow or temperature

Symptoms of trouble:

• Poor throttle response or limp mode
• Excessive fuel consumption
• Frequent need for manual DPF regenerations
• Check engine light or emissions warning

Routine regeneration cycles and cleaning EGR systems are critical. Using low-quality fuel or letting the machine idle too much can drastically shorten the lifespan of these components.

Stay Ahead of Engine Failure

From overheating radiators to turbocharger failures, engine problems in construction equipment can derail a job site fast. Most of these issues stem from poor maintenance or environmental factors—things that can be monitored and managed with a disciplined maintenance schedule.

Keeping a close eye on fluid levels, fuel quality, air filtration, and cooling performance isn’t just best practice—it’s a safeguard for your bottom line. Proactive inspections and adherence to manufacturer service intervals can prevent these common failures and keep your machines productive.

Need help diagnosing engine problems or planning your maintenance schedule? Reach out to All-In-One Service & Repair in Grantsville, UT, today.