When buying an excavator, the initial cost is only part of the total cost of ownership. The asking price for a used excavator does not include potential hidden costs from future repairs. Problems like fluid leaks can signal expensive failures ahead.
You must inspect used heavy equipment systematically to uncover these issues. A thorough check reveals the true condition of a used excavator. This guide provides a clear checklist to help you assess any used excavator before you commit.
Initial Walk-Around: Gauging Overall Condition and Wear
Your inspection begins the moment you see the machine. A careful walk-around gives you a first impression of its overall condition and usage history. This initial look can quickly reveal signs of either diligent care or serious neglect.
Check the Hour Meter and Machine Age
You should first locate the hour meter. The number of working hours tells you a lot about the machine's life. A typical excavator has a lifespan of 10,000 to 15,000 working hours.
Equipment Type | Average Lifespan (in Hours) |
|---|---|
Excavators | 10,000 – 15,000 hours |
However, the number of working hours does not tell the whole story. A machine with higher hours but a solid maintenance record can be a better investment than a low-hour excavator that was poorly maintained. The age and usage history together help you understand the machine's value.
Inspect for Dents, Rust, and Cosmetic Damage
Next, you will examine the machine’s body. Look past minor scratches and small dents. You are hunting for clues to deeper problems. Pay close attention to critical areas.
Warning Signs to Look For:
Deep Rust: Significant corrosion, especially on structural parts of the excavator, can weaken its frame.
Cracks: Check for cracks around welds on the boom and arm, as these are high-stress points.
Poor Repairs: Look for sloppy weld jobs, which indicate a past failure was not fixed correctly.
Assess the Cab and Controls
The cab is the operator's command center, so everything must work correctly. Climb inside the used excavator and test all functions. A safe and functional cab is non-negotiable for any used machine. Make sure you check the following:
The function of the horn and reversing alarms.
All indicator lights and warning systems on the dashboard.
A well-kept cab often suggests that the previous owner cared for the entire used machine.
The Undercarriage: A Major Source of Hidden Costs
The undercarriage is one of the most expensive parts of an excavator to repair. It can represent up to 50% of a machine's total maintenance budget over its lifetime. A worn-out undercarriage is a major source of hidden costs, so you must inspect it carefully. A thorough check here can save you thousands of dollars.
Examine Tracks, Rollers, and Sprockets
You should begin by inspecting the individual components. Look closely at the tracks, rollers, and sprockets for signs of wear. The metal teeth on the sprockets should be relatively sharp and symmetrical. Worn sprockets will have a hooked or pointed appearance. You can measure the height of the track grousers (the raised bars on the track pads) with a ruler or caliper. Compare your measurements to the manufacturer's wear limits to determine the remaining life.
Pro Tip: For an accurate measurement, clean the dirt off two grousers and the track pad between them. Place a straight edge across the top of the grousers and measure the distance down to the pad. This shows you exactly how much the grousers have worn down.
Look for Uneven or Excessive Wear
Next, you need to look for wear patterns. Uneven wear on a used excavator often points to a misaligned track frame or worn internal components. Walk along each track and check for these warning signs:
Dark oil stains around the ends of rollers, which signal leaking seals.
Sprocket teeth that are worn more on one side than the other.
Visible cracks on the track links or pads.
These issues suggest the used machine was operated harshly or that maintenance was neglected.
Check Track Tension
Proper track tension is critical for the longevity of the undercarriage. A track that is too tight causes rapid wear on components, while a loose track can slip off and cause damage. To check the tension on a used excavator, you must lift one side of the machine off the ground.
The correct procedure involves measuring the sag in the track between the carrier roller and the idler. You can find the specific measurement for the excavator model in the operator's manual. If the tension is wrong, it can be adjusted, but incorrect tension over a long period may have already caused significant hidden costs in wear and tear.
The Hydraulic System: The Heart of the Used Excavator
The hydraulic system is the muscle of any excavator. It powers the boom, arm, and bucket. Problems here can stop a job instantly and lead to very expensive repairs. You must carefully check this system to understand the machine's true health.
Hunt for Hydraulic Fluid Leaks
Your first task is to hunt for hydraulic fluid leaks. A clean machine makes this easier. You should inspect all cylinders, hoses, and fittings for any sign of oil. Pay special attention to common problem areas on a used machine.
At the joints where parts connect
Around valve seats
On the oil pipes themselves
Even a small, damp spot can signal a failing seal that will soon become a major leak. These leaks are clear warnings of future costs.
Test Hydraulic Speed and Strength
Next, you need to test the system's performance. Start the used excavator and let it warm up. You should then operate all the hydraulic functions. Raise and lower the boom, extend and retract the arm, and curl the bucket. The movements should be smooth and responsive.
Slow, jerky, or weak movements are major red flags. These issues can point to several problems, including low hydraulic pressure, worn-out pumps, or air trapped in the system. A healthy used excavator will feel powerful and precise.
Listen for Hissing or Knocking Sounds
Finally, you must listen to the hydraulic pump while the excavator is running. Strange noises often point to hidden damage. A constant hissing sound can mean a relief valve is stuck open, bleeding off pressure. A knocking or sputtering sound often indicates air in the fluid or debris inside the system. These sounds are not normal for a well-maintained used machine. Ignoring them can lead to catastrophic pump failure.
Check the Hydraulic Fluid Condition
The condition of the hydraulic fluid offers a direct look into the system's health. You should always check the fluid before making a decision. First, locate the hydraulic tank's dipstick or sight glass. Pull the dipstick and wipe it clean, then re-insert it to get an accurate reading of the fluid level and condition. The fluid should be clear and have an amber or light honey color.
Pay close attention to the fluid's appearance and smell. A burnt odor is a sign of overheating, which can damage seals and pumps. The color of the fluid also tells a critical story about the excavator.
What the Fluid Color Tells You:
Milky or Cloudy: This indicates water has contaminated the system. Water reduces lubrication and can cause rust inside expensive components.
Dark Brown or Black: This signals the fluid is old and has broken down from heat and pressure. It is no longer protecting the system effectively.
Visible Particles: Dark fluid can also hide dirt, dust, or tiny metal shavings. These particles act like sandpaper, causing abrasive damage to pumps, valves, and cylinders.
Dirty or contaminated fluid is a major red flag. It suggests the previous owner neglected basic maintenance. This neglect on a used machine almost always leads to premature wear and expensive failures. Changing the fluid is simple, but the damage it may have already caused is a significant hidden cost.
The Engine: Powerhouse or Money Pit?
The engine is the heart of any used excavator. A strong engine provides reliable power, while a failing one can become a constant source of expensive downtime. You must carefully evaluate the engine's condition to avoid a costly mistake.
Perform a Cold Start Test
You should always ask to start the excavator's engine from cold. A "cold start" means the engine has not been run for several hours. This test reveals problems that a warm engine can hide. A diesel engine needs to turn over at about 180 RPM to start, which requires a healthy battery. Cold temperatures make this test even more revealing.
Common Cold Start Problems:
Thickened Oil: Cold oil is thick and makes it harder for the engine to turn over.
Weak Battery: Batteries lose significant power in the cold, which can prevent a start.
Fuel Issues: Diesel fuel can gel in cold weather, and frozen water in the fuel filter can block flow.
If the used machine struggles to start, it could signal issues with the battery, starter, or fuel system.
Check for Abnormal Engine Noises
Once the engine is running, you need to listen carefully for unusual sounds. Different noises point to specific problems inside the engine. A high-pitched squeal is often less serious than a deep knock.
Squealing Sounds: A squeal usually comes from a loose or worn fan belt slipping on its pulleys.
Knocking Sounds: A deep knocking or tapping sound is a major red flag. This often means there is excessive wear on internal components like piston rings, bearings, or valves. These are signs of a worn-out engine that may need a rebuild.
Inspect the Exhaust for Smoke
The color of the exhaust smoke from the excavator tells a story about the engine's internal health. A small puff of white or blue smoke on a cold start that disappears quickly can be normal. However, continuous smoke from a warm engine signals trouble. The color of the smoke from a used machine can help you diagnose potential issues.
What It Means | |
|---|---|
White Smoke | Indicates water or coolant is getting into the combustion chamber. This could be from a bad head gasket. |
Blue Smoke | Signals the engine is burning oil. This is often caused by worn piston rings or valve seals. |
Black Smoke | Means the engine is getting too much fuel or not enough air. This can be due to a clogged air filter or faulty fuel injectors. |
Look for Engine Oil and Coolant Leaks
You must inspect the engine for fluid leaks. Leaks are clear signs of poor maintenance and can lead to major engine failure. Your inspection should cover both external and internal leaks. First, look for external leaks. Check around the engine block, paying close attention to gaskets, hoses, and the radiator. You can spot fresh oil as a wet, dark patch. Coolant leaks often leave behind a crusty, colorful residue (usually green or pink). Even a small drip can signal a bigger problem, like a cracked hose or a failing water pump.
Internal leaks are more serious and harder to spot. They happen when fluids mix inside the engine, which can cause severe damage. You need to check the fluids themselves for signs of contamination.
A major warning sign is finding a thick, milky substance in the coolant reservoir or on the engine oil dipstick. This sludge looks like chocolate milk or mayonnaise. It means oil and coolant are mixing, often due to a failed head gasket.
This is a very expensive repair for any excavator. A used machine with this problem should be avoided. You can identify an internal leak by looking for a few key symptoms.
White Exhaust Smoke: Continuous white smoke from a warm engine suggests coolant is burning in the combustion chamber.
Low Coolant Level: You frequently need to add coolant, but you cannot find an external leak.
Milky Oil: The oil on the dipstick looks frothy or milky, indicating water or coolant contamination.
Finding any of these leaks is a serious red flag. They point to neglect and guarantee expensive repairs in the near future.
Structural Integrity: Spotting Signs of Stress and Failure
The excavator's frame, boom, and arm form its skeleton. This structure handles immense stress during every job. A weakness here is not just a minor issue; it can lead to total failure. You must carefully inspect the structural integrity of any used machine to avoid a dangerous and costly collapse.
Inspect Welds on the Boom and Arm
You should start by examining all the welds on the boom and arm. Look for fresh paint, which can hide recent repairs. Pay close attention to high-stress points where cracks often begin. These areas take the most punishment on any excavator.
The corners of the bucket and where the cutting edge connects.
The points where shanks and teeth attach to the bucket.
The areas around the pins that connect the boom, arm, and hydraulic cylinders.
The base of the boom where it mounts to the machine's frame.
Look for Cracks and Bends in the Frame
Next, you need to inspect the main frame and carbody. Look for visible cracks, bends, or warping in the steel plates. Some cracks are very fine and hard to see. Advanced analysis shows that the exact shape of a weld can create weak spots. Even a perfect-looking weld on a used machine might hide a structural flaw that could lead to future cracks. Any sign of distortion suggests the machine has been overloaded or damaged.
Check for Boom and Arm Drift
Boom and arm drift is a critical test for any used excavator. This test reveals internal leaks in the hydraulic cylinders. To check for drift, you should park the machine on level ground. Raise the boom and extend the arm parallel to the ground. Then, shut off the engine and wait. The boom and arm should not move. A slow downward creep, or "drift," signals worn seals inside the cylinders. This is an expensive repair.
You can measure the drift against a fixed point. Compare your findings to the manufacturer's specifications.
Component | Maximum Allowable Drift | Time Period |
|---|---|---|
Boom Cylinder | 20 mm (13/16 in.) | 5 minutes |
Arm Cylinder | 30 mm (1-3/16 in.) | 5 minutes |
A well-maintained used excavator will show very little to no drift. Significant movement is a clear warning sign of hidden costs.
Identify Signs of Poor-Quality Repairs
You must look for signs of past repairs. A good repair restores the machine's strength, but a poor one creates a new weak point. Bad repairs are a clear warning that the previous owner cut corners on maintenance. You should carefully inspect any area that looks like it has been fixed.
A sloppy weld is one of the most common signs of a poor-quality repair. A professional weld is smooth and uniform, often looking like a neat stack of dimes. You should be suspicious of any weld that looks different.
Warning Signs of a Bad Weld:
Uneven Beads: The weld line is inconsistent in width or height.
Excessive Spatter: Small balls of metal are scattered around the weld area.
Porosity: The weld surface has small holes or bubbles, which indicates weakness.
Cracks: You see fine lines in or next to the weld itself.
Fresh paint is another major red flag on a used machine. Sellers sometimes use new paint to hide cracks, rust, or bad welds. You should look for areas where the paint color or texture does not match the rest of the excavator. Also, check for mismatched hardware. Using the wrong size or grade of bolts for a repair can compromise the machine's safety and structural integrity.
Finding these issues tells you two things. First, the machine had a significant failure in the past. Second, the owner chose a cheap fix instead of a proper one. This mindset often applies to the entire machine, signaling that other hidden problems likely exist. A poorly repaired excavator is a risk you should not take.
Paper Trail: Verifying Maintenance and Ownership History
A physical inspection tells you about an excavator's current state. The paper trail, however, reveals its past. When buying an excavator, you must verify its service and ownership history to protect your investment. A used excavator with a complete and honest paper trail is always a safer bet than one with a mysterious past.
Request and Review Service Logs
You should start by asking the seller for all relevant documents. A professional seller should be able to provide a clear history. Key documents include:
Purchase and ownership papers to prove who legally owns it.
Maintenance and repair records detailing all work done.
Safety and inspection reports.
A complete set of maintenance records gives you a timeline of the machine's life. A detailed log should show the date, the working hours at the time of service, and the specific tasks performed. This information helps you understand how well the previous owner cared for the used machine.
Identify Gaps in Maintenance History
Next, you need to look for what is missing. Gaps in the service history are a major red flag. A lack of records or large jumps in working hours between service entries suggests neglect.
For example, if the log shows an oil change at 5,000 working hours but the next entry is at 7,000 working hours, two years of usage history are completely undocumented. You have no idea if the machine was serviced or abused during that time.
Discrepancies between different documents are also a warning sign. These gaps hide potential problems and make it impossible to predict future reliability.
Cross-Reference Repairs with the Machine's Condition
Finally, you must connect the paperwork to the physical machine. The maintenance records should explain the excavator's current condition. If the log says the hydraulic pump was replaced 500 working hours ago, the hydraulics should feel strong and responsive. If they feel weak, the repair may have been done poorly or another part is failing.
The documented usage history should also match the wear you see. A used machine with low working hours on paper should not have a worn-out undercarriage. If the story from the paperwork does not match the story the machine tells you, you should be very suspicious.
Verify Ownership and Check for Liens
Finally, you must confirm the seller legally owns the excavator and has the right to sell it. A machine with a questionable past can cause serious legal and financial problems later. This step is just as important as inspecting the engine or hydraulics. The ownership papers should clearly match the seller's identity and the machine's serial number.
You must also check if there are any liens on the equipment. A lien is a legal claim on a piece of property to secure a debt. If the previous owner used the machine as collateral for a loan and did not pay it back, the lender can legally repossess it, even from you.
A professional lien search is your best protection. This search helps you:
Avoid inheriting the previous owner's debt.
Determine if the equipment was reported stolen.
Understand the machine's true ownership and usage history.
Confirm the excavator is not being used as collateral for an active loan.
The ownership documents should also align with the machine's physical condition and usage history. For example, the working hours listed on the bill of sale should be consistent with the working hours shown on the hour meter. If the maintenance records show 8,000 working hours but the title shows only 5,000 working hours, you have found a major red flag. This discrepancy suggests tampering or a fraudulent history. Never purchase a used machine without a clear and verifiable title in hand.
A thorough inspection is your best defense when buying an excavator. You can uncover hidden costs by checking the used excavator's engine, hydraulics, and structure. The initial cost of used heavy equipment is only one part of the total cost of ownership. A complete service history for the used excavator helps you predict future reliability.
Investing time in a detailed assessment ensures the price you pay for a used excavator reflects its true value. This protects you from unexpected hidden costs on a used machine.
FAQ
What are good working hours for an excavator?
An excavator often lasts 10,000 to 15,000 hours. You should focus more on maintenance history. A well-maintained, high-hour machine is often a better choice than a low-hour machine with poor service records.
Should I hire a mechanic for the inspection?
Yes, you should consider hiring a qualified mechanic. They have the expertise to spot complex issues with the engine and hydraulics. Their fee is a small price to pay to avoid buying a problematic excavator.
Is new paint on a used excavator a good sign?
You should be cautious. Fresh paint can hide serious issues like cracks, rust, or poor-quality welds. Always inspect freshly painted areas very carefully for signs of underlying damage or repairs.
What is the most important document to check?
You must review the service logs and the ownership title. Service records reveal the machine's maintenance history. The title proves legal ownership and allows you to check for liens, protecting you from legal and financial problems.
