How to Inspect a Used Excavator Before Buying It

Check the undercarriage, the play at every pin and bushing joint, and the hydraulic cylinders before you look at paint or the hour meter — those three decide most of the repair bill. A cheap machine with a finished undercarriage and slack pins can cost as much to put right as a good machine costs to buy.

The order below is deliberate. Work from the ground up, because the parts that carry the machine wear out first and are the most expensive to replace.

Why does the undercarriage decide the deal?

Industry estimates commonly put the undercarriage at around half of a crawler machine's lifetime repair bill. It is also the easiest area to inspect honestly, because wear is visible and measurable without opening anything.

How do you measure undercarriage wear in the yard?

• Bushing outside diameter. Measure across the bushing on both tracks with a caliper. A new chain has a known figure; the difference is the wear.
• Sprocket teeth. Sharp, pointed tips or a hooked tooth face mean the sprocket is finished, and a new chain on it will die early.
• Roller flanges. A flange worn thin and sharp, or a roller that rocks on its shaft, is due for replacement.
• Grouser height. Compare shoe bars against a new shoe; rounded, polished grousers are past their working life.
• Five-pitch measurement. A tape over five pitches on a clean, tensioned section shows how far the chain has stretched.

Compare the left and right track. A machine that has spent its life turning one way, or working on a slope, will have one side noticeably further gone, and that tells you how it was used.

How much play is acceptable in the pins and bushings?

A new joint has almost no perceptible movement. Put the bucket flat on the ground, lift it just off the ground, and rock it by hand while watching each joint in turn: bucket to link, link to stick, stick to boom, boom to carbody. Once you can see two or three millimetres of relative movement at a joint, the bucket bushing and bucket pin are due, and the bore in the boss is probably going oval with them.

Use a pry bar for a second opinion, and look for the signs of a previous repair: weld beads around a boss, a bore that has been line-bored and fitted with an oversize pin, or a pin held in with a makeshift bolt instead of the correct retainer. Check the retaining hardware on every pin — missing bolts, spiral pins or end plates mean pins are walking, which is a safety issue as well as a wear issue.

What do the hydraulic cylinders tell you?

Look at the rod, not the barrel. A wet ring of oil and dust at the wiper means the rod seal is passing, and a scored or flaking chrome rod will destroy a new seal in a few hundred hours. Check for a bent rod by running the cylinder fully out and watching whether the rod stays centred in the gland. Then look at the hoses: chafed outer covers, weeping ferrules, and date codes older than the machine's last major service all belong on the list.

Oil condition is worth the ten minutes. Dark, burnt-smelling oil, or oil with visible metal, points to a pump or motor problem that no amount of new seals will fix. If the seller will not agree to an oil sample, treat that as information too.

Which cracks matter and which are routine?

Cosmetic dents in a bucket are normal. Cracks that matter run from a pin bore outward: boom foot bosses, the stick nose, bucket ears, and the boom cylinder mounts. A crack repaired properly — ground out, welded, plated and documented — is acceptable on an older machine. A crack that has been painted over, or one radiating from a bore, is a structural problem and a negotiating point at best.

Walk the carbody and the track frame as well. Cracks in the X-frame or around the final drive mounting are expensive, and they are easy to miss when you are looking at the boom.

What does the hour meter not tell you?

It does not separate idle hours from working hours, and on an older machine it may not be the original monitor. Judge the meter against the wear you have already measured: a machine showing 6,000 hours with a finished undercarriage has either worked hard in abrasive ground or has been round the clock. A machine with new tracks and a worn-out bucket has usually been prepared for sale rather than maintained.

What should you budget for parts immediately?

Most used machines need a second delivery of consumables within the first season: a set of pins and bushings for the working joints, a set of bucket teeth and any worn adapters, and a cutting edge if the bucket lip is thin. Price that before you agree a number, because it is the difference between a machine that earns and a machine that sits.

What belongs in the inspection record?

Photograph every joint and every measurement with the tape or caliper in frame, note the figures, and keep them. When a joint starts knocking six months later you will want to know whether it was already worn when you bought it, and a dated record settles the argument with a seller or a workshop.

What it means for a parts order in practice

Production time does not move. Machining, heat treatment and packing run at the same pace whichever port the container leaves from. What a shorter inland leg changes is the buffer a supplier needs between finishing an order and handing it to the carrier, and at the margin how much working capital sits in a container on a truck.

For the buyer, the response is unchanged: plan stock against ocean transit plus clearance, not against the inland leg, and ask for the port and the sailing date rather than a single lead-time number. The parts themselves — bucket pins and bushings, track chains, bucket teeth — are priced by steel grade and machining hours, not by which river they floated down.

That regional split matters for spare-parts planning. Mature markets in Europe are growing slowly, while the fastest-growing destinations are markets where machines work long hours in abrasive conditions and where the dealer and service network is thinner — exactly the profile that generates high wear-parts consumption. Trade-press analysis attributes a large share of African excavator demand to mining, and mining duty is brutal on undercarriage and on ground-engaging tools.

What should buyers and distributors plan for?

Stock the models that are actually in the field, not the models in the press release. On the evidence of the last few years that means the mainstream 20–30 tonne classes and the household names built around them — PC200 and PC300 class machines, the 320 and 330 class, the EX200 class, the R210 class and the DX225 class — plus the undercarriage groups that fit them. Those are the machines absorbing pins, bushings and track components in volume.

Do not build stock around electric-specific parts yet. At 0.6% penetration there is no volume aftermarket, and the common parts on those machines are the same parts you already carry.

Finally, plan for the replacement cycle, not just the new-machine market. Chinese trade-press analysis puts the domestic replacement cycle at roughly eight years, and with domestic sales now rising on the back of equipment replacement and emission-standard upgrades, a large second and third-owner population of machines is coming into its maintenance-heavy phase. That is the cohort that buys the most wear parts per machine — and it is a diesel cohort.