Check the paperwork before the machine: the serial plate should match the documents, the seller should prove ownership, and stolen-plant and outstanding-finance checks should come back clear. Then check the hours against the wear, the service history, the undercarriage or tyres, pins and bushes, hydraulics, slew or tipping gear, engine, ROPS and seat belt, and finish with a test run from cold. The checklist below comes from the parts desk at SM Plant Sales in Rugby.
What paperwork and ownership checks should I do?
Do these first: a machine the seller cannot prove is theirs is not worth buying at any price.
- Serial plate: present, readable, not loose, re-riveted or painted over, and matching the invoice and any documents.
- CESAR: many machines carry CESAR marking (the UK construction equipment registration scheme), with tamper-evident labels and a registration plate. Check the registration and look for removed labels.
- Stolen plant: check the serial number against a stolen equipment register, such as TER (The Equipment Register).
- Finance: ask whether any finance is outstanding, and use a finance check service, much like an HPI check on a car. A machine with finance owing may still belong to the lender.
- The seller: get a full name and address, see the machine where it is normally kept, and get a proper invoice.
Walk away from a price well below similar machines, a cash-only deal, missing paperwork or a hidden serial plate.
How do I know if the hours are genuine?
Treat the hours meter reading as a claim to check: meters fail and get replaced. Wear on the seat, pedals, levers, steps and pins should match the hours, and dated service records with the hours written on each entry are the evidence you want.
If the meter has been replaced, ask when and at what reading.
What service history should I ask for?
- Dated records of oil and filter changes at the intervals in the operator’s manual, with parts invoices.
- Details of any major repairs, such as an engine, hydraulic pump, slew ring or transmission.
- For excavators used for lifting, LOLER thorough examination reports.
No history does not always mean a bad machine, but it does mean pricing in a full service straight away.
What should I check on a used mini excavator?
Undercarriage
Undercarriage parts are a major wear cost on a tracked machine. Check rubber tracks for cuts, cracking and exposed steel cords; sprocket teeth for hooked tips; idlers and rollers for leaks or flat spots; and the track frame for cracks.
Pins and bushes
With the engine running and the bucket on the ground, gently operate each service while someone watches the pivots. Visible movement or knocking at the boom foot, dipper, bucket linkage, swing post or dozer blade means worn pins and bushes.
Hydraulics
Look for leaks at rams, hoses, fittings and the pump, and for chafed hoses. Ram rods should be smooth: scoring or pitting damages seals. For a drift test, raise a full bucket, hold it, and watch whether the boom creeps down. Every service should run smoothly and strongly once warm.
Slew
Slew both ways and stop: the upper structure should stop cleanly without knocking. Use the boom to lift the tracks slightly off the ground and watch the gap at the slew ring; obvious rocking points to a worn slew bearing.
Hitch, cab and safety
The quick hitch should lock fully, with its safety device working. Check the ROPS or TOPS label is present and the frame has no cracks, welds or drilling, then check the seat belt, the hydraulic isolation lever, the travel alarm, beacon and lights.
What should I check on a used site dumper?
Chassis, steering and brakes
Check the articulation joint for play, cracks and weld repairs, and steer from lock to lock. The parking brake should hold the machine on a slope, and the service brake should stop it cleanly.
Skip and tipping gear
Check the skip pivots and rams for play and leaks, and tip a full load if you can. The skip lock must engage. On swivel dumpers, check the swivel ring for play and the swivel lock; on high-tip dumpers, check the lift arms and pivots.
Tyres and transmission
Look for cuts, sidewall damage and mismatched tyres, and check the wheel nuts. A hydrostatic drive should pull smoothly both ways without hesitation; on a manual gearbox, gears should select cleanly and the clutch should not slip.
ROPS, seat belt and visibility
The ROPS should carry its label, with no cracks, welds or drilling, and folding ROPS pins and locks should work. The seat belt must buckle, retract and be free of fraying. Check the lights, beacon, horn and mirrors, and the camera if fitted. A Mecalac dumper built before the 2025 EN 474 update will not have the side mirrors, inclinometer and front camera added then.
What engine checks apply to both?
- Ask for a cold start, and feel the engine first to check it has not been warmed up.
- Some smoke on a cold start is normal. Blue smoke that stays suggests burning oil; white smoke that does not clear once warm can mean coolant getting in.
- Milky engine oil, or oil in the coolant, is a warning sign.
- Check for leaks, worn belts and a blocked radiator, and that every warning light goes out.
How should I test-drive a used digger or dumper?
- Start from cold and watch the gauges as it warms up.
- Run every function on its own, then two or three together.
- On an excavator, track in a straight line in both speeds, slew both ways and dig if you can.
- On a dumper, drive loaded if possible, steer lock to lock, test the brakes, and tip and return the skip.
- Once warm, check again for leaks, listen for new noises and check the hours meter moves.
Used plant checklist
| Area | Check | Warning signs |
|---|---|---|
| Paperwork | Serial plate, invoice, CESAR, stolen and finance checks | Missing or altered plate, no proof of ownership |
| Hours | Meter against wear and records | Low hours with worn pedals, seat and pins |
| Service history | Dated records with hours | Long gaps, no oil and filter changes |
| Undercarriage | Tracks, sprockets, rollers, idlers | Exposed cords, hooked sprockets, leaking rollers |
| Pins and bushes | Boom, dipper, bucket, swing post, blade, articulation joint | Visible play, knocking, dry pins |
| Hydraulics | Rams, hoses, drift test | Leaks, scored rods, boom creeping down |
| Slew | Slew ring and motor | Knocking, rocking, uneven stopping |
| Skip | Pivots, rams, locks, swivel ring | Play, leaks, a lock that does not engage |
| Engine | Cold start, smoke, oil, coolant | Hard starting, persistent smoke, milky oil |
| Tyres and brakes | Tread, sidewalls, parking brake on a slope | Cuts, mismatched tyres, a brake that does not hold |
| ROPS and seat belt | Frame, label, pins, belt | Cracks, welds, missing label, frayed belt |
| Lights and alarms | Lights, beacon, horn, travel alarm, camera | Anything not working |
What should I do after buying a used machine?
Give it a full service straight away: engine oil, all filters, hydraulic oil, and grease at every point. Our filters range lists 207 filters, and Parts by machine covers 224 machines, including 56 Volvo excavator models, 63 Wacker Neuson machines and 28 Mecalac, Terex and Benford dumpers and rollers. Our guide to finding the right part explains what to send.
For repairs, see our servicing page. For a dumper, our daily checks guide sets out the routine. Still deciding? Read new or used plant: how to choose or see our used plant stock.
Questions
What is a CESAR check on plant?
CESAR is the UK construction equipment registration and marking scheme: registered machines carry a registration plate and tamper-evident labels. Checking the registration helps confirm the machine is what the seller says it is.
How can I check a used digger or dumper is not stolen?
Check the serial number against a stolen equipment register such as TER, check any CESAR registration, and make sure the serial plate matches the paperwork. Also run a finance check, as a machine with finance owing may still belong to the lender.
What are the signs of worn pins and bushes?
Visible movement or knocking at the pivots when you gently operate each service with the bucket on the ground. Dry, ungreased pins and oval holes in the bosses are further signs.
Should I get a used machine inspected before buying?
If you are not confident checking it yourself, yes. An independent fitter’s inspection can cost less than a single hidden repair. More answers are on our FAQ page.
Can SM Plant Sales supply parts for a used machine I have bought?
Often, yes: SM Plant Sales has 2,630 parts online and 224 machines in its finder, across Volvo, Wacker Neuson, Mecalac, Terex, Benford, Thwaites and CompAir. Send the make, model and serial number to the parts desk on 01788 555377 or WhatsApp 07989 556457.