Buying a Used Excavator: What to Check Before You Buy

A used excavator can be one of the best value buys in plant, but only if you know what you are looking at. Two machines of the same make, model and year can be worlds apart once you look at the undercarriage, the pins and the hydraulics. This guide covers what to check on a used digger before you hand over any money, whether you are after a micro, a mini, a midi or a full size tracked machine.

Pick the right size of machine first

It is easy to fall for a good looking machine that is wrong for the work. Think about the jobs you do most often, the ground you work on, how you will move the machine between sites and what attachments you already own.

Micro and mini excavators suit landscaping, footings, drainage and tight access jobs. Browse used mini excavators for sale if you tow your own kit on a plant trailer.
Midi excavators in the 6 to 10 tonne range are a popular middle ground for groundworkers and farm contractors. See current used midi excavators.
Full size tracked excavators are for bulk earthmoving, quarry and demolition work, and need a low loader to move. Our full range of used excavators for sale covers all sizes.
Wheeled excavators are handy for roadworks and jobs where the machine travels between work areas. Have a look at used wheeled excavators.

Check the pin sizes and quick hitch type too. If your buckets and breakers will not fit, the cost of new attachments soon eats into any saving.

Undercarriage: the most expensive part to get wrong

On a tracked machine the undercarriage takes a beating, and it is often the costliest thing to put right. Take your time here.

Sprockets: look at the teeth. Sharp, hooked or pointed teeth show heavy wear.
Rollers and idlers: check for flat spots, oil leaks from the seals and rollers that do not turn.
Track chains and pads: look for stretched chains, cracked or bent pads and worn grousers. On rubber tracked minis, check for cuts, exposed steel cords and missing lugs.
Track tension: very slack tracks can point to worn components or a leaking adjuster.
Track frames: look for cracks and signs of welding, especially around the idler and the travel motors.

Ask the seller how much life is left in the undercarriage and whether any parts have been replaced recently. Receipts are worth more than promises.

Boom, dipper, pins and bushes

Lift the arm and look along the boom and dipper for cracks, fresh welds and plating. Repairs are not always a deal breaker, but you should know about them and why they were needed. Fresh paint in one area is worth a question.

Wear in the pins and bushes is very common. With the bucket on the ground, ask someone to gently work the controls while you watch each pivot point: the boom foot, the boom to dipper joint, the dipper to bucket linkage and the quick hitch. Clunks or visible movement mean wear. Check that grease points are taking grease, because a dry machine usually tells you how it has been looked after.

Hydraulics and slew

Start the machine from cold if you can, as some faults hide once the oil is warm. Then run every function.

Rams should move smoothly and hold position. Lift a full bucket, hold it off the ground and watch for the arm creeping down.
Look along the rams for scored or pitted chrome and for oil around the seals.
Check hoses for chafing, bulges and weeping fittings.
Slew the machine both ways. It should be smooth, with no knocking or excessive play in the slew ring.
Track the machine forward and back in a straight line. It should not pull to one side.
If you run a breaker, tilt bucket or tiltrotator, check the auxiliary circuits work properly.

Engine, cab and electrics

Listen for knocks and look for heavy smoke on start up and under load. Check the oil and coolant for any sign of mixing, and look around the engine bay for leaks. Blow-by from the breather can point to a tired engine.

In the cab, check every gauge, warning light, wiper and light works. Look at the seat, pedals and joysticks: heavy wear here should match the hours shown. Make sure safety items such as the seat belt, the isolator and the hydraulic lock lever all work.

Hours, service history and paperwork

Hours matter, but they are only part of the story. A well maintained machine with higher hours can be a better buy than a neglected low hour one. Ask for service records and check whether major items such as the undercarriage, rams or the engine have been replaced.

Before you buy, also check:

The serial number on the machine matches the paperwork.
Whether the machine has any outstanding finance. A finance check is a small cost compared with losing the machine.
Whether it is registered on a plant security scheme, and that the details match the seller.
That a lifting machine has a current thorough examination certificate if you plan to lift with it.
Exactly what is included: buckets, hitch, breaker pipework and any spare parts.

Buying from a dealer or a private seller

Buying from an established dealer usually gives you more comfort on history and paperwork, and some will offer a warranty or after sales support. Private sales can be good value, but you will need to do more of the checking yourself. Either way, see the machine working before you pay, and if you are not confident, take a mechanic or an experienced operator with you.

Do not forget transport. A mini may go on your own trailer, but larger machines need a low loader, so get a delivery price before you agree a deal. Our guide to low loader transport and moving plant covers what to ask.

Find your next excavator on Plant And Tractor Trader

Plant And Tractor Trader lists used excavators from dealers across the UK and Ireland, from micro diggers up to big tracked machines, plus buckets, breakers and attachments to go with them. You contact the seller direct, with no middleman.

Selling excavators? Dealers can advertise plant and machinery on Plant And Tractor Trader, with unlimited listings for £500 + VAT for 12 months or a one-off advert for £150.

For help finding a machine or to talk about advertising, call or WhatsApp us on 07470 093663.