How to inspect a classic car before you buy

Do the homework at home. Read the owners' club or specialist buying guide for the model, because every car has its own weak points and the club knows them. Put the registration into the free DVLA vehicle enquiry, which shows the year of manufacture, the date first registered and when the last log book was issued, and into the free MOT history service, which in Great Britain goes back to 2005 and shows the mileage at each test and every advisory. A mileage that goes backwards, or the same corrosion advisory repeated test after test, tells you a great deal before you have seen the car. A gap of years is worth asking about, although many cars over 40 years old no longer need an MOT, so a recent gap is not suspicious on its own. Decide the most you will pay, all fees included, before you go.

Take what fits in your pockets, because Mathewsons does not allow handbags or large bags at its viewings, and check the rules of any other saleroom before you go: a small torch, a magnet wrapped in a soft cloth so it cannot scratch the paint, a rag, a pair of thin gloves, a notebook, and your phone to photograph numbers and anything you want to study later. If you have a paint depth gauge, bring it. Go in daylight and in dry weather if you can, because rain and artificial light hide ripples and poor paint. Better still, take someone who knows the model; the owners' club may be able to put you in touch with a member who can help.

Before you touch anything, stand back and walk all the way round. A car that sits low at one corner or one end may have tired springs. Then crouch at each corner and look along the flanks with the light behind you. Ripples and dips can mean filler, and a texture like orange peel can mean the car has been repainted. Compare the colour of adjacent panels in good light; a door that is a shade different has probably been painted on its own.

The numbers on the plan show where to look on almost any classic:

1. Front panel and valance.
2. Front wings and the inner wings under the bonnet.
3. Engine bay and bulkhead.
4. Windscreen surround and scuttle.
5. Door pillars and hinges.
6. Doors, especially the bottom edges.
7. Sills.
8. Floors and footwells, from inside and underneath.
9. Rear wheel arches and the panels behind the doors.
10. Boot floor and spare wheel well.
11. Rear valance, bumpers and exhaust.
12. Chassis rails, crossmembers and suspension mountings, underneath.
13. Wheels, tyres and brakes, at each corner.
14. Interior, roof or hood, and the instruments.

Check the gaps around the doors, bonnet and boot lid. They should be even all round and match side to side. Wide or uneven gaps can mean poorly fitted replacement panels, a door that has dropped, or a body that has been distorted by an accident or by rot. Some cars were never precise when new, so learn what the model's gaps should look like.

Open each door and lift it gently at the open end. A door that drops or needs lifting to latch has either worn hinges, which are cheap to put right, or a weak pillar or a sagging body, which is not.

Look for overspray on rubber seals, chrome, badges and glass, a sure sign of a respray, and ask yourself why it was resprayed. Look closely at bubbles in the paint, especially along the bottoms of doors, wings and sills: a bubble is rust coming through from behind, and there is usually more rust behind it than the bubble suggests.

Run the cloth-wrapped magnet over the lower panels, the wheel arches and the sills. Where it pulls weakly or slides off a steel panel, there is probably filler underneath. A magnet tells you nothing on aluminium or glassfibre, so know what your car is made of. A paint depth gauge does a similar job; readings that jump from panel to panel suggest a repaint.

Do not poke holes in someone else's car, but press firmly with your thumb on the bottoms of sills, arches and floors. Good metal is rigid. Metal that gives, crackles or crunches is rotten.

Rust is the one fault that is slow, costly and can be dangerous, and bodywork is usually the most expensive part of a restoration. It starts where water and dirt sit and cannot dry: sills, floors and footwells, the bottoms of doors and wings, wheel arches, the windscreen surround, the boot floor and spare wheel well, and on a car with a separate chassis, the chassis rails and the outriggers that carry the body.

What matters most is whether the rust is structural. The MOT test treats as critical the load-bearing structure that the brakes, steering, suspension and other tested parts such as seat belts are mounted on, together with any load-bearing or supporting panels within 30 centimetres of those mountings. Rust in those areas fails if it has made a hole or if the metal does not feel firm under finger and thumb pressure, and repairs there made with body filler, brazing, solder, glassfibre or adhesive are not accepted. Many cars over 40 years old no longer need an MOT, but the test is still the best public guide to what counts as structural. Cosmetic rust in a wing top is a nuisance; structural rust in a sill or a chassis rail is the price of a car.

Whether the sills carry the car's strength depends on the design. On some cars they are a cover; on many monocoque cars they are a main part of the structure, and repairing them properly is a major job. The owners' club guide for the model will tell you which.

Be wary of fresh underseal or paint underneath. It may be honest protection, or it may be hiding a poor repair: if paint or underseal hides how a repair was done, the MOT tester passes it and records an advisory, so a new MOT certificate does not prove what is under fresh underseal.

At a viewing you cannot put the car on a lift, so kneel or lie on a mat or an old coat if the staff allow it, and use the torch. Look from the side; never get under a car that is held up only by a jack, and never jack up a car at a viewing yourself. Look at the floors, the sill undersides, the chassis rails or the box sections that do their job, and the points where the suspension and the rear axle are mounted. Look for patches welded over patches, holes, crusty flaking metal, and wet or oily areas. Follow the brake pipes and the fuel lines: steel lines corrode, and rubber hoses crack with age. Note every leak and where it comes from.

Not every classic is steel. Aluminium panels do not rust in the same way, but they corrode where they touch steel, and corrosion and blistering paint at those joints are worth looking for on cars such as Land Rovers, Morgans and AC 2-Litres. Glassfibre bodies do not rust, but look for star-shaped cracks in the gelcoat, particularly around hinges and other stressed areas, and remember that the steel chassis underneath can rot unseen. Some cars, including Morgans and the MG T-types, have bodies built on a wooden frame; soft or rotten timber shows as doors that will not shut properly and body panels that move, and rebuilding the frame is a specialist job.

Ask for the engine to be started from cold, and feel the bonnet or the radiator first to make sure it has not been warmed up before you arrived. A cold start shows faults a warm engine hides. At an auction viewing, ask the staff whether the car can be started and when; some salerooms will do it with staff present, but you will not normally be able to drive it. If a car has been laid up for a long time, starting it without preparation can damage the engine, so leave that decision to the staff and do not press for it.

Watch the exhaust as it starts. Thin white vapour that clears in a few minutes is condensation and is normal. Blue smoke is oil being burnt, from worn rings, bores or valve guides. Thick white smoke that does not clear, often with a sweet smell, usually means coolant is being burnt, often because of a failed head gasket. Black smoke means the engine is running rich.

With the engine off, pull the dipstick: the level should be right, and the oil should not look milky or grey. Even fresh oil darkens quickly, so black oil alone is not a reason for alarm, but thick, sludgy or gritty oil points to neglect. Look under the oil filler cap: a heavy creamy, mayonnaise-like deposit can mean oil and water are mixing, often through a failed head gasket, although Practical Classics says a tiny amount may be nothing to worry about. With the engine cold, check the coolant level and colour, and look for oil floating in it. Never open the radiator or expansion tank cap on a warm engine.

Look for leaks. Hagerty's David Lillywhite says a little weeping is normal on many older engines, but dripping oil is not acceptable on anything from the 1950s on. Look at the hoses and the radiator, and listen once it runs: a light tapping that changes with engine speed is often valve clearances, but a deep knock or rumble from low in the engine points to worn bearings. Check that the engine number matches the log book.

If the car can be driven, watch the temperature gauge. Hagerty UK advises that it should not go above about two-thirds, even in traffic, and that a temperature that keeps creeping up is a reason to walk away.

Most of the drivetrain needs a road test to judge properly: a clutch that slips or judders, a gearbox that jumps out of gear or crunches, an overdrive that will not engage, and a back axle that whines or clonks. At a viewing you can still look for oil leaks around the gearbox and the axle, ask whether you may check that the gear lever moves through the gears with the engine off and the handbrake on, and grip the propshaft to feel for play in the universal joints. On an automatic, ask the staff whether you can see the fluid: healthy fluid is usually red or pink, and dark brown fluid needs a specialist's look. The level is normally checked with the engine warm and running, so a cold reading tells you little.

Press down hard on each corner and let go. The car should settle almost at once, after no more than one or one and a half bounces; if it keeps bouncing, the dampers are tired. Look for leaking dampers and perished rubber bushes, and on older designs ask whether the suspension has been greased or oiled as the maker intended, because some front suspensions wear quickly without it.

With the front wheels pointing straight ahead and on the ground, turn the steering wheel gently each way until the road wheels just start to move. The MOT limits, measured at the rim of a 380 millimetre (15 inch) steering wheel, are 13 millimetres on a rack and pinion system, or more where the steering column has several joints, and 75 millimetres on a steering box. More than that is an MOT failure and means wear, and a rack in good order should have almost none. Checking the wheel bearings and joints properly means lifting each wheel clear of the ground on a jack with axle stands, so leave that to an inspector, or to a private sale where it can be done safely.

Look at the brake pipes, hoses and fluid. Brake fluid absorbs water over time and needs changing every two or three years; dark fluid suggests it has not been. Ask what fluid the system uses: silicone (DOT 5) fluid must not be mixed with ordinary fluid, and a system has to be fully converted to use it.

Read the date code on every tyre: the last four digits of the DOT code give the week and year it was made, so 2319 means the 23rd week of 2019. A three-digit code means the tyre was made before 2000 and should be replaced. Classic tyre specialists advise replacing tyres at ten years old regardless of the tread, and a car that has stood will often need a full set. Look for cracking in the sidewalls. Check the tyres match: it is illegal to mix tyres of different construction on the same axle, or, on a car with two axles, to fit crossply or bias-belted tyres on the back with radials on the front. On wire wheels, look for loose or broken spokes and worn splines.

Try everything, with the staff's permission at an auction: lights, indicators, wipers, horn, heater fan, every gauge and every switch. Look behind the dashboard and under the bonnet for bodged wiring, insulating tape, burnt or melted wires, and extra cables added over the years. Many British cars built up to the mid or late 1960s are positive earth; check which battery terminal is bolted to the body before anyone connects anything. Check the seats, carpets and headlining, and lift the carpets if you can: wet carpets mean water is getting in, from a perished seal or sometimes a leaking heater, and water left inside rots the floor. Missing or damaged trim can cost more than you expect, and on some models it is no longer made. On an open car, look at the hood, its frame and the rear window.

Check the log book first. A genuine V5C has a "DVL" watermark, and the government warns that forms with serial numbers between BG8229501 and BG9999030, or between BI2305501 and BI2800000, may be stolen. Find the chassis or VIN plate and any stamped number on the car, and the engine number, and check that they match the log book. Photograph them.

The date first registered and the year of manufacture can legitimately differ, for example on an import. A Q plate means DVLA could not confirm the car's age or identity, or that it was built using new or replica parts. A classic not taxed since 1983 may never have been put on the DVLA computer, and form V765, endorsed by an owners' club, can recover its original number where there is evidence linking the car to it; a number recovered this way cannot be transferred to another car.

Since 26 August 2025, owners have not needed to tell DVLA about like-for-like repairs and restorations, as long as the car still looks as it was made and the log book details are unchanged, although replacing a chassis, bodyshell or frame must still be reported. A significantly structurally modified car can usually keep its original VIN and registration, but the keeper must tell DVLA, and the log book will say it has been modified from the manufacturer's specification. If a car has had a new bodyshell or chassis, ask for the DVLA paperwork showing it was declared and the number restamped.

A good history file has invoices with the car's registration or chassis number on them, old MOT certificates, and photographs of any restoration. Be cautious of a car described as fully restored with nothing to show for it. Paid history checks are worth doing, but they can miss old write-offs and copied identities on classics.

A heritage certificate, from the British Motor Museum for marques such as Austin, Morris, MG, Triumph, Rover and Land Rover, or the Jaguar Daimler Heritage Trust for Jaguars and Daimlers, tells you how a car with that chassis number left the factory. It does not prove the car in front of you is that car; the Trust itself says its certificate is not confirmation of identity, provenance, originality, present condition or ownership. It is only useful if the numbers on the car match it. Treat "matching numbers" claims the same way: chassis and engine number plates can be bought or copied, so look for the evidence behind the claim.

Be especially careful with the most valuable versions of ordinary cars, which are the ones most often copied: a basic Mini dressed as a Cooper S, or a lesser model wearing the badges of a rare one. A replica described honestly is fine; one sold as the real thing is fraud.

Mileage on an old car is rarely provable. A five-figure odometer may have gone round. Mathewsons lot pages, for example, say "Please refer to the photos for mileage showing", which means the auction house is not stating the mileage, and any figure in the vendor's notes is the vendor's own claim. Treat the mileage as unwarranted unless the history file proves it.

Read the catalogue description carefully, and remember who wrote it: much of it is the vendor's own words, and Mathewsons lots are "sold as seen and without any warranty implied or given", so you must satisfy yourself about a lot's description and condition before you bid. Phrases such as "easy restoration", "barn find" or "recently recommissioned" describe a hope, not a condition. Ask the staff anything you need to know and whether the car can be started.

The AA's vehicle inspections are for vehicles up to 20 years old, and the RAC's basic inspection excludes cars over 10 years old, so neither is designed for classics. If you want a professional opinion, use a marque specialist or an independent classic car inspector, and check with both the inspector and the auction house that they can attend before the viewing week ends.

Then put a price on what you found. Your ceiling is the hammer price plus the buyer's commission and any VAT, the cost of getting it home, the cost of putting right what you saw, and a margin for what you could not see. If the sum does not work, let the car go: a Mathewsons sale has up to 900 lots. Our how-to-buy page covers bidding and fees, and our getting-it-home page covers the drive home.

The checks above apply to any classic. Each model also has its own weak points, and these guides on our sister sites go through them in detail: