Overall stance
An XJ6 should sit flat and level front-to-back and side-to-side, or very slightly higher at the rear, especially with low fuel load. If sagged to one side – typically the driver’s side – or drooping at the back, the springs are tired. On level ground the bottom of the front subframe should be about 63?8in above ground with most 215 width tyres and 61?4in with 205s.

Body panels
A good XJ should have undistorted panels with even shut lines, and the doors should follow the body contours and not stick out at the corners. Look for filler bulges along the bottom of doors or wings and around the headlamps, arches and sills. Feel the wheelarch returns for rough metal, or double thickness or seams from repairs. Mud-filled seams on sill ends or arches, or around the headlights or lower wing fronts can hide rot, so clean and inspect by torchlight. Front and rear valances suffer badly, and the lower radiator crossmember (visible through the grille) is structural.

Underside and sills
Beware heavy gobs of underseal over poor welding or rusted metal. The fronts of the footwells suffer, as do the sill seams, front and rear jacking points, and the radius arm attachment points. The rear lower quarter-panels around the tanks are often rotten but are detachable. Check for rust in the chassis rails within about a foot of the rear suspension cage mounts, and if the rear screen appears rusty be especially suspicious of rust in the lower rear sill area where the wheelarch joins, as water collects here. If possible, look under the seat cushion for water/rust from a leaky rear screen. The front upper section of the sills is hidden behind the wings, but look from inside the rear edge, past the open door, and check for clues of corrosion, such as packed mud or bubbling at the rear lower edge of the wings.

Bonnet and inner wings
The hinge attachment points rust from inside the box section and this affects shut lines and bonnet closure. There will be tell-tale marks where the bonnet has hit the top of the wings if it has closed crookedly in the past. Typically, the left-side hinge area is worst affected where it takes the strain of the bonnet prop mechanism. Inner headlights don’t rust as badly as the outer wings. Inner wings should be free of corrosion at the front bottom corner where they meet the chassis rails (under the washer bottle especially, where it tends to stay damp) and along the top edge where the wings attach. Chassis rails should be undamaged and not creased or patched from an accident. Top shock absorber mounts can be checked, as can the battery tray area.

Boot lid
Rust strikes from inside, either through seal leakage, condensation, or leakage via holes from missing or poorly-fitted badges. Higher-spec models have a one-piece lid liner, whereas others use stick-on panels between the reinforcement stiffeners. The lower edge should not strike the body, and the shut lines should be even all around.

Floors
The carpets and underlay must be lifted to check the inner sill to floor seams, rear bulkhead seams, and front footwells. Check seat and safety belt attachments points. The foam strips in the channels are great sponges so press them to feel for dampness which may mean the car was dried out in a hurry for your inspection.

Doors
Check door gaps and feel along the bottom edges – even re-skinned doors may have bad frames. Coupé doors are especially vulnerable to knocks as they open so wide, and they are expensive to repair because good secondhand replacements are scarce. Use your eyes, hands and your bodywork probe to check door apertures for rust in the corners of the openings at the base of the A B and C pillars. Door drop is an issue for driver’s doors, especially on the coupés. Doors should fit flush and close with a thud not a clang. Door cards should be flat and even, with undamaged armrests and pockets securely attached. Check that the front opening quarter-lights open and seal properly on S1 cars, and that any remote control mirrors and manual or electric windows and central locking work. Door perimeter seals should be intact, and can be checked for fit by closing the door onto a sheet of paper in various positions.

Petrol tanks and pipework
The petrol tanks frequently rust from underneath, and the pipes running into the boot space corrode. Look for signs of leakage or lifted paintwork below the car. Inside the boot, remove the spare and undo the fuel pump cover to check for correct anti-vibration-mounted fuel pumps and leak-free feeds and returns (fuel-injected cars). Wiring should be clamped firm, not hanging loose, and well insulated rather than cracked or with bare strands showing. The fuel filter towards the front on the right should be solidly mounted too, with no signs of weeping, chaffed pipework, or heavy fuel smells. While the fuel pump cover is off check the electric aerial motor, drain and relay on early cars. Check also the welded seam between the rear valance and boot floor, as this can split.

Vinyl roof/sunroof/convertibles
Many Daimlers and Vanden Plas models of the seventies came with a vinyl roof, and a small number were made into two- or four-door convertibles by firms such as Lynx and Avon. In all cases check for tears or splits or separated seams and other damage. Converted soft tops use either a large fold-down hood or a roll-down landau-type top with door and window frames left intact. A Webasto-type folding sunroof should be checked for seal and tension, and metal reinforcing rods protruding through the sides. Electric sunroof checks include the seal around the hatch and good drains – as well as proper functioning. Factory sunroofs from this era only have a sliding action, no tilt.