What to look out for:
Rust has taken its toll on unrestored steel-. bodied cars: virtually every square inch of metalwork is susceptible to the vagaries of ‘tin worm’. Pay particular attention to the wheel arches, windscreen pillars, the front wings around the headlamps, and both the front and rear inner wings. The only good news is that there is an army of specialists who can provide replacement panels.
Chassis: Substantial steel chassis frame comprises longitudinal and transverse cross members; box sections are all capable of trapping moisture and causing serious corrosion. Comparatively simple construction means that repairs are not outside the scope of competent DIY enthusiasts, but access is not good with the body in situ.
Engine: XK twin-cams are notorious oil burners, but a well maintained and regularly serviced unit will go on almost indefinitely — Jaguar’s record-breaking run around Montlhery in 1952 when Moss, Fairman, Hadley and Johnson averaged over 100mph for seven days and nights without one major upset proves that.
Electrics: The majority of electrical components were manufactured and supplied by Lucas, and don’t, as a rule, cause any major headaches. It is as well to check that restored cars have been properly rewired and that the main electrical components have either been replaced or reconditioned. Early cars were fitted with twin six-volt batteries, but don’t let that put you off — they work perfectly well if not neglected.
Hood: Being unlined on the inside, roadster hoods are fairly simple in construction, and this is reflected in the cost of replacements. On the other hand, the double-skinned items fitted to drophead coupes are much more substantial, and replacing a damaged one could set you back the cost of a perfectly serviceable five-year-old XJ6. As with all ‘ragtops’, the hood is a prime target for vandals armed with a Stanley knife.
Bodywork: Poor fitting doors — a common enough sight on restored XKs — may indicate a generally poor restoration. Never accept a vendor’s word that everything’s been done properly; ask to see photographic evidence or video footage. Items of trim are readily available from specialist suppliers.
Brakes: Drums fitted to 120s and 140s are prone to fade, but set up and adjusted properly, (which is only rarely) they can be as good as any. Discs fitted to 150s are durable and work well, but pad wear is generally high.
Transmission: Four-speed manual gearboxes are superb to use — slick, positive changes as fast as you like — and are very durable. Some gearbox components are becoming difficult and expensive to obtain. Overdrive units should work smoothly and are equally long-lived. And the same applies to the rear axle. Automatic gearboxes can become ‘clunky’ on high-mileage cars — but who wants an auto ‘box in an XK anyway?