82 We follow the experts as they strip and rebuild Jaguar’s legendary XK straight-six, double overhead cam engine.
Follow our two-part guide to stripping and rebuilding a Jaguar XK engine
JWORDS AND PHOTOGRAPHS ROB HAWKINS aguar’s six- cylinder twin- cam XK was the company's flagship engine for almost half a century, powering anything from an E-type and Mk2 to an XJ6, Daimler 420S limousine and even a range of armoured vehicles. Almost 700,000 of these engines were manufactured between 1948 and 1992 as a 2.4-, 3.4-, 3.8- or 4.2-litre straight-six, so there was a time when they were readily available both brand new and in scrap Jags and Daimlers, but that’s now a distant memory. Instead, a rebuild is often the only option for a leaking or smokey XK engine, but fortunately spares are readily available, along with a number of upgrades. The bad news is that a rebuild is rarely cheap, but then again many of the cars they are fitted to are similarly expensive.
Stripping an XK engine doesn’t require a wide range of specialist tools, but it does help to have a substantial engine stand and a decent crane to lift it into position and help with removing the cylinder head. That cylinder head can seem as though it has been welded to the top of the engine block, but often you will find that it simply needs a few hours suspended from an engine crane to help persuade it to let go.
The following steps were photographed at Jaguar restoration specialist P&K Thornton
Restorations, showing a 3.8-litre XK engine from an XK150S being dismantled. This particular engine was last rebuilt by them in 1993 and had only covered some 22,000 miles during that time, having been routinely serviced. Consequently, although there was some wear of the big end bearings (possibly due to oil contamination), otherwise it was always going to be a straightforward rebuild. This is perhaps reflective of many a classic where the engine sees little use, but don’t always expect to be so lucky.