Two Bolt types for Spare Wheel Clamp
There are two types of bolts to clamp down a wheel in the boot of the XK: one suited for disc wheels and one for wire wheels. The bolt for the disc wheel is coded BD6420 and has dimensions ¾ x 6¾ inch or 19 x 171mm (and not 11/16 x 8 9/16 inch or 17½ x 217½ mm as mentioned by Porter). The bolt for the wire wheel is coded BD9583 and has dimensions ¾ x 8¾ inch or 19 x 222 mm.
The disc wheel version is also used on all saloons of that era and they seem to be better available than those for the wire wheel version. It is possible to modify the disc wheel version to the (longer) one suited for the wire wheel. A lathe, however, is required for this operation.
Modification of Disc wheel Bolt BD6420 to Wire Wheel Bolt BD9583
It is possible to modify the spare wheel bolt of the disc wheel to one for the wire wheel. Follow these steps:
- Remove the black knob by driving out the pin.
- Cut off the 2.3” long Ø ½“ rod from the threaded part of BD6420.
- Turn a new longer rod on a lathe according the below given dimensions
- Connect the new part to the threaded part of BD6420.
- Replace the black knob