From the restoration of WPK38
1955 was a time when only the most expensive cars paid close attention to wind noise, and by the late sixties whatever remained of the original door seals was in a poor state. Aftermarket seals are made to the wrong dimensions in rubber that is too hard, and the gap between door and body varies along its length anyway.
My solution was to discard them entirely then accurately measure the space they needed to fill — by sticking 'blobs' of Blu-tack at 100mm spacing around the whole door aperture. The door was then closed, re-opened and the Blu-tack (compressed to the gap size) carefully removed and measured.
That gives a precise map of the gap, and shows up the inadequacy of the aftermarket seals at the same time. Four different profiles were then chosen — window frame, A-post face, sill face and B-post — each sized to fill its own gap with a few millimetres of compression, in far more compliant rubber than standard.
After suffering fifteen years of variable levels of wind noise, I finally had a cabin with noise levels almost on par with those of a modern car.
While the doors were apart: drain holes at the lowest point, bottoms and seams waxed, a sound-deadening pad on the skin, and new felt in the window channels, which took the winders from almost impossible to as new.
This passage also appears in the interior chapter.
What else is known
On the coupe and drophead, the original seal along the door and over the screen rail was a single piece; replacements now come in two parts, a black neoprene weather seal with a separate Furflex covering in the trim colour. Coventry Auto Components also note that the hard piping at the top of the door, which wipes the drop glass, can be upgraded by fitting the later XK150 Roadster-style glass seal for a firmer wipe.
The doors originally carried sound-deadening material glued to the inside of the skin, which crumbles with age; a British Car Forum contributor recommends replacing it with modern self-adhesive deadening.
Source: Coventry Auto Components, product notes for parts 6340 and 6480; British Car Forum, “XK 140 doors” (2006).