[xk] 140 FHC can't open bonnet, release not working

I struggled for way too long fiddling and adjusting the bonnet release mechanism on my 140. I couldn’t adjust the mechanism such that it would open the latch when pulling the release cable knob.
I found that doing this with the grill removed made it easy to release the latch over and over by hand when I couldn’t get it adjusted properly. I tried almost every configuration of the mechanism I could think of, but no matter how hard I pulled on the knob, the mechanism wouldn’t release.

So I gave up and fitted one end of a small flexible wire to the release mechanism, the other end hangs down below the bumper. It’s easy to pull the wire and the mechanism will now release. I still mostly use it since then.

One day I decided to detach the release cable from the latch to again try to find out what I was doing wrong. Then I found that when pulling on the knob, the internal wire cable would still only move outward about a centimeter or so, and wouldn’t move any further in that direction and therefore would not come out of the outer cable sheath. It seemed as if the cable had failed internally somehow, limiting outward movement of the internal wire bundle to only about one cm. It slid freely in the other direction.

After some fiddling, the only way to get the internal wire cable out, was to cut the internal wire cable off at the knob end, then I could remove it out the outer cable sheath, by pulling on the internal wire from the end formerly attached to the latch.

Then I finally found out why the latch wouldn’t ever open by pulling on the release cable.
One single strand of the internal wire bundle had broken off at the knob end, the broken end of that one wire strand protruded slightly from the wire bundle, jamming itself firmly against the internal surface of the outer cable sheath, preventing the internal cable from moving outward more than about a centimeter.
So, no matter I hard pulled on the knob, the movement of the whole internal wire bundle was firmly limited to about a cm, just inadequate to fully release the latch mechanism, no matter how it was adjusted.
Replacing the cable solved the problem.

That one single strand of the internal wire cable bundle, broken off at the knob end, but still wound tightly up in the wire bundle, would have to be in compression when the knob is pulled and that end of that strand interferes with the inside of the cable sheath. Every other strand would be in tension.

I’m still impressed that the troublesome broken end of one thin single wire strand, when in compression, didn’t just simply bend over and allow the rest of the wire cable to slide relative to the cable sheath. The clearance between outer cable sheath and the internal cable wire bundle must have been just tight enough to prevent that one strand end from bending over and out of the way.

That’s a great story Gary. It’s amazing how many different ways our cars find to cause the exact same problems.

Chet

I’ve met this before with throttle cables. The inner bundle is a very close fit in the sheath, so the wire simply cannot fold over, there’s no room for it to do so. It just hangs up until something, somewhere, breaks, if you pull hard enough!