Clutch cable life span?

My VS has 7200 miles on it (including 1K with a new Kennedy 1700# clutch). I JUST made it home today to find only a few good strands left at the rear adjuster.
I've already Email-ordered 2 cables from Kirk, but upon searching the forums, I find that this is a fairly common problem. Just wondering HOW common.
Thanks, Ernie

Lost mine at about 3000 miles. Found Bowden tube not well aligned and rubbing. Glad it happened. With re-adjustments and grease, I cut pedal effort about in half!

My CMCs are good for about 10 to 15,000 miles. However, the tubes were not as carefully prepared as Kirk's. I say always keep an extra cable under the bonnet. It does not talk long to replace one.

What section of the clutch cable typically fails? I have 28,000 miles on mine and it looks fine. I have also heard it is good to carry a spare wing nut on your spare cable.

Dale:

Different Clutch Cable Failures:

If the Bowden tube is mis-adjusted, it can cause a couple of different premature failure scenarios to happen:

1. If the Bowden tube has too much or too little curve to it (or hasn't been greased properly), it can cause the cable to wear where it rubs against the inside of the tube. This typically takes a LONG time to fail (40,000 miles plus). You'll also notice that the clutch chatters when engaging, so when that starts to happen people usually would take their car in for clutch service and the tech finds the problem, adjusts the tube and everything is OK, before the cable wears out.

2. Second problem is where the cable exits the Bowden tube. If you look at it from the side you'll see why; if the angle of the exiting cable is different than that of the tube collar, it causes the cable to chafe and eventually wear through. If the angle is acute, this can happen in 10K miles or so, depending on stop and go driving. An astute mechanic will spot this early and adjust the tube such that the cable comes straight out of the collar and doesn't chafe (and he probably re-greases the cable at the same time).

The only other failure mechanism I've seen, is the little loop wearing off of the forward end of the cable where it hooks over the "tooth" of the clutch pedal arm, and, very rarely, the clutch pedal arm "hook" simply wears off or breaks, but that is not a cable failure.

MUCH more common on Speedster Replicas, is a two-piece clutch cable, where the longer sedan cable is simply cut, overlapped and spliced together with a couple of 1/8" cable clamps to get to the right length. I've finally given up on this approach, as it tends to slip over time (at least for me) and never seemed to be reliable. Instead, I take a sedan cable to a sail boat rigger and have them cut it to the length I want and swage a new, metric (M6, I think) threaded end onto the back. That size end is very popular with the European sailboat crowd (Bennetos, etc.) so they're relatively easy to find. Usually costs me about $15 to have it done (plus the cost of the sedan cable).

BTW: Back in the "Old Days", VW clutch cables would easily last as long as a clutch, and I've seen both go over 100,000 miles before replacement, depending on the driver. Average was somewhere between 50K and 75K miles for both, and the cable was always changed when a new clutch/throw-out bearing was installed.

Well....
I went out and took a picture of the lil' bugger. However, the photo ain't loadinding up (on SOC) too well tonight. It does appear to me that the cable strand breakage is located exactly where the cable meets the cable adjustment end fitting that engages the clutch arm.
I'll try to post the picture again tomorrow, but for now I'm just waiting for the mail man to bring me the fix (new cables) from VS.

Here ya go!

Well-sir....you can always learn from someone else's problems...

That picture looks, when everything is at rest, like the cable angle and the adjuster swedged end are in line enough that shearing isn't an issue. Besides - there isn't anything there to shear with, right?

The only thing I can think of is that the ball end of the adjuster wing nut is rusted and isn't moving enough in the socket of the throw-out-bearing arm, causing the cable to fracture where it enters into the crimp lug when the clutch pedal is depressed. As the pedal is depressed, the clutch arm on the side of the tranny moves forward in an arc, and the adjuster wingnut acts like a ball and socket connection, allowing the ball (nut) to move, which allows the adjuster stud to move around slightly, thereby keeping the cable and adjuster end straight with each other (or enough to keep the cable from shearing).

The adjuster wingnut is big (1-1/4 inch across the finger wings) and has a ball shape on the end toward the cable that fits into the "socket" of the throw-out arm. There are also some little slots in the socket and protrusions on the nut to keep it from slipping out of adjustment. If the nut ball is frozen to the arm socket or rusted enough to keep it from moving enough, then it can cause the cable to break as you see it. Our cars typically sit a lot, so the potential for these two rusting together is pretty high.

How does it break the cable? As the pedal is depressed and the tranny arm comes forward in an arc, if the ball is rusted in place it will cause the adjuster stud to angle abruptly down, more than the angle that the cable wants. As it angles down, it over-stresses the outer strands of the cable (at the top and bottom, first) and eventually fractures them from the outside inward.

How do you prevent this?? Easy. When you install that new cable, use some sandpaper to polish the socket in the throw-out arm, and also polish the ball end of the adjuster nut (don't get too wild polishing the little ridges on the ball of the nut - they're needed to keep it in adjustment. Just make them shiney).

When you put everything together, coat both the socket and ball with white lithium grease to keep it from seizing up down the road. If you really want to insure that your eventual adjustment doesn't change, you can install a nylok metric locknut on top of the wingnut and lock the two together (always a good thing).

BTW: VW used to have a "special tool" used to leverage the tranny arm forward so that the mechanic could put grease on the cable ball and socket at regular service intervals (15-20K miles or something like that) so that the cables would last. I just use a pair of BIG waterpump pliers. Always a good thing to do once a year, as you are doing your "Spring Maintanence".

Of course, when we were driving our Beetles all the time, that much use caused those parts to be polished all the time and they never seized up. Remember: "To Sit is to Rot!"

Got the cables from VS this AM (Good service or what?). Next I found that there is an access panel on the pasenger side of the tunnel. So far, so good. Now if can only get the gal-durn cable out of tube.
As for the winged adjuster nut. Gordon, the thing is shiny like new. It was not greased, however. (It will be when I get this thing done) I'm thinkin' that my cable was somehow defective or unable to rock in the clutch arm socket for lack of grease.

OK! Test drive results= It's All Good!
I did lose my "bodin tube virginity" on this deal: had to yank it to get the cable all the way to the clutch release arm. Live and learn!
The SOC site was here for me thru-out this mechanical adventure. Everytime I found a road-block, I just came back here to do and to find the info I needed.
Thanks Again, Ernie