Clutch Adjustment (Discussion)

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Why does the clutch need adjusting?

As the clutch linings wear, the clearance (free play) decreases. If it is left this way it will eventually get to where it slips and burns the linings, resulting in difficult shifting and engagement.

See our Clutch Adjustment Procedure. We found the following verbiage on the Internet -

To adjust the clutch you'll have to find the wing nut on the rear end of the cable. Itís located on the upper right side of the transmission as your looking at it from the left wheel well. You can either jack the rear up, place jack stands under it, and work from the bottom which is the easiest way. Or, the other way is to remove the left rear wheel and work from there.

(Itís a weird fit, you might have to try several positions to get at it.)

Grab the cable with the pliers to keep it from twisting and loosen the wing nut a little. Then check and see how much free play you have at the pedal. Press the pedal till you feel working resistance. You want about 3/8-3/4in. of free play.

When you get the correct free play make sure that the wing nut's face is resting in the depression in the clutch lever arm.

Rob reports - My cable end (the threaded part) has "flats" on the forward end, so you can put a small crescent wrench on it to hold it still.

Dave wrote - Years ago when I replaced the clutch in my '65 Beetle, I learned a neat trick that makes adjustment of the clutch way easier (you probably know all about this and are laughing up your sleeve at me). I have someone depress the clutch while Iím laying under the car, then I slip a 3-inch socket extension between the clutch lever and the firewall. Then when the clutch is released the cable goes slack and turning the wing nut is a snap! This after much frustration trying to turn the nut as it was pulled tight against the lever. Havenít had occasion to do this on ourí73 Bug, as the clutch was replaced just before we bought the car and the clutch hasnít yet needed to be adjusted. I stay on my sonís case about riding the clutch, just like my Dad did with me! (All you have to do is replace it once and you become a believer!)

Rob responded - Yes, I had heard about this trick -- it certainly makes the nut easy to turn, but it also makes it impossible to check how far it's been adjusted until the wedge is removed. No problem if you have an assistant standing by, but I usually have to do it by myself, so prefer to leave the cable under tension. Iíve found that with a squirt of WD40 on the thread and wingnut it turns OK, even under tension. It would be handy to have a longer arm though to reach that area on the car. I jack it up and take a wheel off -- MUCH easier...

Dave wrote - I went out a few minutes ago and checked the clutch pedal freeplay on our Bug (I've never messed with it since we bought the car. The freeplay is about 1-1/2"; max per spec is 3/4". Do you think this might be enough to be causing the intermittent problem we're experiencing with shifting into 2nd?

Rob responded - Big sigh of relief when I read this. This is certainly the most probably cause. The clutch plate would still be grabbing slightly with this amount of freeplay, so the grindy gear changes are very likely.

Easy to fix -- just turn the wing nut on the clutch end of the cable a few turns (clockwise when looking towards the front of the car). It has a sort of castellation under it (like a bump-and-dip) to prevent unintended loosening, so it can be a little tough to turn it each half turn as it tries to lift over the bump and settle into the next dip. After two-three half turns, check the free play at the pedal again. It's much easier to reach this wing nut if the left rear wheel is removed, and you sit where the wheel was to reach in from the side. A squirt of koil or WD40 will help it turn if it is too stiff.

I keep my freeplay to between 1/4 and 1/2 inch, which is enough to ensure the clutch fully engages when you take you foot off, but provides plenty of clutch cable travel for a good clutch release.

The clutch has to be checked/tightened every 10,000 miles or so (say every three oil changes) because the cable 'loosens' with normal wear on the clutch. If your son rode the clutch at all, or liked holding the car on hills with the clutch instead of the hand-brake, it WILL have worn faster and produced a loose pedal.

Also check that the bowden tube which takes the cable into the body to make sure it has the required bend in the center. The amount of bend is adjusted by slipping C shaped washers under the rear end (I cut a section out of a normal washer so it will slip over the cable after loosening it a lot). I forget the actual amount of bend about an inch I think. The bend is essential to allow for the gearbox to rotate a little on it's mounts as the engine torques it, without pulling on the clutch cable. Without it, every gearchange would be Kangaroo hops.

Dave wrote about a shifting problem - It doesn't happen every time, but about one in every four shifts I cannot get it to go into second gear. It grinds and grinds but won't go.

Rob responded - I have driven mine with a broken clutch cable on several occasions. Into neutral and coast to a stop at the lights. Engine off. Shift to 1st. Lights change. Engage starter and lurch into motion. Double clutch to change gears -- the synchro helps it click into gear when you put gentle pressure on the stick and rev the engine in neutral to match the speed. Changing down is a little harder -- have to rev PAST the change point and let the revs die whilst nudging it into gear at the right moment. Great fun, and concentration needed. What a forgiving car.

Dave asked Rob about his slipping clutch -- Rob wrote in response - First adjust it so the pedal works in the first half of travel - not down near the floor.

Hopefully that will help. Other possibilities... the clutch plate may be worn out even though there appears to be plenty of "meat" on the friction plate - the diaphragm clutches does not have quite as much travel as the older style coil-spring VW clutch plates, and so looses some of it's pressure as the friction plate wears. Also -- did you notice is the flywheel clutch surface was mirror shiny or still slightly "machined" in appearance - a shiny surface has less grip - the flywheel surface may need machining (commercial shops rarely mention this part when changing a clutch - they just rely on the replacement pressure plate (with IT'S machined surface) to give enough grip.

Any chance you have oil contamination of the friction plate? Could your engine removal have moved something? Two common leak points are the main seal behind the flywheel, and the gearbox main seal - these are either side of the clutch of course, so leaks from either can get on the friction plate.

 

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