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Mon Dec 18, 2017 4:48 pm

Hi there,
We bought this 1965 beetle a couple of years ago. The previous owner installed a hydraulic clutch, which I have no experience with.

I thought I sensed the beginnings of a slight shutter sometimes when releasing the clutch. The pedal free play seemed to have increased slightly. I measured it at about 1.5". The fluid level is good.

So, I guess I need to remove some of the freeplay, but I'm not sure if it should be done at the clutch lever arm like a normal adjustment (adjustment nuts in the upper right hand corner of pic), or if I should move the whole cylinder toward the front of the car and leave it alone at the clutch arm, by adjusting the nuts in the lower left hand corner of the picture:

Any help is appreciated! I really wish the previous owner had kept the stock setup!

Mon Dec 18, 2017 5:17 pm

Paul,

You should use another nut to sandwich the cylinder to the bracket on the transmission. This way, the slave cylinder won't move either way, so you can adjust the free play.

Mon Dec 18, 2017 6:31 pm

And bleed the clutch hydraulics, couldn't hurt.

I'm not a huge fan of installing a hydraulic clutch system on a beetle, not necessary in non-racing situations, and sometimes not even then.

Mon Dec 18, 2017 11:57 pm

I'm curious about how the clutch pedal is arranged, would you post some photos?

Thank you

Tue Dec 19, 2017 6:01 am

Terry Gaudet wrote: Paul,

You should use another nut to sandwich the cylinder to the bracket on the transmission. This way, the slave cylinder won't move either way, so you can adjust the free play.
I don't think so, the clutch slave needs to be able to pivot on the ball end of the nut on both ends. It has to be in a strait line between the arm and the base mount as the arm swings.

To the original poster, I don't see why it makes any difference which end you chose to adjust at, so long as neither end is run down to the point of restricting the motion of the slave cylinder as the clutch is depressed. I plan to run a hydraulic clutch on my Berry Mini-T and that is what my transaxle looks like, so thanks for the picture of the slave installed.

Tue Dec 19, 2017 10:03 am

Guys, thanks for that input! I guess I will adjust the nuts closest to the front of the vehicle because they appear to have more threads. The only lingering question is:

Does the pedal freeplay need to remain at the stock 3/4" when the whole setup has been overhauled anyway? Maybe a good amount of freeplay on my system is different from stock...

To Herbie 1200:
These are my pedals. They look stock. I haven't actually been inside of it myself, but the master cylinder is located in the tunnel, right by the pedal cluster. Accessed through a door on the passenger side of the tunnel.

I don't want to peel back the carpeting to get a picture of the master cylinder today.

Tue Dec 19, 2017 10:24 am

Shuddering when releasing the clutch is normally caused by flaws in the disc to flywheel and pressure plate engagement: things such as contaminated friction surfaces, burned or warped flywheel, uneven pressure plate engagement, or rust. Second to that would be shuddering caused by worn or torn transaxle mounts. It's not very likely your problem is due to excessive pedal free play.

Have you noticed any pattern to when it shudders, such as after the car hasn't been driven for a while or the humidity is higher? Is there any evidence of an oil leak from the trans/engine mating area?

Tue Dec 19, 2017 11:23 am

mukluk,
For some reason I thought I read that shuddering could be caused by a pedal freeplay which is badly out of adjustment. But now I can't find it. I must have dreamed it. I mostly noticed the shudder going from 3rd to 4th at around 50mph. Mounts seem to be likely now that you mention it. The shudder was very subtle compared to what I feel on my bus, which does have contaminated friction surfaces due to a failing main seal.

But the shudder was the reason I measured the freeplay and I was alarmed at nearly 2 inches.

I consulted the last mechanic who worked on it. He said the pedal freeplay should still be at stock spec because the throw is the same on the hydraulic conversion as the stock setup. He said the length of the piston makes it work that way.

I went ahead and adjusted the lower 2 nuts from which the slave cylinder is mounted. The upper 2 nuts on the clutch arm had no remaining threads, as far as I could tell. So, I supposed it was designed to be adjusted from the lower 2 nuts.

The symptom seems to have gone away. The action feels better on releasing the clutch.

Since I was deeper in there, I decided to get some better pictures, for anyone who wants to see.

Thanks again for the input!!

Wed Dec 20, 2017 1:15 am

Thank you for the photos.

Just a consideration: when clutching the clutch arm rotates so the point of application of the force varies. During the course the piston end is not always perfectly orthogonal to the clutch arm.

For this reason in the stock arrangement the butterfly nut has a spherical shape on its base, to accomodate the movement during clutch operating.

A good improvement to your configuration should be to rework the base of the nut making it ligthly spherical.

Wed Dec 20, 2017 9:30 am

..and greasing both the end nut and the rod at the other end. AS posted, there are shear loads on both as the unit actuates.

Wed Dec 20, 2017 10:23 am

herbie1200 wrote: A good improvement to your configuration should be to rework the base of the nut making it ligthly spherical.

Or put it on the other way.