TheSamba.com :: View topic - Clutch Slave Cylinder Failures

Mon Jun 13, 2016 11:32 am

I'm stuck again with a failed clutch slave cylinder - I seem to get about 8-9 months out of them on average. I'm wondering if anyone else is having issues with these, and/or if there is something I should check for, like maybe a travel limiter on the clutch pedal, or maybe a wrong clutch lever on the transmission or something.

Background:

The 32 year old original gave up in a spectacular fashion the 2nd day I owned it as I was getting ready to drive to the shop and replace it as a part of my PM plan. I wrote this one off to old age and patted myself on the back for already having new master and slave cylinders in a box in the back, ready to go, losing only a few hours doing a quick parking lot diagnosis and waiting for a tow.

The 2nd gave up after offering me the warning sign for a week or so of a slightly lighter feeling clutch pedal (sporadically) just before it became difficult/impossible to shift, and then finally spewing its guts out in traffic (leaving me thankful there's no clutch safety switch and that I got that TDI starter which effortlessly starts it in 1st gear!). I wrote this one off to bad luck.

#3 has been similar to #2 - sometimes when commuting home, I'd think to myself, "Did the pedal just feel a bit light again? Nahhh, I'm just tired and that thing is just a few months old, lightening doesn't strike thrice!" Well, it certainly did..I once again got home thanks to the lack of a safety interlock and an overpowered starter!

While tempting to curse my luck, or the Westfalian Gods; part of me is wondering if there's something amiss here..any insight appreciated!

Mon Jun 13, 2016 11:49 am

The last time mine shit the bed I sent it here for them to sleeve it http://www.rkarpsleeving.com/RK_Sleeving/Home.html i got a rebuild kit from rockauto or NAPA auto and It has been going fine so far. It was a more expensive option than buying a new one but hopefully with a SS sleeve inside the pitting of the cylinder over time will be greatly reduced.
They did a great job with mine and the turnaround time was fast.

Mon Jun 13, 2016 12:21 pm

what failed???? did the rubber bits swell and tear? if so suspect oil contamination but that begs to ask why has not the master failed?

poor quality rebuilds????

where you buy these from?

could there be gross missalignment of cylinder and the pushrod to the clutch arm???? that maybe could cuase them to fail.

weird to say the least. at least it is only the clutch and not your brakes!!!!

good luck

Mon Jun 13, 2016 1:41 pm

mine failed a week after I got my van (march 2016) it was original. I replaced it with van-café fte I think. so far so good. I haven't done the front yet. going for the big-bang when I do the front I'm going to do everything up there (that samba consensus says should be proactively changed).

Mon Jun 13, 2016 7:34 pm

The seals are failing, basically. I didn't dissect the old ones for RCA, as I figured the first failure was to be expected and the second a testament to the so-so quality of a lot of replacement parts these days. Of course, I do plan on taking this one apart now.

The first replacement came from Bus Depot, the second came from Van Cafe. I am pretty sure they were both FTE. I've replaced everything but the hard lines in the brake/clutch system and pressure bled everything pretty thoroughly when I first did the work, and then again a couple months after..fluid is still clear in the brake reservoir.

Well...except the flex line between the chassis and slave cylinder as I remembered when I was ordering up the new slave cylinder, because I couldn't find anyone who had it when I was doing all that work. In hindsight, I should have just had one made at a hose shop; but those arrangements are tricky when you're working on your only mode of transportation. While I figured it was OK since it's not in a high heat or high pressure location (as compared to brake lines at least), I am wondering if it's deteriorating inside and the debris is tearing up the seal. That would explain why my issues are isolated to the slave cylinder and not affecting other parts of the system.

Van Cafe has a new slave and a flex line on the way to me now. Fingers crossed.

Mon Jun 13, 2016 7:51 pm

What fluid are you using?

Mon Jun 13, 2016 8:04 pm

Nothing special, just run of the mill DOT-3 from the parts store..

Mon Jun 13, 2016 8:10 pm

Are you in Portland OR? If so, sourcing your parts from Halsey Automotive would be much easier. They've never let me down.

Tue Jun 14, 2016 5:17 am

Sadly no - I just moved down to SoCal for a new job a few months ago..need to update my profile info I guess!

Tue Jun 14, 2016 3:11 pm

I've had 2 FTE master cylinders fail. Might be worth noting.

Tue Jun 14, 2016 8:11 pm

Did you change it up after the 2nd time?

Wed Jun 15, 2016 7:10 am

A slave cylinder is a pretty simple device. I usually take everything apart to find the root cause, in your case, I would do the same. After the inspection you will find the cause. Maybe the bore is rusted, the rubber is deteriorated, etc.

Disassemble it and find the cause. Flushing the entire system with good fluid and replacing the master cylinder is what I would also do.

Sat Jun 25, 2016 4:05 pm

Well, this is fun. Replacing the slave cylinder didn't do it.

So, I called up VC again and just replaced the master too (FTE as well). It didn't fix the problem either..I re-bled, and bled, and bled..I've actually spent the past two hours doing nothing but bleed the thing with no improvement. Clutch pedal clevis and what not is all in good shape (surprisingly), and the master cylinder is bottoming out so it's getting full travel as was the one I took out, but I can't get it in gear with the engine on. So obviously this isn't a hydraulic issue.

More detail on the time of failure: I had driven a little over an hour to go meet some family for an afternoon. I had to park in a pay lot (I'm down in SoCal right now). As I was leaving the lot, all was normal, except I forgot to take the parking brake off before I left (indicator light is out). I let the clutch out partially, heard the rear drums groan a little and remembered I had the brake on (nothing extreme in any sense...I was in a tight parking lot after all), put it in neutral, popped the brake off and when I went to put it in gear again, it was a little stiff getting it in gear. At the next stop light, it was a little stiffer, and at the third, I determined I would be doing the slave cylinder routine again as this is the exact symptom it did the first two times it gave out, and sent myself an email at work to remember to call VC first thing and called a friend to pick me up for work in the morning (sole transportation, baby! :roll: ).

Any input here is greatly appreciated and maybe a little desperately needed...I'm out of ideas. :cry:

Sat Jun 25, 2016 4:14 pm

RaraBlacksheep wrote: Well, this is fun. Replacing the slave cylinder didn't do it.

So, I called up VC again and just replaced the master too (FTE as well). It didn't fix the problem either..I re-bled, and bled, and bled..I've actually spent the past two hours doing nothing but bleed the thing with no improvement. Clutch pedal clevis and what not is all in good shape (surprisingly), and the master cylinder is bottoming out so it's getting full travel as was the one I took out, but I can't get it in gear with the engine on. So obviously this isn't a hydraulic issue.

More detail on the time of failure: I had driven a little over an hour to go meet some family for an afternoon. I had to park in a pay lot (I'm down in SoCal right now). As I was leaving the lot, all was normal, except I forgot to take the parking brake off before I left (indicator light is out). I let the clutch out partially, heard the rear drums groan a little and remembered I had the brake on (nothing extreme in any sense...I was in a tight parking lot after all), put it in neutral, popped the brake off and when I went to put it in gear again, it was a little stiff getting it in gear. At the next stop light, it was a little stiffer, and at the third, I determined I would be doing the slave cylinder routine again as this is the exact symptom it did the first two times it gave out, and sent myself an email at work to remember to call VC first thing and called a friend to pick me up for work in the morning (sole transportation, baby! :roll: ).

Any input here is greatly appreciated and maybe a little desperately needed...I'm out of ideas. :cry:

maybe the clutch has come apart, failmo, capoot, finished. a broken bit of clutch trapped between the disc and flywheel could cause it to never disengage and cuase the lever arm to not fully move.

see if you can operate the clutch arm with a rope and have some one pull on it, if that dont do it, then pull the motlr and inspect the clutch. or skip the rope trick and pull the motor. youve delat to much time of the slave and master with no smoking gun, and no improvement, time to move on to the clutch itself me thinks sure pulling the motor (or tranny) is no fun, but that maybe what you need to do.

good luck.

PS I have an fte slave in my van, 30 k miles and still good

Sat Jun 25, 2016 6:07 pm

Be sure your radius rod is not missing or misaligned. It's the diagonal support (shown here as part 25A) which helps stiffen the main clutch slave cylinder bracket.

If this is missing or loose/bent, it can allow the main mounting bracket to flex too much and cause problems such as you're experiencing, and can eventually cause the main mounting bracket to break.

It would be worth your time to have a helper pump the clutch while you observe the slave cylinder, looking for signs of flexing.

Sat Jun 25, 2016 6:15 pm

I am unclear if you have been able to confirm that he slave is moving the arm on the transmission.(part 20) If it's moving well then things seem to point to a clutch issue.

I did have an FTE fail in a couple years and have been running one from O'Reillys. Here is my experience http://www.thesamba.com/vw/forum/viewtopic.php?t=503226

Sun Jun 26, 2016 4:31 am

Check the release lever and make sure it isn't loose/worn. If it moves a bit because the three alignment splines are worn. Will ride poor clutch release.
It's #20 in the diagram posted by Jeffrey.

Sun Jun 26, 2016 4:56 pm

The bracket mentioned above was in place and no signs of it moving or being bent since before the problem. No slop in the lever, that I could detect at least. I attempted to tie it down but there's a lot of force there, nothing I had on hand could keep it in place.

The slave is moving - but it's acting like it wasn't moving enough. However with all new hydraulics and no signs of something being awry outside of the bellhousing, the issue is inside the bellhousing somewhere. I'm going to see if I can find a pressure bleeder to borrow just to be 100% sure before I send it off on a tow truck, but that's about as far as I can take it this time around.

Thanks for everyone's input..