Some readers may remember the many chapters (threads) I posted regarding a tricky problem with the clutch in my '90 190E-2.3 Sportline. Back in May I posted a thread "Final chapter for 190E clutch saga (I hope)" which you can read at Final chapter for 190E clutch saga (I hope)

Well, up until this morning it was the final chapter, but I am affraid to report there is now an epilogue to the story! I did not use the car over the weekend. I got in it to drive to work this morning and the clutch pedal went to the floor and stayed there. Can you imagine my surprise after replacing the master cylinder back in May and having it behave perfectly since. Pulling the pedal up and pressing it again achieved the same outcome, unlike the intermittent symptom prior to replacing the master cylinder. I lifted the bonnet (sorry, hood) and on initial inspection the fluid reservoir looked full. Closer inspection revealed that the sections of the reservoir for the brakes were full, but the section for the clutch was empty.

I refilled the reservoir and after pumping the pedal by hand for about a minute I began to feel some resistance on the downstroke. Meanwhile, bubbles of air could be seen rising in the reservoir. By continuing this after topping-up the fluid a couple more times, the pedal no longer stayed at the floor. After a couple of minutes I had a usable clutch again (I remebered when replacing the master cylinder how the clutch master cylinder would easily self bleed so long as the slave cylinder was still full). I decided to carry the spare container of fluid in the car and drive it to work. After several minutes of driving, the clutch "feel" was back to normal.

As yet I have not looked for the cause of the fluid loss and am not sure if it has been escaping gradually or if it has been a rapid loss just recently. I suspect the clutch slave cylinder is now at fault given the failure of the master cylinder earlier this year, and the condition of the fluid when I first began investigating the original problem prior to replacing the master cylinder.

All this after being confident everything was fixed with it working perfectly for the past five months. I guess the moral of the story is when replacing worn clutch hydraulics, it is worth replacing everything. When I confirm the cause of the current problem, I will report back. For those who wish to read the whole saga, go to the thread mentioned above. It has links back to the earlier threads describing the initial intermittent symptoms and the gradual diagnosis of the fault.

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107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.

Hello,
Glad to read that you got the car going without tearing into it, I did not have such good fortune today. My W115s' slave cylinder(only 1.5 years old) gave up in dramatic fashion just 300 metres from *my* current indie's shop.
I was actually going there to have the rear bumper mounting rewelded after some dim wit had run into the car last night when it was parked, tearing off the right rear mount. After the repair, I drove off, only to have the pedal drop almost to the floor and no clutch. I had to stall at the first junction, then restart in gear and grind back to the shop in second.
The slave was rusty along the outer edge of the dustcover, I was in a hurry, so we replaced the seal only and reused the rest of the stuff after carefull cleaning.
I think that the *new* part I bought 1.5 years ago probably sat on the shelf for many years as almost ALL the surviving Mercs here are automatics as well AND Malaysians have *modified* many of the older cars to auto, with either Mercedes drivetrain or Nissan 200SX engine/auto trans combos!
Have a good week.

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Nachi11744

It appears that the clutch slave cylinder leaked causing the loss of fluid. Whilst I have not been under the car to confirm this, I have noticed a patch of fluid where the car was parked over the weekend. The fluid loss must have been fairly sudden as the patch of fluid was not there previously. The car drove fine yesterday and this morning and there was no fluid loss under the car at work yesterday or at home last night. I will monitor the situation but it looks like I might be up for a new slave cylinder soon.

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107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.

This is why I have a shop rule.
If the clutch slave or master cylinder is bad, they are both replaced at the same time.

My Direct Experience over 35+ years:
If one has failed, the other (typically) will fail within one year.

.

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1985 300SD
1983 300D
1984 190D
2003 Volvo V70
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This is good logic, probably both made in the same plant with the same batch of materials, exposed to the same fluid and operating conditions. They are effectively Siamese Twins and will die within hours of each other.

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Prost!

Gents, the clinders are dropping in price too!!! After checking many sources I looked to see if someone posted rbld kits they had been keeping after giving up. To my surprise, i saw some new cylinders offered for less than $20.00 us. you could do both and save a tow bill. Last time i asked, the fuel cost after katrina had raised a basic tow another $30. when times are tight, it pays to have these goto sites at the ready. Those plastic cylinders work on ZF trans for Ford. And they have been on their f series and ranger trucks since the 80's. they use an o'ringed line and a pin on pickups. But at first, the NP435 used a brake style fitting. These, as i understand, are similar to the benz steel line and fitting. anyone overtightening this line had a leaker. its not rethreadable after it splits the plastic. hairline cracks after years of use also has been seen at the fitting. its a german design for Ford so it seems likely to be similar plastic