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1979 240D 4spd
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4 Posts
Discussion Starter #1
Hey Team!
I am having a weird problem. My 240D (4 sp manual) was doing fine until 2 days ago. After I started it I let in warm up a few minutes and went to drive off. I could not get it from neutral into gear when the clutch pedal was depressed.

I did a little research and it seems like it might be the piston (too short/worn out) in the slave cylinder on the side of the tranny. I checked the brake fluid and it is full (no leaks, I think).

It seemed strange because it happened without warning. If it happened slowly that would be consistent with a leak, but the suddenness of malfunction made me wonder if something fell off, but the clutch system is hydraulic not linkage. I am in Edmonton, Canada, and it was maybe -15C the day it broke.
The action on the clutch pedal feels fine.
I can put it into gear when the car is off.

Any thoughts?
I am going to tear off the slave cylinder and see what I can see. Any instructions on that operation?

Curtis
 

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2001 Volvo V40
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2,954 Posts
The slave cylinder often leaks into the bell housing, the leak is not always big to start with, but big enough to fail to declutch.

Inspecting it is easy, it is two bolts. You can leave the hydraulic line connected.



if the inside is full of fluid, it is leaky. Watch out for the hydraulic fluid, it is bad for your health when it comes into contact with your skin.

And if you do have to replace the slave cylinder, you might want to consider changing the master cylinder too, as they tend to fail soon after each other.
 

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Premium Member
99 SLK230 Kompressor, 5 Speed Manual
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1,117 Posts
This is most likely a clutch hydraulic problem, but the slave cylinder is only one possibility of its cause.

Start by making sure that the fluid level in the master cylinder reservoir is above the clutch fluid nipple on the outer portion of the reservoir. If it is not, fill it and pump the clutch. Even if it were to pump up a little, you have a leak somewhere in the system. Lift up the drivers side floor mat and check for fluid. If there is fluid under there, rebuild or replace the lcutch master cylinder. If there is no sign of leakage at the clutch master cylinder, check the slave cylinder as the previous poster suggested. I check the clutch master cylinder first because it's easier.

If both of these cylinders look good, don't overlook the lines. The soft line from the reservoir to the clutch master cylinder just slips on and it is old enough to be rotted.

Hope this helps.
 

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money pits of various forms
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5,885 Posts
Hoses could be leaky as well.
 

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1980 240d 4 speed manual a.k.a. Big Red 1981 240d (Black Mamba)
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32 Posts
same problem

what did you do to fix it? I'm having the exact same issue.
 

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1983 240D 3.0T
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242 Posts
Watch out for the hydraulic fluid, it is bad for your health when it comes into contact with your skin.
Hopefully not too bad, I got drenched in the stuff :(.

I've had a master cylinder fail on me without warning and without losing any fluid.
 

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5 Speed "85" Euro TD , 5 speed "85" Euro 240D, "79" 5 spd 240D, 5 spd "94" Dodge/Cummins PU
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664 Posts
Before you tear anything apart pull down the carpet up between the pedals and feel for the hard line coming from the clutch master cylinder. It will be wet with brake fluid if its leaking and causing your problem. Just to clarify, you did make sure BOTH chambers of the M/S are full, OK, just checking.
 

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5 Speed "85" Euro TD , 5 speed "85" Euro 240D, "79" 5 spd 240D, 5 spd "94" Dodge/Cummins PU
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664 Posts
Soo, did you figure out your clutch problem?
 

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1980 240d 4 speed manual a.k.a. Big Red 1981 240d (Black Mamba)
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32 Posts
I did, replaced the master cylinder, and reverse bled the slave and master from the front passenger brake line. and it's running. wasn't that difficult. just took some time because I had to figure out what I was doing without a manual.
 
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