My dads 200E was struggling to select gears the other day and then started smoking a lot from the engine bay. The car had to be towed home eventually. Does anyone know what could be the cause of this problem? Could it be failure of the pressure plate causing the clutch plate to burn out? Does this car have a hydraulic clutch mechanism? Any help would be much appreciated.
Clutch Problem on 93 200E 124 series
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Yes it does have a hydraulic clutch, the chances are that the clutch plate has burnt out hence the smoke, so it will need a new clutch, hopefully the flywheel will be OK, but does not sound too good
Ian B Walker
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After you have fitted a new clutch you will need to bleed the system. Easiest way to bleed the clutch is to take some rubber hose and fit it to the bleed nipple of the front right hand brake caliper. the other end fit to the clutch slave cylinder. Open both bleed nipples and pump the foot brake slowly.
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No the hydraulic part is only for the operation of the pedal, the chances are that the pressure plate worn out
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Brilliant, I could not think of why a clutch just fails, I bet that you are spot on with that
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I think that you may be right Ultymate. My dad did say that it struggled to select gears initially then he drove for a bit and then there was a lot of smoke. Came through into the cabin. So he stopped for a bit and waited for the smoke to go away. He then drove it to a safe place and decided to get the car towed home. Is the slave cylinder near the exhaust pipes? I just assumed the pressure plate failed and a caused the clutch plate to burn out causing the smoke? Is there any place where I can get engine diagrams and layouts of this car?
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Yes it will affect the clutch, with no hydraulic the clutch would not work.
From what you say, there were smoke from the engine bay, it should be the rubber hose which connects from the clutch pump to the pedal would have leaked and oil would have splashed on to the hot exhaust pipe, this could be the cause of the smoke. So check this flexible hose for any crack or damage.
Also check the brake fluid container and see for the level.
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Personally I'd go with Malcom on the clutch plate (was there a touch of sarcasm?). I've seen them disintigrate before, although only when people practice boy racer type starts. It's surprising how much smoke suddenly appears. It tends to smell similar to the smell of hot/binding brake pads.
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CLutch help Pleeze
We had the entire clutch changed with a new kit a short while after this was originally posted. My dad does not do much mileage in this car and it sits mostly in the garage. The car did less than 5000 km over a few months. He took it out one day for a short drive and a few km from home he said there was a loud crack sort of noise then the same story all over again. Hell of a lot of smoke and clutch slipping. So now this clutch is cooked again. This is the third clutch that has gone in this fashion in this car. I am really at my wits end here. Could it be that due to the car sitting for long periods of time because of a bad seal on the gearbox bellhousing and oil could be getting into the clutch plate and fouling it? Or could it be just pressure plate failure? After the last clutch was installed I did notice a bit of a shudder when the clutch was released. Could this be a damaged flywheel burning the clutch? I did speak to the guy who changed the clutch the last time and he said the flywheel did not need machining. My dad is 83 and has his licence since he was 20 so its definately not poor driving. Could this whole thing just be due to poor fitment and adjustment of the clutch. Please guys and ideas or even a theory would help. This is now going to be the fifth clutch im replacing for my dad and its hurting my wallet now. :cry::cry:
We had the entire clutch changed with a new kit a short while after this was originally posted. My dad does not do much mileage in this car and it sits mostly in the garage. The car did less than 5000 km over a few months. He took it out one day for a short drive and a few km from home he said there was a loud crack sort of noise then the same story all over again. Hell of a lot of smoke and clutch slipping. So now this clutch is cooked again. This is the third clutch that has gone in this fashion in this car. I am really at my wits end here. Could it be that due to the car sitting for long periods of time because of a bad seal on the gearbox bellhousing and oil could be getting into the clutch plate and fouling it? Or could it be just pressure plate failure? After the last clutch was installed I did notice a bit of a shudder when the clutch was released. Could this be a damaged flywheel burning the clutch? I did speak to the guy who changed the clutch the last time and he said the flywheel did not need machining. My dad is 83 and has his licence since he was 20 so its definately not poor driving. Could this whole thing just be due to poor fitment and adjustment of the clutch. Please guys and ideas or even a theory would help. This is now going to be the fifth clutch im replacing for my dad and its hurting my wallet now. :cry::cry:
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Some theories, and a rudimentary description of the parts and their role.
The clutch mechanism at the tranny end is self adjusting. The pedal end may require adjustment if the master cylinder is replaced, but I think this is only on early models, one of the others may be able to clarify this (my 190 is devoid but Haynes says it has).
Shudder on release is often due to a poor rear engine/transmission mount, all 3 may be suspects.
You are not going to find out what has actually failed until its taken apart.
There is a method of checking for clutch wear, its shown in the Haynes book, a collapsed lining will show up as excess wear.
Were the hydraulics attended to in anyway when the clutch was changed?
Oil would make it slip and this has an effect on the way the pedal feels at take off, typically you don't need to be careful and it wont stall. Smoke (oily smelling) would be produced if you floored it and allowed the engine to race whilst driving, perhaps not your dads style.There would be evidence of oil leaking/dripping at the bottom of the bell housing.
Worn linings will leave the fixing rivets against the pressure plate or flywheel and the clutch will slip making smoke that stinks, 'tis 'orible.
A collapsed pressure plate spring will cause severe slip (if not completely loose drive) and might result in lots of lining smoke. From your description of a bang it may be here that the fault has manifested itself.
The linings on the spinner may have disintegrated with similar effect as a fail in the pressure plate, also a possible source of the bang.
When being driven that's all there is, the release mechanism is supposedly out of contact and doing nothing, it consists of a lever with a release bearing to push onto the pressure plate cover at the inner end and a receptacle for the clutch slave cylinder to push on at the other end with a pivot against the bell housing in its middle, other than release bearing collapsing (howling/grunting with pedal pressed) or the pivot seizing or breaking there is not much to go wrong with it, if its the cause of the bang it would be when the pedal was pressed. I suspect that anything amiss here would make the pedal feel wrong.
Bad hydraulics, this may hold a little pressure on the release bearing causing a slip risk and increased wear with the eventual longer term result being slip and smoke.
The master cylinder is mounted inside the car behind the pedal. It is fed with fluid from the brake master cylinder reservoir rear compartment, check this for being low, if its down to the feed tapping (lower LHS of tank) the clutch hydraulics have lost fluid.
The slave is mounted on the bell housing, I cant think of any reasons for it to jam and cause pressure to be held on the release mech other than 1, rust in the slave bore not allowing the lever to return and 2, the master cylinder not always fully returning to the top and not allowing fluid to be able to return to the reservoir, it is here on the MC/pedal that there may be an adjustment. A burst hose would cause the pedal to be ineffective and sink to the floor without resistance when pressed, the clutch would not part and gear selection would be impossible. The lost fluid might fall/spray onto the hot exhaust as it is in about the right place.
I think the car has a normal solid flywheel and if its face is good it wont need skimming, it is not very likely as a total clutch failure candidate, some diesels have a dual mass flywheel which can be troublesome, rattling and clonking at tickover/low speed along with clutch judder, I don't think any petrols have this costly feature.
How does the pedal feel, down to the floor, almost normal or something else?
Its 5 years since your previous post what's happened to the car in those 5 years?
The clutch mechanism at the tranny end is self adjusting. The pedal end may require adjustment if the master cylinder is replaced, but I think this is only on early models, one of the others may be able to clarify this (my 190 is devoid but Haynes says it has).
Shudder on release is often due to a poor rear engine/transmission mount, all 3 may be suspects.
You are not going to find out what has actually failed until its taken apart.
There is a method of checking for clutch wear, its shown in the Haynes book, a collapsed lining will show up as excess wear.
Were the hydraulics attended to in anyway when the clutch was changed?
Oil would make it slip and this has an effect on the way the pedal feels at take off, typically you don't need to be careful and it wont stall. Smoke (oily smelling) would be produced if you floored it and allowed the engine to race whilst driving, perhaps not your dads style.There would be evidence of oil leaking/dripping at the bottom of the bell housing.
Worn linings will leave the fixing rivets against the pressure plate or flywheel and the clutch will slip making smoke that stinks, 'tis 'orible.
A collapsed pressure plate spring will cause severe slip (if not completely loose drive) and might result in lots of lining smoke. From your description of a bang it may be here that the fault has manifested itself.
The linings on the spinner may have disintegrated with similar effect as a fail in the pressure plate, also a possible source of the bang.
When being driven that's all there is, the release mechanism is supposedly out of contact and doing nothing, it consists of a lever with a release bearing to push onto the pressure plate cover at the inner end and a receptacle for the clutch slave cylinder to push on at the other end with a pivot against the bell housing in its middle, other than release bearing collapsing (howling/grunting with pedal pressed) or the pivot seizing or breaking there is not much to go wrong with it, if its the cause of the bang it would be when the pedal was pressed. I suspect that anything amiss here would make the pedal feel wrong.
Bad hydraulics, this may hold a little pressure on the release bearing causing a slip risk and increased wear with the eventual longer term result being slip and smoke.
The master cylinder is mounted inside the car behind the pedal. It is fed with fluid from the brake master cylinder reservoir rear compartment, check this for being low, if its down to the feed tapping (lower LHS of tank) the clutch hydraulics have lost fluid.
The slave is mounted on the bell housing, I cant think of any reasons for it to jam and cause pressure to be held on the release mech other than 1, rust in the slave bore not allowing the lever to return and 2, the master cylinder not always fully returning to the top and not allowing fluid to be able to return to the reservoir, it is here on the MC/pedal that there may be an adjustment. A burst hose would cause the pedal to be ineffective and sink to the floor without resistance when pressed, the clutch would not part and gear selection would be impossible. The lost fluid might fall/spray onto the hot exhaust as it is in about the right place.
I think the car has a normal solid flywheel and if its face is good it wont need skimming, it is not very likely as a total clutch failure candidate, some diesels have a dual mass flywheel which can be troublesome, rattling and clonking at tickover/low speed along with clutch judder, I don't think any petrols have this costly feature.
How does the pedal feel, down to the floor, almost normal or something else?
Its 5 years since your previous post what's happened to the car in those 5 years?
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MechPhil
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My first guess when something like this keeps occurring is always sticky hydraulics. If the brake fluid used to actuate the clutch is dirty, or not of the correct (DOT 4) standard, it may cause the slave cylinder to "stick" by holding hydraulic pressure.
The sudden smoke is a little puzzling though. Yes, a burning clutch plate does smoke, but it takes rather a bit of slipping for it to start smoking... More likely it's a case of oil contamination from either the rear crank seal (not too likely as oil from here runs down the back of the flywheel) or a gearbox input shaft seal (mosre likely).
The release bearing may be sticking (or for some reason not be able to mve all the way back) on the spigot shaft (the "pipe" over the base of the input shaft) it slides on, holding pressure on the pressure plate fingers. When the clutch assembly is still new, the pressure plate only presses down a few millimetres from it's fully disengaged (i.e. clutch pressed in) position in order to clamp the clutch plate. As the friction faces wear, the pressure plate needs to move further in order to clamp down, and if the release bearing gets stuck halfway down the spigot, the fingers cannot travel back far enough to allow the pressure plate to clamp down fully.
You don't say wether you fitted MB clutch kits or an aftermarket brand. I cannot over emphasise the importance of using genuine parts! In the end they do save you money by lasting longer than the opposition.
Last, but not least: make sure the dowells in the back of the engine where the gearbox connects to it, are all in position. (The dowells may also be in the gearbox and fit into holes in the back of the engine) These dowells are important to ensure that the gearbox lines up perfectly with the engine. The bolts alone cannot achieve this, as the holes are invariably a fair bit larger than the shaft of the bolts. A very small misalignment can be catastrophic to the clutch!
The sudden smoke is a little puzzling though. Yes, a burning clutch plate does smoke, but it takes rather a bit of slipping for it to start smoking... More likely it's a case of oil contamination from either the rear crank seal (not too likely as oil from here runs down the back of the flywheel) or a gearbox input shaft seal (mosre likely).
The release bearing may be sticking (or for some reason not be able to mve all the way back) on the spigot shaft (the "pipe" over the base of the input shaft) it slides on, holding pressure on the pressure plate fingers. When the clutch assembly is still new, the pressure plate only presses down a few millimetres from it's fully disengaged (i.e. clutch pressed in) position in order to clamp the clutch plate. As the friction faces wear, the pressure plate needs to move further in order to clamp down, and if the release bearing gets stuck halfway down the spigot, the fingers cannot travel back far enough to allow the pressure plate to clamp down fully.
You don't say wether you fitted MB clutch kits or an aftermarket brand. I cannot over emphasise the importance of using genuine parts! In the end they do save you money by lasting longer than the opposition.
Last, but not least: make sure the dowells in the back of the engine where the gearbox connects to it, are all in position. (The dowells may also be in the gearbox and fit into holes in the back of the engine) These dowells are important to ensure that the gearbox lines up perfectly with the engine. The bolts alone cannot achieve this, as the holes are invariably a fair bit larger than the shaft of the bolts. A very small misalignment can be catastrophic to the clutch!
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Another thing: check the small breather hole in the brake fluid filler cap. If this hole gets clogged, pressure may build up in the reservoir and cause "sticky" hydraulics. It's rare, but I have had a a car do that on me once!
Phil
PS. I understand your dad has a lot of driving experience, but older people often don't hear the motor rev up as the clutch starts slipping. My grandfather raced motorbikes for twenty years and loved cars, but in the end we had to get him an automatic Honda, because his senses had become too dull (never the mind though) to use the clutch... Just a thought, I don't intend to offend...
Phil
PS. I understand your dad has a lot of driving experience, but older people often don't hear the motor rev up as the clutch starts slipping. My grandfather raced motorbikes for twenty years and loved cars, but in the end we had to get him an automatic Honda, because his senses had become too dull (never the mind though) to use the clutch... Just a thought, I don't intend to offend...
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Thanks a lot for the replies guys. I really appreciate it. I had not realised that I posted this 5 years ago. It was the first time the clutch burnt out and I posted the original out of desperation as nobody locally could help me. The original clutch was replaced with a complete sachs kit. This worked for for a while then the same thing happened again. Clutch completely burnt out. The mechanic who looked at the car said the slave cylinder had failed causing the clutch failure. He repaired it ...im not sure how and put in another clutch. This clutch lasted a very short time also failing and burning out. We then replaced this again with a Valeo KIT this is the final one which lasted around 5000km then it failed as I have described today. The car has actually been parked for about nine months now because I am tired of replacing clutches and its cost me a lot. MechPhil the smoke was due to the fact that my dad continued driving burning out the clutch plate completely. I think you guys are onto something with the faulty hydraulics as the second time the clutch failed the mechanic said failed slave cylinder and he replaced the slave cylinder. he was a dodgy mechanic tho so Im not sure if this was done properly. I can understand that a pressure plate could cause the clutch to burn but its a bit strange that 3 separate clutches all had poor pressure plates including a sachs which is the OEM part. I do not fully understand how the slave cylinder works but from what you describe do you mean that a faulty slave cylinder could cause the clutch not to engage fully after the pedal is released causing the clutch to slip slightly? This could very well be the cause if this is the case. Since my dad does not drive the car he has this bad habit of starting it and revving it to prevent the battery going down. If the clutch is slipping slightly could this be burning out the clutch a little every day? Mechphil no offence taken about my dad. He is quite hard of hearing now but still wants to be independent and drive himself around. One of the reasons I havent fix the car yet is also to keep him off the roads lol. I would like to get this clutch repaired in december but would like to know what to check for so I can get the problem part fixed proplerly and not continuously be replacing clutches after a few thousand km. The car is far away from me but I think there is still pressure in the clutch ie. it has not gone down to the floor as in a hydraulic leak.
MechPhil
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Alrighty! The Sachs kit is very good (and the Valeo is my first choice clutch for Japanese cars), so the problem isn't with the clutch kits then...
Yes, it seems the most popular guess here is either residual hydraulic pressure, or knackered slave cylinder, either of which would cause the clutch to not engage fully, as you said above... Since the slave cylinder was replaced, and the problem remained, my focus would shift to the master cylinder. Check if the connection between the cylinder and the pedal is adjustable. If it is, it should be adjusted to allow 10mm of "free play" at the bottom tip of the pedal. I.e. the bottom of the pedal should move down 10mm from its rest position before it starts actuating the cylinder.
Then check the breather hole in the brakefluid filler cap. It's a longshot, but it would be such an easy fix!
The clutch wouldn't slip to the point of burning from merely revving in neutral, since there's no "resistance". I can't seem to formulate what I want to say very well, but the point is, no, I don't believe the clutch can be worn out while revving in neutral.
If the gearbox and engine are misaligned, that would damage the clutch when revving in neutral!
Yes, it seems the most popular guess here is either residual hydraulic pressure, or knackered slave cylinder, either of which would cause the clutch to not engage fully, as you said above... Since the slave cylinder was replaced, and the problem remained, my focus would shift to the master cylinder. Check if the connection between the cylinder and the pedal is adjustable. If it is, it should be adjusted to allow 10mm of "free play" at the bottom tip of the pedal. I.e. the bottom of the pedal should move down 10mm from its rest position before it starts actuating the cylinder.
Then check the breather hole in the brakefluid filler cap. It's a longshot, but it would be such an easy fix!
The clutch wouldn't slip to the point of burning from merely revving in neutral, since there's no "resistance". I can't seem to formulate what I want to say very well, but the point is, no, I don't believe the clutch can be worn out while revving in neutral.
If the gearbox and engine are misaligned, that would damage the clutch when revving in neutral!
wireman
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Thanks for adding more info.
As Phil, I have some suspicion of the hydraulics.
I do not fully understand how the slave cylinder works
Its just like a bicycle pump, worked backwards with fluid being pushed into the end to push out the piston and hence actuate the clutch lever. It is a closed cylinder with a piston and seal inside it, when fluid is forced into its closed end the piston is forced outwards.
The master cylinder is almost the same, its filled with fluid and the pedal pushes its piston to force fluid into the slave cylinder. 'Tis a shade more complicated having 2 seals.
The fluid in the system must always be devoid of air space so it has to be able to get some extra fluid in or out as the mechanical parts wear or move due to thermal expansion, this is achieved by having a tiny hole in the side wall of the MC at the resting end of its stroke, fluid is supplied from the reservoir to the "snifter" hole to keep the system full of fluid, when the pedal its moved from the rest position the piston moves, cuts of the fluid supply and allows the pedal pressure to turned into the fluid pressure that operates the slave.
Incorrect installation/adjustment of the MC might possibly result in the snifter hole being obscured under some conditions which could hold pressure on the clutch release mechanism. As I noted before I'm not sure that your dads car can be adjusted, the Haynes manual says it can.
The bad habit of driving with a foot on the pedal can(will) have similar results, my dads left knee gave up on him and played havoc with his ability to take his foot away, he eventually took the plunge and went automatic (a Citroen C3, nice little car).
Beware of foisting an auto transmission on an older driver who has no previous experience of one, they need to learn about it and in advanced years this might be a big ask.
There is no need to rev up a standing car to make its alternator charge, idle will suffice if no electrical stuff is on.
As Phil, I have some suspicion of the hydraulics.
I do not fully understand how the slave cylinder works
Its just like a bicycle pump, worked backwards with fluid being pushed into the end to push out the piston and hence actuate the clutch lever. It is a closed cylinder with a piston and seal inside it, when fluid is forced into its closed end the piston is forced outwards.
The master cylinder is almost the same, its filled with fluid and the pedal pushes its piston to force fluid into the slave cylinder. 'Tis a shade more complicated having 2 seals.
The fluid in the system must always be devoid of air space so it has to be able to get some extra fluid in or out as the mechanical parts wear or move due to thermal expansion, this is achieved by having a tiny hole in the side wall of the MC at the resting end of its stroke, fluid is supplied from the reservoir to the "snifter" hole to keep the system full of fluid, when the pedal its moved from the rest position the piston moves, cuts of the fluid supply and allows the pedal pressure to turned into the fluid pressure that operates the slave.
Incorrect installation/adjustment of the MC might possibly result in the snifter hole being obscured under some conditions which could hold pressure on the clutch release mechanism. As I noted before I'm not sure that your dads car can be adjusted, the Haynes manual says it can.
The bad habit of driving with a foot on the pedal can(will) have similar results, my dads left knee gave up on him and played havoc with his ability to take his foot away, he eventually took the plunge and went automatic (a Citroen C3, nice little car).
Beware of foisting an auto transmission on an older driver who has no previous experience of one, they need to learn about it and in advanced years this might be a big ask.
There is no need to rev up a standing car to make its alternator charge, idle will suffice if no electrical stuff is on.
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MechPhil thanks again. Looks like I have my work cut out for me to check out the hydraulics. I will definately check out the filler cap as well. The clutch was burnt out during a short drive from home and never while revving in neutral. I was just trying to theorise that maybe the clutch was slowly burning out while revving in neutral and eventually burnt out when there was resistance ie actual driving. I dont think it could burn out in neutral now can it? That the gearbox and engine are misaligned there is a good chance of that as well.
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Wireman thanks for the explaination. I have a good understanding of how the brake master cylinder works so this seems quite similar. I was trying to understand how bad hydraulics could prevent the clutch from operating properly and slipping slightly due to it not fully engaging. Now that you have explained it to be similar as keeping your foot on the pedal I understand. My dad definately doesnt drive like this and used to shout at me for the same thing when I was learning. I am trying to keep him off the roads and this car is way too big for him to handle now anyways. My idea was to get a little auto just so he can go to the shops but like you said driving for such a long time with manuals he himself does not like autos. This is such a beautifully built and solid car I marvel at the engineering genius every time I look at it . I got it for my day for his 75th birthday. His prev car was a mk1 ford escort. I really dont want to sell it would like to keep it for myself someday. I remember when I was in grade 2 when the 124 series was first launched there was a tv ad saying that in 20 years time these cars will still be on the road. Its been more that 30 and they still going strong.
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