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Old 21st July 2021, 09:29   #16
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Re: Clutch pedal sinking

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Originally Posted by ballkey View Post
Any likely hints on what could be going wrong? Previous forum posts on other vehicles have indicated everything from full clutch replacement to master/slave cylinder replacement etc.
Appreciate any information on this.
I have been in a situation where my Clutch hydraulic assembly leaked and my clutch failed in a god forsaken place.

Trust me, that situation gave me such nightmares that I bought a Maruti as my next car.
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Old 21st July 2021, 09:29   #17
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Re: Clutch pedal sinking

Get the gearbox opened in your presence and check the plates for oil. If contaminated then there is no way other then replacing them.
If not contaminated then you could just have the slave cylinder replaced and have a good system bleeding done.
Usually service centers insist on complete replacement as its a labour intensive job to remove the gearbox etc so might as well replace all components at once.
Not required for a low run car to be honest.

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Old 21st July 2021, 09:46   #18
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Re: Clutch pedal sinking

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Originally Posted by scorpian View Post
Get the gearbox opened in your presence and check the plates for oil. If contaminated then there is no way other then replacing them.
If not contaminated then you could just have the slave cylinder replaced and have a good system bleeding done.
Usually service centers insist on complete replacement as its a labour intensive job to remove the gearbox etc so might as well replace all components at once.
Not required for a low run car to be honest.

Regards,
Manoj.
The above procedure is correct. For the life of me, I do not understand why should the flywheel be replaced? Likely that it's the costliest part. I would strongly suggest to follow and limit your ASS to the above with explicit instructions. Further, since this is a high value repair, set a pre condition that you want to be present. Else, I will not put it beyond them to show you a damaged fly wheel and say here, this needs replacement.
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Old 21st July 2021, 10:05   #19
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Re: Clutch pedal sinking

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Originally Posted by scorpian View Post
Get the gearbox opened in your presence and check the plates for oil. If contaminated then there is no way other then replacing them. If not contaminated then you could just have the slave cylinder replaced and have a good system bleeding done.
I agree with you on this.

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The above procedure is correct. For the life of me, I do not understand why should the flywheel be replaced?
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Part No.: 4 could be the faulty one splashing oil around if in case that has leaked out. Hydraulic fluid could leak onto the clutch/pressure plate which is fixed on the flywheel so any oil leakage will render the flywheel + clutch plate + pressure plate and release bearing of no use demanding a change as a full set.
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Old 21st July 2021, 10:16   #20
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Re: Clutch pedal sinking

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Originally Posted by a4anurag View Post

Part No.: 4 could be the faulty one splashing oil around if in case that has leaked out. Hydraulic fluid could leak onto the clutch/pressure plate which is fixed on the flywheel so any oil leakage will render the flywheel + clutch plate + pressure plate and release bearing of no use demanding a change as a full set.
If I am not wrong, the clutch plates can be removed and replaced with the same flywheel. You do not have to replace the flywheel. If however, they are fixed to each other, then what you say makes sense. However, that would be a very uncommon design as it would break the flywheel has to be replaced everytime the clutch plates are replaced. I have not seen a design like that.
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Old 21st July 2021, 10:33   #21
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Re: Clutch pedal sinking

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Originally Posted by handsofsteel View Post
If I am not wrong, the clutch plates can be removed and replaced with the same flywheel. You do not have to replace the flywheel. If however, they are fixed to each other, then what you say makes sense. However, that would be a very uncommon design as it would break the flywheel has to be replaced everytime the clutch plates are replaced. I have not seen a design like that.
No No what I mean is the pressure plate is bolted onto the flywheel using 6 bolts. The bolts that I am speaking about is Part No.2 in the above diagram.

After removing the gearbox, removing those 6 bolts off will free the pressure plate and clutch plate.
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Old 21st July 2021, 11:46   #22
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Re: Clutch pedal sinking

Your clutch pedal might need some but of lubrication. Go to an FNG and they'll may be do it for free.
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Old 21st July 2021, 12:19   #23
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Re: Clutch pedal sinking

Recommended to replace the failing cylinder ASAP. If not a few other problems can happen as knock on effects:

1. Clutch hydraulic circuit and the brake hydraulic circuit as usually shared. So that means the same fluid reservoir feeds both these systems. A leak in one means a leak in the other. Lost fluid means NO BRAKES in the extreme case. A failed cylinder will inevitably lead to a leak at some point if not fixed.

2. If the slave cylinder begins to leak brake oil on top of the gearbox, it can spoil the friction material and will require a complete clutch replacement. This is not a complex job but it's an unnecessary thing to deal with if it can be prevented.

3. Even before a leakage happens if the cylinder packs up in traffic, you are not going to be able to operate the clutch and will cause a stall at some point. If the vehicle stalls in traffic, you would have a hard time getting it moving again. It's not impossible but still a big pain in the neck if this happens. You would need to know the systems of your car like the back of your hand to make it work out in your favour if this breakdown occurs.
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Old 21st July 2021, 12:24   #24
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Re: Clutch pedal sinking

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Originally Posted by ballkey View Post
I took it to MsM chennai - there appears to be some oil leakage , indicating slave cylinder failure. The service advisor says the entire clutch assembly need to be replaced including the flywheel.. about 55k.🥺
The service advisor says slave cylinder failure could have leaked oil iinside and the plates could also be affected. I have asked him to inspect thoroughly after lowering the box. Will keep you folks posted
Please take a second opinion from a good FNG (someone like, BOSCH Service Centers, ExpertSpanners OMR, etc.) before proceeding with the fix offered by the MSM service advisor. You may never know, the solution may be far too simple and inexpensive than the one told by the SA.
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Old 21st July 2021, 13:33   #25
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Re: Clutch pedal sinking

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Originally Posted by sagarpadaki View Post
Unless the clutch plates are covered/contaminated with the hydraulic oil, there is no need to change the clutch. And flywheel will not get impacted with a leaking clutch slave cylinder. Just get the slave cylinder replaced and bleed the clutch and you should be good to go. Be with the service center when they open the clutch housing to check if the hydraulic fluid has seeped inside and over the clutch plates

The service center is taking you for a ride. In these Covid times, this has become a trend. Due to lack of business, the service centers are suggesting part replacements left, right and center. Just last week, I was asked to replace the entire right side suspension components - Lower arm, tie rod, link rod, strut- when I complained of noise from front right area, whereas the cause was because of the strut leaking and all other components being all right. One has to be very cautious in these times with the service centers.
True that. I could see that when I gave my '98 M800 for service. There is a substantial increase in suggesting replacements and equally substantial reduction in their workman ship levels, as well.

Quote:
Originally Posted by ballkey View Post
I took it to MsM chennai - there appears to be some oil leakage , indicating slave cylinder failure. The service advisor says the entire clutch assembly need to be replaced including the flywheel.. about 55k.🥺
The service advisor says slave cylinder failure could have leaked oil iinside and the plates could also be affected. I have asked him to inspect thoroughly after lowering the box. Will keep you folks posted
Quote:
Originally Posted by ashking101 View Post
Please take a second opinion from a good FNG (someone like, BOSCH Service Centers, ExpertSpanners OMR, etc.) before proceeding with the fix offered by the MSM service advisor. You may never know, the solution may be far too simple and inexpensive than the one told by the SA.
There are still few good FNG's luckily.
I think, I am also in search for them now a days. Subconsciously.

The last two experiences were terrible from MSM.

1. One of the Spark plugs were not tightened in April'20 service.
2. In the next service, the replaced brake pads started squeaking. My bad. I couldn't drive it immediately after receiving post service.
Found out only after a week, when I took it out for a drive.

Seems the impact of COVID is having an impact on the otherwise genuine S.A's like Raj, Balaji and Ayub at MSM, Guindy, Chennai.
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Old 21st July 2021, 15:12   #26
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Re: Clutch pedal sinking

Update: the service advisor says the Clutch plates are soaked in the oil leaked from the slave cylinder, and have to be replaced - the flywheel is okay it seems. So the flywheel stays. I've asked them to go ahead and replace the clutch plates also, don't have enough experience to judge the damage.

Thank you all for your inputs! Clutch loss is almost as panic inducing as brake loss, so I wish these parts were built better. Hopefully the new plates/cylinder will last at least another 5 years.

Last edited by Chetan_Rao : 22nd July 2021 at 10:12. Reason: typo
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Old 21st July 2021, 15:24   #27
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Re: Clutch pedal sinking

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Originally Posted by ballkey View Post
Hi , I have a 5 year old S-Cross 1.6. The car has relatively been trouble free, but in the last 1.5 years has not seen too much mileage. I do take it out at least once a week for an hour or so.
I've had the clutch pedal sinking twice while driving - thankfully at slow speeds. Both times I have been able to lift up the pedal and continue, but i am really worried on this. It drives reasonably well and there's no loss of power when it is working.

Any likely hints on what could be going wrong? Previous forum posts on other vehicles have indicated everything from full clutch replacement to master/slave cylinder replacement etc.
Appreciate any information on this.
Hi ballkey,

Did you observe any signs of spillover from your break fluid reservoir after these two incidents?

Did the fluid level in the reservoir drop after these two incidents?

If the clutch pedal sank because of oil leakage, the system would have lost oil and the hence the oil level in the reservoir must drop.

If the oil leaked from the slave cylinder, there won't be any spillover from the reservoir. But if the pedal sank because of oil leak across the master cylinder seal, the oil may splash a bit from the reservoir cap.

Last edited by Rahul Bhalgat : 21st July 2021 at 15:27.
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Old 21st July 2021, 16:23   #28
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Re: Clutch pedal sinking

Quote:
Originally Posted by ballkey View Post
Hi , I have a 5 year old S-Cross 1.6. The car has relatively been trouble free, but in the last 1.5 years has not seen too much mileage. I do take it out at least once a week for an hour or so.
I've had the clutch pedal sinking twice while driving - thankfully at slow speeds. Both times I have been able to lift up the pedal and continue, but i am really worried on this. It drives reasonably well and there's no loss of power when it is working.

Any likely hints on what could be going wrong? Previous forum posts on other vehicles have indicated everything from full clutch replacement to master/slave cylinder replacement etc.
Appreciate any information on this.
This definitely indicates either a leak in the clutch fluid or a defective/packing-up slave cylinder.

I had the same issue with my classic Mini where the slave cylinder had given up and was slowly leaking fluid. I had not noticed this and one fine day I found myself stuck at a T junction in peak London traffic, with the Mini refusing to get into any gear!
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Old 21st July 2021, 16:41   #29
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Re: Clutch pedal sinking

Quote:
Originally Posted by ballkey View Post
I've had the clutch pedal sinking twice while driving - thankfully at slow speeds. Both times I have been able to lift up the pedal and continue, but i am really worried on this. It drives reasonably well and there's no loss of power when it is working.
This is a classic slave cylinder fail. A friend of mine had the same problem but he kept on driving until this happened 600 km away from home. I managed to pressure bleed the slave cylinder and sent him on his way. Normal bleeding would not work.

He made it home and had the slave cylinder replaced.

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Old 21st July 2021, 17:12   #30
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Re: Clutch pedal sinking

Quote:
Originally Posted by ballkey View Post
I took it to MsM chennai - there appears to be some oil leakage , indicating slave cylinder failure. The service advisor says the entire clutch assembly need to be replaced including the flywheel.. about 55k.🥺
Are there any other symptoms while driving that suggest clutch functioning improperly? If there would have been any oil leakage inside the clutch assembly, you would have definately got a slippery clutch by now where the engine RPM would be higher than usual for particular speeds. And I highly doubt the need to replace the flywheel for an oil inundation.

In my experience, an MASS will always recommend replacing the entire clutch assembly whenever the unit is being opened. Maybe that's their SOP.

Will recommend you consult an FNG specifically for a slave cylinder replacement.
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