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Old 15th December 2009, 15:57   #16
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Here is some more information on what could be the reason for the diaphragm spring damage.

The free-play is determined by the clearance between the throw-out bearing and the fingers. The throw-out bearing is pulled away from the fingers by the pedal return spring. As the disk wears, the fingers protrude more from the pressure plate and the free play available becomes less. When there is no more free-play, the throw out bearing will be riding on the fingers and the clutch disk, at a minimum needs to be replaced. No adjustment will make any difference. If you keep driving, the clutch will start to slip and/or the throw out bearing will wear out.

The overriding concern, is NOT free-play but over stressing the clutch diaphragm spring. If you continually over stress it, it may eventually twist and become useless and you will not be able to disengage it.

If you adjust for the free-play amount, when the clutch disk is new, you will be way over bending and over stressing the pressure plate diaphragm spring disk.

If you adjust the clutch to just barely release as the pedal touches the floor, you will not be over stressing the clutch diaphragm spring and the clutch will have the same release point for most of the life of the clutch.

Last edited by Dippy : 10th March 2010 at 08:13. Reason: Avoid copy pasting from external text editors and type out your posts correctly
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Old 9th March 2010, 20:51   #17
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Sorry rkguru for the late response. (Recession-Troubles at office forced me to go offline for some time).
Quote:
rkguru:If you adjust for the free-play amount, when the clutch disk is new, you
will be way over bending and over stressing the pressure plate diaphram
spring disk.
What you said is correct, as confirmed by one of my mechanic-friends. It seems this was the reason for my Alto clutch failure at 10,000 kms. You may refer to the picture that I posted in the previous page, showing two fingers of diaphragm spring bent.
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Old 10th March 2010, 10:10   #18
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Hi

For all who may want to know, It is difficult to know the clutch condition inside weather new or old. Also the clutch height and free play is adjustable anytime, again new or old.

The actual requirement is to have clutch properly adjusted and positioned anytime, as the clutch disk wears and also the clutch cable stretches.
My method of having this checked is as follows.

1. With the vehicle standing and engine off, first adjust the free play as per specifications, then, gently press the clutch pedal and feel what is said further...

2. As the clutch pedal is gently pressed, the free play will allow the pedal to move about an inch freely. then there is resistance felt as the throw out bearing touches the leaf spring. Gently press the pedal further against the resistance, now you are raising the pressure plate and suddenly as the plate lifts up, the resistance reduces and the pedal moves down about an inch or two further down freely. Here, now the clutch is disengaged and hold the pedal at this point.

3. This pedal position should be about two inches above the floor of the body inside.
If it is less, then further the clutch may not properly release ( a tolerance needs to be given) and if it is higher, then theoretically one needs to press the pedal fully down to release the clutch and this will put pressure on the pressure plate and damage it.

4. Now, if required, adjust the clutch pedal height to get what is mentioned in 2-3.

This is the correct position for the clutch. Not very high, so does not put extra pressure on the plates and not too low and so does not have the problem of clutch not fully releasing and so no hard gear shifts and dragging.

Now, see the difference.

Please let me know of your opinion, suggestions, and if you have tried what is mentioned above , your feedback.

Regards

Last edited by rkguru : 10th March 2010 at 10:13.
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Old 10th March 2010, 12:01   #19
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Default Top things to watch out when you give your car for service

MODS: Please feel free to move this post, I couldn't find an appropriate location when I searched.

I have consolidated some of the things done by some workshops (purposefully) to generate subsequent repair jobs, please add more from your experience:

Disclaimer: This is just a guideline for you to watch out, this doesn't mean that all workshops play foul.

All the below points (except point 3) is my own experience on my Alto, Cielo and my dad's Maruti 800.
Point 3 (regarding power steering fluid) is my friend's experience on his Santro.

Top things to watch out when you give your car for service:

1. They adjust the clutch play such that car would start moving only when you almost fully release the clutch.
Result: Within a few thousand kilometers, the diaphragm spring of the clutch assembly would fail, and you would need to replace the full clutch assembly.

2. They fill the Coolant Level above 'max' level.
Result: Due to excess pressure, the Water pump fails (this pump is used to pump coolant on the engine to reduce heat).

3. They fill the Power Steering fluid above 'max' level.
Result: This results in Power steering pump failure (not applicable to electronic power steering.)

4. They Top up the battery with tap water, rather than distilled water.
Result: This results in reducing the battery life drastically.

5. They fill engine oil above 'max' level in dip stick.
[Credits: The following information is taken from a post by 'Sideways' in this forum]
Result: Rear/front main bearing seal ruptures. Oil spills to the clutch plate. Bubbles that are formed in engine oil enter the bearings, resulting in less lubrication and failure. Excess oil gets into the piston bore and Piston rings get additional pressure and may cause damage. Oil gets in the combustion chamber and out into the exhaust system, ruining the catalytic converter. We would see oil dripping in the car porch, this is the first sign of damage.

6. They put the car in Neutral and floor the accelerator.
Result: Engine oil is pumped with high pressure due to high engine speed, and this causes pressure build up and leaks in many places. Many other things such as alternator bearing gets damaged in the long run.

7. They use 'Super Glue' on the sides of the rubber-cover on the brake caliper (this cover is called 'brake caliper boot').
Result: Next time you need to clean the brake pad or tighten the brake caliper, this rubber-cover tears apart when you try to remove it, forcing you to replace it.

8. They tighten the 'Tie Rod End' by hammering, claiming that it is loose.
Result: You would be forced to replace this hammered 'Tie Rod End' soon.
If Tire alignment can be done properly, actually there is no need to 'service' the Tie Rod End.
If Tire alignment can not be done properly due to loose Tie Rod End, it is better to replace rather than 'hammer service'.

9. They tighten the 'Lower Arm Bush' by hammering, claiming that it is loose.
Result: You would be forced to replace this hammered 'Lower Arm Bush' soon, as you start hearing 'thuds' on rough roads.

10. They bent the wires leading to the spark plug, pretending to check the 'conductivity'.
Result: You would be forced to replace these wires, because of internal breakage caused by bending. The symptom is a 'Fire Cracker' sound, as if the car runs on kerosene.

11. They tighten the alternator belt above normal.
Result: The belt would stretch and start squeaking after a few days. When you take it to the workshop, they'll tighten it again. After 3 or 4 such visits, the alternator belt breaks up, and the alternator bearing also starts showing damage (the alternator would not rotate freely). Thus, battery charging is affected and the battery gets dead soon, leaving you at the mercy of towing services.

If you have come across any other foul practice, please add to this list and spread the awareness.
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Old 10th March 2010, 15:49   #20
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Quote:
Originally Posted by rkguru View Post
For all who may want to know, It is difficult to know the clutch condition inside weather new or old. Also the clutch height and free play is adjustable anytime, again new or old.
rkguru,

A nice informative post.

Cheers,
gpa
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Old 10th March 2010, 15:56   #21
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Quote:
Originally Posted by jinojohnt View Post
I have consolidated some of the things done by some workshops (purposefully) to generate subsequent repair jobs, please add more from your experience:

Disclaimer: This is just a guideline for you to watch out, this doesn't mean that all workshops play foul.
jinojohnt,

Interesting observations. Am glad, I've not observed any of these at my local MASS. Though at the last service, they overfilled the engine oil in my Alto and I had to visit them 2 days after the service to get the excess drained.

But then again, this is my experience since I'm always present at the MASS when my car is being serviced.

On the clutch failure you experienced - Something almost identical happened to my Alto in May 2009 less than year after I bough the car at ~14,400 kms on the ODO. I got all the parts replaced under warranty and didn't have to pay anything. The clutch failure of the Alto has been recurring with increasing frequency in the recent past. The mechanic admitted that the failure was due to a manufacturing defect.

Apologies on this late reply, as I saw this thread just now. Have you taken up the matter with MUL?

Regards,
gpa
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Old 10th March 2010, 16:14   #22
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Quote:
Originally Posted by jinojohnt View Post
1. They adjust the clutch play such that car would start moving only when you almost fully release the clutch.
Result: Within a few thousand kilometers, the diaphragm spring of the clutch assembly would fail, and you would need to replace the full clutch assembly.

2. They fill the Coolant Level above 'max' level.
Result: Due to excess pressure, the Water pump fails (this pump is used to pump coolant on the engine to reduce heat).

This is how the clutch is set in my Alto. In fact that is how it came from the factory. When I told the dealership that it was a little difficult for me, the service guys said the play is correct as per the recommendations in the manual. So I took the car for the first service to a different MASS and they also maintained the same setting and confirmed it is the correct/recommended play. I was given to understand that if the clutch is adjusted to to engage below the half way mark, it causes the the clutch plates to fail much sooner.

So I checked the setting in my BIL's 6 year old Alto. Identical setting here as well. He told me that is how it was ever since he bought the car. The car has clocked 23k KM so far with the original clutch. So I conclude any premature failure must be caused by fiddling with the play and/or mfg defect.

I also seriously doubt the point about excessive pressure buid-up in the radiator. Coolant from the reservoir can enter the radiator only if the level there goes down. If the radiator is full, the high level of coolant in the reservoir can at best cause an overflow, IMO.
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Old 10th March 2010, 18:10   #23
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Quote:
GPA: On the clutch failure you experienced - ..... ..... Have you taken up the matter with MUL?
I keep writing to what ever MUL addresses I get hold of, till now no luck.
I have slowly started loosing interest, as I doubt whether it's worth the pain for 3000 Rs.

Quote:
Gansan: I also seriously doubt the point about excessive pressure buid-up in the radiator.
Can somebody comment on this? I heard this point about water pump failure from a mechanic only. Even other wise, I feel this could lead to leaks because of increased pressure in the coolant reservoir... What do you think?
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Old 10th March 2010, 19:06   #24
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Quote:
Originally Posted by jinojohnt View Post
I keep writing to what ever MUL addresses I get hold of, till now no luck.
I have slowly started loosing interest, as I doubt whether it's worth the pain for 3000 Rs.


Can somebody comment on this? I heard this point about water pump failure from a mechanic only. Even other wise, I feel this could lead to leaks because of increased pressure in the coolant reservoir... What do you think?
Dude, the coolant reservoir is not air-tight; the radiator is. If you look closely at the connecting tube between the radiator and the coolant (overflow) reservoir, the connection at the radiator is located higher than the one in the reservoir. The evaporated water from the radiator will condense in the reservoir, and will be sucked back in to the radiator when needed. Where does the question of pressure arise?
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Old 11th March 2010, 12:19   #25
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Quote:
Gansan: the coolant reservoir is not air-tight; the radiator is.
Oh, ok. I thought the reservoir would also be under pressure because when I try to slowly open the reservoir cap after the engine is heated up, it sounds like opening a cola bottle.
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Old 15th March 2010, 11:56   #26
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I opened the Coolant resevoir for my cars over the weekend, and noticed the following:

1. Dad's Maruti 800 - Reservoir is not airtight
2. My Cielo - Reservoir is airtight, sounds like opening cola bottle when engine is hot
3. My Alto - Reservoir is airtight, sounds like opening cola bottle when engine is hot

Does this mean that it's different for different cars? In that case, do we need to be careful not to overfill the reservoir when it is airtight by design?

It could still be that 'airtight' is just my perception - can some Cielo/Alto owners comment on this?
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Old 15th March 2010, 12:36   #27
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I think it is only your perception. If the coolant can overflow, then it can't be air-tight.
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Old 23rd March 2010, 11:40   #28
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Default Top things to watch out when you give your car for service

Quote:
Originally Posted by jinojohnt View Post
I have consolidated some of the things done by some workshops (purposefully) to generate subsequent repair jobs, please add more from your experience:
1........
2........
Here's point 12 - this time it's by the dealers, not the workshop:

12. Almost all cars that I used for a test drive, had their speedo meters disconnected. Obviously these cars would go to some unsuspecting owner - how to avoid this?
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Old 23rd March 2010, 11:44   #29
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Go with the reputation of the dealership. Avoid ones that don't have separate TD cars. Ensure the mfg date is no more than two months prior to date of purchase. They will tend to give the oldest cars for TD first.

Last edited by Gansan : 23rd March 2010 at 11:50.
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Old 23rd March 2010, 14:52   #30
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I had test drives on two i10 kappa's near my office complex, provided by the only 2 hyundai dealers at Trivandrum. Both were non-TestDrive vehicles (no stickers), and both had their speedo meters disconnected. When questioned, the answer is "It is indeed a TD vehicle sir, the speedo is not working because it is yet to be serviced".

The purchase date of my Alto was 16 Aug, and the manufacturing date is given as August of the same year (Means the car was manufactured less than two weeks before I purchased). Yes, it was from a reputed dealer that has separate TD cars. I had a heart break when I reached home to find that the speedo was disconnected (I took delivery just before shop closing time), but the sales rep vouches that the car has not been used for Test Drives, the maximum may be that the car was put on display at the showroom. Unfortunately, there's a limit to how much one can fight after taking delivery of the car, right?
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