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Old 14th February 2015, 23:27   #16
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Default Re: Squealing brakes!

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Yes, correct and sometimes you have to, but very carefully, apply a tiny bit on the sides of the pad where it touches the caliper
Jeroen
That counts as one of the contact points between the pad and the caliper, Sir, that should always be coated with a small amount, not sometimes.
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Old 16th February 2015, 00:09   #17
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Default Re: Squealing brakes!

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That counts as one of the contact points between the pad and the caliper, Sir, that should always be coated with a small amount, not sometimes.
No, i dont agree at all. I would not go as far as saying that I have changed more brake pads than I have had cups of tea, but its pretty close.

So here is an interesting guide on how to spot your typical incompetent (brake) mechanic. The totally incompetent will not apply any paste at all. Hence, all of his customers, when Team BHP members, end up on this forum cimplaining.

The marginally incompetent mechanic will apply paste to each and every part of the pad that touches the caliper. A truly competent mechanic knows by experience which part of the pad needs paste. It varies a lot, car by car. Brake system by brake system. There is always the danger of the paste finding its way onto the brake pad with all the associated problems. So a competent mechanic knows exactly how much paste to apply to which part of the pad.

In addition, there is at least one known cause to squealing brakes, other then the lack of paste. i wrote about this in another thread. Some brake have an asymetrical cylinder. Meaining the cilinder wont apply an even force to the brake pad. Such cylinders need to be adjusted/positoned properly fromtime to time. If you dont they might squeal or they might also feel spongy, or the opposite bite pretty agressively. You need a special tool to adjust them properly.

See: http://www.team-bhp.com/forum/attach...o-img_1837.jpg

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Old 16th February 2015, 02:09   #18
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Default Re: Squealing brakes!

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Originally Posted by Jeroen View Post
No, i dont agree at all. I would not go as far as saying that I have changed more brake pads than I have had cups of tea, but its pretty close.

So here is an interesting guide on how to spot your typical incompetent (brake) mechanic. The totally incompetent will not apply any paste at all. Hence, all of his customers, when Team BHP members, end up on this forum cimplaining.

The marginally incompetent mechanic will apply paste to each and every part of the pad that touches the caliper. A truly competent mechanic knows by experience which part of the pad needs paste. It varies a lot, car by car. Brake system by brake system. There is always the danger of the paste finding its way onto the brake pad with all the associated problems. So a competent mechanic knows exactly how much paste to apply to which part of the pad.

In addition, there is at least one known cause to squealing brakes, other then the lack of paste. i wrote about this in another thread. Some brake have an asymetrical cylinder. Meaining the cilinder wont apply an even force to the brake pad. Such cylinders need to be adjusted/positoned properly fromtime to time. If you dont they might squeal or they might also feel spongy, or the opposite bite pretty agressively. You need a special tool to adjust them properly.

See: http://www.team-bhp.com/forum/attach...o-img_1837.jpg

Jeroen
The truly competent mechanic follows the procedures set the by the equipment manufacturer as being acceptable for a quality repair to their standards. That is why I said a few posts ago "assuming the diagnosis to be correct" and expressed my concerns about the quality of the repair undertaken in this thread.

It is not just the contact points or an out of round piston that can cause this problem. Glazed pads and rotors, poor quality pads and/or rotors, improper machining of the surface, deep grooves and ridges, bent shims and anti-rattle clips, missing or bent or corroded shims, the list is quite long.
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Old 16th February 2015, 15:47   #19
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Quote:
Originally Posted by VCheng View Post
The truly competent mechanic follows the procedures set the by the equipment manufacturer as being acceptable for a quality repair to their standards. That is why I said a few posts ago "assuming the diagnosis to be correct" and expressed my concerns about the quality of the repair undertaken in this thread.



It is not just the contact points or an out of round piston that can cause this problem. Glazed pads and rotors, poor quality pads and/or rotors, improper machining of the surface, deep grooves and ridges, bent shims and anti-rattle clips, missing or bent or corroded shims, the list is quite long.

Check out the official manufacturer manuals and you will be very surprised what they mention on this particular item. I own some 70-80 official workshop manuals from various car manufacturers. Most car I've owned and or worked upon.

On the matter of applying paste some don't mention it all, some mention it without any specific instructions where and how much. Only a few are specific.

This is where experience beyond the normal instruction starts playing a role.
You are quite right there are many factors that could be contributing to brake squealing as you mention. I would think the lack of paste applied at the appropriate places is the most common. My example on the piston is probably one of the more rare ones, as there are not that many cars/brake system like that. Hence, easily overlooked if you happen to have one!

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Old 23rd May 2015, 16:18   #20
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Default High Pitched Squeal new Skoda Octavia 1.8

Hi guys,

I was raving about my new Skoda Octavia 1.8TSI , about how exhilerating it is tro drive, the noise insulation, the ride, etc etc. And then of course, the Gods decided to test my ardour for my car.

The car has done only about 7000 km, and had no issues until 2 weeks back, when I started the car in the morning and began driving it, I heard a high pitched squealing sound from the left side of the car.

The sound increased in frequency as the car picked up speed and then after about 40 km an hour, it disappeared.
It also seems to get louder when brakes were applied, and doesn't seem to occur when the engine is warm.


The car drove fine otherwise and so I took it to the Skoda Service station where the problem was diagnosed as "dirt" under brake callipers or something like that.

The car came back from service. but the problem hasn't gone away.


I called the service station again, and they are going to take another look on Monday, but something tells me that they aren't sure about the cause.

Would really appreciate your expert comments - what could the cause be?

Any help and insight would be appreciated

In summary, the high pitched sound seems to be coming from the left side

a) it doesnt occur until the car is moving
b) it gets faster as the car picks up speed
c) it seems to get worse when I apply brakes
d) Seems to go away as the car is driven for a few kilometers
e) Sound disappears as the car exceeds 40 km per hour

Thanks!
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Old 23rd May 2015, 17:40   #21
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Default Re: High Pitched Squeal new Skoda Octavia 1.8

well, In my older vehicles (M800 / Fiat 1100d) the radiator fan belt used to trouble when worn out, making similar noises. it couldnt be that since your vehicle is only 7k kms old.
lets trust the A.S.S. guys. good luck.
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Old 24th May 2015, 09:17   #22
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Default Re: High Pitched Squeal new Skoda Octavia 1.8

That might be because of dirt under the brake caliper or sometimes due to rust on the disc.

I have had this issue in my Octavia twice. But since mine is a 05 Model and your's is a new one, so i am not sure whether both the tings can be connected or not. Still my 2 cents on it.

1st time: The problem occurred because a pin from the brake caliper went loose and it started making a squealing kind of a noise.

2nd time: I took out the car after it was parked for almost 2 weeks and it was washed before it got parked in the garage. So I took the car out of the garage after almost 2 weeks and as soon as i got out of gate the same noise came back again and when i pressed the brakes, noise was even higher. Took it to my mechanic and he showed me the reason why that noise was coming. There was rust on the disc plate. I drove the car for about 10-15 kms and the noise was totally gone.
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Old 25th May 2015, 13:00   #23
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Default Re: High Pitched Squeal new Skoda Octavia 1.8

Never heard of a squeal, but grating noise is common when there is dirt embedded between the disk pads and the disk. If the problem persists, just jack the car up, and use a garden hose to wash the brake calipers; and the pads/disk; thoroughly. You may have to rotate the wheel - spray water a few times to dislodge all the dirt.
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Old 25th May 2015, 14:20   #24
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Default Re: High Pitched Squeal new Skoda Octavia 1.8

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Originally Posted by shyamkb View Post
I started the car in the morning and began driving it, I heard a high pitched squealing sound from the left side of the car.
This is clearly a problem with the belt that drives the water pump otherwise known as the fan belt. The belt appears to be loose and hence the squealing when you start the car which disappears after you cross 40kmph. Ask Skoda to check the tension of the belt and tighten it to the correct torque.
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Old 31st May 2015, 10:37   #25
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Default Re: About Squealing Brakes

Thank you all for the advice and expertise.

Skoda diagnosed the issue as "brake pads that came out of the binding." on the left rear
Apparently it hasn;t happened before so they escalated it..

Brake pads replaced and the car is good as new now...


Skoda handled it well, although i am a bit concerned that this occurred in a new car...

Having said that, I am still in love with the car and highly recommend it in this category
thanks again to Team BHP!
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