Car not fully stopping sometimes at traffic lights

1990xrider

Mildly_Miffed said:

1990xrider said:

Garage says copper grease was put on the front brake pads which shouldn't be used, which means when the car gets heated up it won't brake fully

Copper grease is used on the edge and back of pads to enable them to move freely and reduce squeel. Silicone brake grease is better, but there's nothing *wrong* with copaslip.

If too much was used, and it'd got onto the friction faces, it'd be much more likely that you'd notice a lack of bite at speed than absolutely no brakes (but only occasionally) at very low speed.

You're speculating wildly without clue, I'm afraid.

I'm still leaning towards too much idle creep and not enough brake pedal pressure.

Well it is only very occasionally at low speed , in general the car is slower at braking than I'd expect but it can still stop. 

I'm gonna call the garage today and try and get them to actually write it up rather than rely on word of mouth 

chrisw

1990xrider said:

Mildly_Miffed said:

1990xrider said:

Garage says copper grease was put on the front brake pads which shouldn't be used, which means when the car gets heated up it won't brake fully

Copper grease is used on the edge and back of pads to enable them to move freely and reduce squeel. Silicone brake grease is better, but there's nothing *wrong* with copaslip.

If too much was used, and it'd got onto the friction faces, it'd be much more likely that you'd notice a lack of bite at speed than absolutely no brakes (but only occasionally) at very low speed.

You're speculating wildly without clue, I'm afraid.

I'm still leaning towards too much idle creep and not enough brake pedal pressure.

I'm gonna call the garage today and try and get them to actually write it up rather than rely on word of mouth 

Good idea, there's so much contradictory information in this thread that it really doesn't make sense. Too much brake fluid, faulty brake fluid, wrong type of grease, etc, etc. A lot of the issues seem to be a miscommunication or misunderstanding with the garages involved.

1990xrider

chrisw said:

1990xrider said:

Mildly_Miffed said:

1990xrider said:

Garage says copper grease was put on the front brake pads which shouldn't be used, which means when the car gets heated up it won't brake fully

Copper grease is used on the edge and back of pads to enable them to move freely and reduce squeel. Silicone brake grease is better, but there's nothing *wrong* with copaslip.

If too much was used, and it'd got onto the friction faces, it'd be much more likely that you'd notice a lack of bite at speed than absolutely no brakes (but only occasionally) at very low speed.

You're speculating wildly without clue, I'm afraid.

I'm still leaning towards too much idle creep and not enough brake pedal pressure.

I'm gonna call the garage today and try and get them to actually write it up rather than rely on word of mouth 

Good idea, there's so much contradictory information in this thread that it really doesn't make sense. Too much brake fluid, faulty brake fluid, wrong type of grease, etc, etc. A lot of the issues seem to be a miscommunication or misunderstanding with the garages involved.

From the garage: 

On inspection the vehicle BMW ____ has been fitted with new front brake pads at some point with an obscene amount of cooper grease on the brake pad sliders.

This has made its way on to the brake discs and contaminated them to the point when warm not being able to brake efficiently.

Copper grease should not be used on modern braking systems as copper and aluminium brake caliper carrier do not mix well and the amount used is here is very excessive.

The vehicle also has a sticking nsr brake caliper which will need to be replaced and the brake fluid in the vehicle is at 5% water content which will also need to be replaced.

 

So to rectify the vehicle it requires:

New front brake disc and pads

Brake fluid change

Nsr brake caliper

 

Mildly_Miffed

So the issue isn't the copper grease, but the volume of it. Very strange how it'd take 5,000 miles to work its way to the friction surface, though. You'd think the rotational forces would fling it outwards, and any heat-related spread onto the friction surfaces would be first time they got warm.

Two minutes with a can of brake cleaner and some blue paper while the pads were out would have sorted that, though - no need to replace pads, and certainly no need to replace discs.

While that rear caliper's being replaced, the fluid's being bled through that one corner, so bleeding the other three isn't a lot of extra work, especially since the front wheels are off anyway.

1990xrider

Mildly_Miffed said:

So the issue isn't the copper grease, but the volume of it. Very strange how it'd take 5,000 miles to work its way to the friction surface, though. You'd think the rotational forces would fling it outwards, and any heat-related spread onto the friction surfaces would be first time they got warm.

Two minutes with a can of brake cleaner and some blue paper while the pads were out would have sorted that, though - no need to replace pads, and certainly no need to replace discs.

While that rear caliper's being replaced, the fluid's being bled through that one corner, so bleeding the other three isn't a lot of extra work, especially since the front wheels are off anyway.

*2,000. 

The copper grease has contaminated the brake disc beyond repair, standard practise is to replace it I believe? From what I've seen online 

1990xrider

Now what do I do from here? 

Obviously the car needs to be repaired ASAP. 

AFAIK legally i have the right to demand the dealer repairs it free of charge as it is within 6 months of sale. 

However I don't actually trust the dealer to do it given they've lied to me and couldn't do something as basic as this, also it could take longer , which would mean loss of earnings for me unable to get to work. 

I'm happy to play the long game and take them to court but thinking the small claims service won't look upon it favourably if I've declined to have it repaired by the dealer? 

facade

Mildly_Miffed said:

<snip>

While that rear caliper's being replaced, the fluid's being bled through that one corner, so bleeding the other three isn't a lot of extra work, especially since the front wheels are off anyway.

With aluminium brake callipers- on a 12 year old car?  You don't touch the bleed nipples unless it is an absolute emergency! If they don't shear off they will just bring the threads out with them.

LightFlare

OP - you seem to have extraordinary bad luck with cars from a variety of directions

Have you considered a less eventful mode of transport ?

I cant see you getting anywhere with the dealer agreeing to anything and I'm not sure even small claims would either

1990xrider

So told the dealer under CRA 2015 he is responsible for repairing the car but as I don't trust him to do it, I've offered to have the car repaired myself and he can reimburse me. I have mentioned how he has technically sold me an unroadworthy vehicle, and how I will have to consider small claims action if he won't reimburse me. 

The only other option I see is he repairs it BUT with the caveat of an independent technician inspecting it after, and maybe done within a certain time frame because I need it for work. And peobably would have to ask for them to tow it as it's not fit to be on the roads. 

born_again

1990xrider said:

So told the dealer under CRA 2015 he is responsible for repairing the car but as I don't trust him to do it, I've offered to have the car repaired myself and he can reimburse me. I have mentioned how he has technically sold me an unroadworthy vehicle, and how I will have to consider small claims action if he won't reimburse me. 

The only other option I see is he repairs it BUT with the caveat of an independent technician inspecting it after, and maybe done within a certain time frame because I need it for work. And peobably would have to ask for them to tow it as it's not fit to be on the roads. 

If you have it repaired elsewhere, dealer does not have to refund you & you are introducing further complications where selling dealer can simply blame 3rd party for any issues.

TBH, if it is not doing it all the time, (it's only happened twice)  in 5K miles.. How many breaking events in 5K? Then it is not grease on the disks.
I've noticed one side of the pedal is firmer than the other = Foot slipping off pedal & releasing brakes.

I think you would have one hell of a job to prove a unroadworthy vehicle. Given mileage covered & number of times it has happened.