Weak Brakes

[Falconxr68]

Hi all,

I recently bought new front disks and pads from Ford so the original AU ones. I've got a 02 AU3 XR6. Now they havn't been worn in yet because the cars currently unregistered but when I took it for a spin down the court, lets say around 70 kms downhill, I had to push the brakes to the limit just to pull the car up which to me was a suprise. I didn't change the read disks or pads just the fronts. Now I know they might not be as good as aftermarket ones but how bad can they be?

* They're not worn in yet, how much of a differnce would it make when they are worn in. Also, how can I tell if I need new brake fluid?

Thanks in advance

[Mr Hardware]

Hey mate
there could be a few different problems here.
Sounds like you need to bleed your brakes. Do this with new fluid. If you don't know how to do this, don't do it yourself. Brakes are not something you should save money on.
It is also possible you've got a dead brake master cylinder.

[POELWYK]

mate the car should pull up better then what you are saying somethings not right go back though everything and check

ok to see how much Brake fluid u have open the bonnet and right up neer the firewall infront of the drivers seat you will see the brake booster have a look at the level there if its low u will need to get your hands on some DOT4 Brake fluid and top it up

[Falconxr68]

Thanks for the speedy replies, no I don't know how to bleed the brakes so I'll hopefully take the car to a mechanic to do. How much am I looking at roughly for bleeding the brakes and the master cylinder if thats the problem? Thanks for the help

[Mr Hardware]

It'll probably cost ya ~$20 in dot4 and half-hour's labour for brake bleeding
A master cylinder is about ?$250? from memory, probably an hour's labour there. The mechanic would be able to tell you if the master cylinder is ok or not pretty quickly.

[Falconxr68]

Mate just got my hands on some receipts from the work done by the previous owner on 19/03/2007. On the list its got Brake Master Cylinder $259, Brake fluid $12, and rear brake pads $38. So what do you think?

[Mr Hardware]

I think i'm pretty good on the prices!
If the master cyl was done in 07 then i doubt it'll need doing again. They're usually good for about 8 years or 200,000klms or so, but YMMV.

I'd say they just need a good bleed, like any emo kid, rite?

[Falconxr68]

haha yea you were almost spot on! Yea I'm planning to take it to a mechanic to give them a bleed and just use the brakes till they are worn in nicely, then after that invest in some aftermarket brakes!!!

[Kryton]

is the vacuum hose still attached to the master cylinder - is it broken or cracked anywhere?

Get under the car and have a look at each caliper - do you see any oil coming from any of them?

Might be time to also flush out the brake fluid and have some fresh stuff in there.
Isnt very hard to do at all, something you can easily do yourself.
If you want to know how, sing out and either myself or someone else will tell you how to do it.

[Falconxr68]

Its dark outside atm so I'll have a look tomorrow and let you know and will probably get the new brake fluid put in while the brakes are being bled. Thanks

[Kryton]

If your bleeding the brakes, then you may as well flush the fluid anyway.
2 bottles should be enough to get the job done.
Start at the LHR as that is the furthest point.
Remove most of the fluid from the reservoir first and then replace with the new stuff.
Bleed each caliper (LHR first) until clean new fluid comes through.
Make sure the reservoir doesnt get too low when you are bleeding.
Get yourself a bleeding kit as well, worth the couple of dollars.

[Mr Hardware]

Originally Posted by davway

is the vacuum hose still attached to the master cylinder - is it broken or cracked anywhere?

I think you're meaning brake booster, and it won't be that! It'd hiss like a ***** and you'd need all your might to stop the car, not all the way to the firewall like the OP says.

[FPV+fteT3]

It's a bit obvious but you did pump the brakes and push the pistons back out before your test drive? you would have to push the pistons right back to fit new pads seen this done before the brake goes to the floor first press.

[Falconxr68]

I didn't fit the pads myself the mechanics did them for me but there was brake pressure before I applied the brakes. Its just that the brake pedal feels too hard if that makes sense?

[mik]

if the cars been sitting for a while the rotors may have had a film of rust on them, causeing a bit of pad glaze.

[Falconxr68]

nah I dont leave it long enough to build up that much rust and when I took it out the rust wouldve came off by the time I put more pressure on the brakes

[Falconxr68]

bit of an update, or a lack of it. I took it to a mechanic to get my brakes checked out. I told him that the pedal felt too firm and didn't feel right. So I think he let some air out on both sides and the pedal did feel a little softer. But after i took it for a spin, I told him that they still did not feel 100%.

I'm comparing it to my brother's AU2 which has older brakes than mine and feels much better so logically there is something wrong. The mechanic told me the brakes are no good (as in the rotors) but I still think there is something else to it.

Going to take it to a brake specialist soon hopefully but in the meantime, what could be the caused, or what would you guys recommend me doing?

Cheers!

[Whoosha]

Get a new mechanic by the sound of it If he is a professinal he should have machined the rotors when the pads were fitted or at least check them for ware and informed you before you go driving that they may be sub standard. Best get it to a Brake shop soon as possible, Its to late when your embeded in a tree or some one elses car ..

[Bushbasher]

If you have a firm pedal you probably don't need to bleed the brakes as they'd feel spongy if there was air in the lines. Have you bedded the brakes in at all or are you just going on first drive impressions? There is a set procedure for bedding new pads in which usually involves getting up to a moderate speed and braking firmly down to 5kph or so then doing it again half a dozen times. Also new pads on new discs won't necessarily marry up real well and may take a few days of use to bed in and marry up properly. I just did my Fairlane and upgraded to BA slotted discs and callipers and the first time I stood on the brakes the pedal went to the floor to pull the car up. After bleeding twice and just bedding in and using the brakes they just got better and better over the next 2 days. Now they have firmed right up and pull the car up VERY well indeed but they are alot firmer than previously. That could be a couple of things including brake pad material. Some pads are softer than others and will actually compress slightly on application which will give a softer feel at the pedal.
Another possibility for your brakes is that you have somehow managed to glaze the discs first time out which will give a firm pedal but no stopping power. One way is to heat the brakes up with gentle braking instead of a good firm stop as with bedding in. Another is that the discs had a spot of oil or grease on them when fitted that was never properly washed off. The first time you hit the brakes and heat them up the oil/grease spreads all over the disc and pads and you get no stopping power and they glaze up thanks to a coating of said oil/grease. If it was me I'd check the discs to see if they're glazed, if so, a quick once over with some fine sand paper should clear it up, then go through the correct bedding in procedure. If they're ok then just drive around for a few days without taking any risks and see how they go before you start to throw money at mechanics, they may well come good with a bit of use.


Bushbasher

[bingoTE50]

I have had a similar problem on a EL . The mechanic put on a harder wearing pad,the downside was the braking efficiency was a lot worse. I would suggest you contact race brakes on this site and give them the details of rotor and pad you bought and get him to match a good set of pads that will work for you. There is normally a bed in process ,but you seem to be going now for three months.I suspect a cheap hard pad has been sold to you .

[macman]

Interesting story. Very familiar.

I have the exact same with my AU1, although mine has the Tickford premium setup up front.

The symptoms are identical and it all started after the car has stood for a few weeks, unused. The brakes were excellent before I parked the car.

I checked the fluid level - fine, checked for leaks - none, checked the pads - basically new (bendix), checked the discs (slotted) - a little glazed perhaps but otherwise fine, checked the vacuum connection to the booster - fine, checked the functionality and vacuum of the booster - also fine.

With all this in mind, I took off the pads and rotors and roughed them up. Gave the pads a lick with the bench grinder and gave the discs a rough up with some heavy sand paper. Made sure the pads went back in the same place as they were removed from and followed the brake bed-in process. Slightly better but still weak.

Brakes do not feel spongy at all, just weak. Next thing to try will be bleeding them, however I still don't understand how they were fine one day, then after standing for a few weeks were no good?

[Bushbasher]

Macman, all things being equal, if there's no other evidence of a problem I'd be looking for a seized calliper piston or indeed a partially frozen calliper next.

Bushbasher

[Falconxr68]

The thing is its well past the bedding in stage. I regret buying the standard AU3 brakes AND pads, realy big mistake, but I still can't justify the difference on the same setup in an identical car. I'll probably just take it to someone I trust and get them fixed because I don't wanna play around with brakes.

When functioning correctly, there are okay for daily driving which is why I can't justify the extra cash for aftermarket ones.

Nonetheless, thank you for your responses, I will keep you updated.

[macman]

Sorry guys, my response wasn't mean to seem like a hijack, just seemed a lot of similarities that may have given a clue as to what the cause may be.

Bushbasher, you could be right about the seized piston, would make sense! May just take it to have a professional take a look for me.

[macman]

Just thought I'd update this thread with MY solution. Cars don't like standing, doing nothing. After two days of proper driving, a couple of long stop/start trips and the brakes back to 100%.