I have messed up my brakes. Need advice please

[Dande]

Hi guys,

So I think I have messed my brakes up after changing the rear pads. The mistake I made was that I pumped the brakes after putting the cap back on. Well I think that's what is wrong. 

I took it for a short drive and it seemed mostly ok. But when I stopped with the engine running the brake pedal was making a slight hissing noise when pressed and if I kept my foot on it then it would go all the way to the floor. Then the next second it was sort of ok.

Have I pushed air into the system and now I need to bleed it?

I feel really stupid as it is such a simple thing and I have done brakes so many times. 

Luckily I bought some transparent tubing for just in case I had an issue.

Can someone please advise.

[Stivino]

16 minutes ago, Dande said:

The mistake I made was that I pumped the brakes after putting the cap back on.

That shouldn't cause a problem.

Did you open any nipples?

[Dande]

17 minutes ago, Stivino said:

That shouldn't cause a problem.

Did you open any nipples?

No I didn't touch any of them. I just took the brake fluid cap off then pushed pistons back with old brake pads then I put the new ones in with new clips.

[Stivino]

Then, you've done nothing wrong.

If you're sure that you did everything you are supposed to do, you just might need to wait until you get used to the feel of the new pads.

[Dande]

27 minutes ago, Stivino said:

Then, you've done nothing wrong.

If you're sure that you did everything you are supposed to do, you just might need to wait until you get used to the feel of the new pads.

Thanks. I hope so. I am getting worried that I damaged the brake lines or something when taking the carrier off. I am quite a careful person so I don't know.

 

I heard a bit of an air type noise from the passenger side rear but I cant find any leaks

[Derek.w]

You need to bleed them best to have a mate push the pedal 2 or 3 times holding it in the down dosition now with the tube in a jar crank open the bleed screw then close it when fluid slows down the pedal also moves down slightly repump pedal and do it again when happy do the same on the other side.

If the pedal now feels normal job done if not bleed the other 2 wheels & do regular checks on fluid level as you dont want it dropping low at any point when bleeding or you have to do it all again.

[Stivino]

If you only changed the pads and didn't open any nipples, there is no need to bleed anything. 

[Dande]

Well I didn't open anything that I know of unless I caused a leak somewhere.

I need to check the passenger rear caliper because on a short drive I could hear some sort of noise from that direction. Not much but ot was like an air type noise. It was probably just the pads scrapping slightly as it went away. Brake fluid level seems ok too.

I just hope it's not the master cylinder or something expensive as I lost my job recently.

[DerekHa]

It could take a few weeks for the new brake pads to bed into the old rear brake discs/rotors, more so if the the rotors are well worn. While bedding in the new pads will tend to make the brake pedal feel like there's more travel than usual or a little spongey until they've conformed to the old rotors and leave you with less effective braking until fully bedded in.

Another thing to consider, you don't mention it, but cleaning off the old stainless steel springs and where they locate is best as this can cause the new pads to not come into full contact with the old discs. That could account for the initial sinking brake pedal you experienced, as one or more of the pads were pushed further home and into better contact with the disc(s).

[Dande]

26 minutes ago, DerekHa said:

It could take a few weeks for the new brake pads to bed into the old rear brake discs/rotors, more so if the the rotors are well worn. While bedding in the new pads will tend to make the brake pedal feel like there's more travel than usual or a little spongey until they've conformed to the old rotors and leave you with less effective braking until fully bedded in.

Another thing to consider, you don't mention it, but cleaning off the old stainless steel springs and where they locate is best as this can cause the new pads to not come into full contact with the old discs. That could account for the initial sinking brake pedal you experienced, as one or more of the pads were pushed further home and into better contact with the disc(s).

Yeah thanks mate. Maybe I am worrying too much. I did fit 8 all new springs as they came with the brakes.

My discs are a little scored as well. Would that make a difference?

[DerekHa]

5 minutes ago, Dande said:

Yeah thanks mate. Maybe I am worrying too much. I did fit 8 all new springs as they came with the brakes.

My discs are a little scored as well. Would that make a difference?

Yes scoring will make a difference but given a week or two of normal driving the pads will wear and take on the profile of the scored discs. Have done the same as you in the past when money was tight and the brake padal always firmed up. Just take things easy when braking initially.

Getting new springs is always better than relying on cleaning up the dirty/rusty old ones. Some copperease on the contact points will help stop the pads binding in the calipers, don't get it on the brake material or the discs though!!

Good luck Dan.

[Derek.w]

If the brake pedal is travling to far down do bleeding operation asap as it wont improve when pads are bedding in.

I hope you have not fliped the seals on the master cylinder.

[Stivino]

11 minutes ago, Derek.w said:

If the brake pedal is travling to far down do bleeding operation asap as it wont improve when pads are bedding in.

I hope you have not fliped the seals on the master cylinder.

That's a complete word salad.  No need to bleed and impossible to "flip" seals.

[Derek.w]

Bleed nipples are easy to snap off if this is the first time for lets say 4 or 5 years since it was last opend.

If so it may just pay you to remove the callapers altogether then heat up the bleed nipple and cool it down with water then repeat it 2 or 3 times then crack open the bleed nipple.

Hope this info helps!.

[Dande]

Ok, so I have been for a few drives and the braking seems to be as least as good as before but I haven't tested heavy braking obviously.

The thing it is doing that makes me nervous is when I get home and it's at idle, the peddle will slowly sink to the floor if you keep pressure on it. 

I don't want total brake failure down the line. 

[Gerg]

1 hour ago, Dande said:

the peddle will slowly sink to the floor if you keep pressure on it. 

Just my two penn'orth...

When you are using the car normally, the pressure you apply to the brake pedal is adjusted (without very concious thinking, unless you are a learner driver), by how quickly the car slows down. 

But, when the car is parked, you are focusing on the brake pedal only.  You probably apply more pressure when to the brake pedal when parked than you would do in 'normal' driving, so the pedal moves further than you expect.

Also, as DerekHa mentions above, until the pad surfaces bed in to the old disk's wear profile (your part-worn disks will have become slightly triangular in cross-section, but the new pads will be 'square'), there may be some extra slight flex/give in the wearing components, at least until the brake pressure is allowed (through normal wear) to spread the load across the whole face of the new pad.  The hydraulic system will magnify that flex when viewed at the brake pedal - which can be alarming.

I don't know your model of Toyota at all, was a piston wind-back tool not needed? 

If the pistons have been rotated (deliberately) to 'wind them in', then they may need aligning.  This, so a rebate in the piston can engage with the shallow 'pin' that will be on the back of the piston-facing pad.  If not done correctly, this can cause problems of uneven pad wear, and possibly poor brake 'feel'. 

Your brakes might not have this arrangement though, but it is common, and often overlooked, as sometimes reported on the Avensis forum here.  The Verso might use a secondary, small, drum brake for the handbrake, in which case they won't have that arrangement.

But, the above is entirely my own opinion from doing my own brakes.  I'm not a professional, and I'm always happy to learn from others experience!

[Stivino]

NO wind back tools are required.  This car has the same set-up as my Avensis,i.e. the handbrake is inside the rear drum. Like that.

Wait until the pads bed in and all will be fine.

[DerekHa]

10 hours ago, Dande said:

Ok, so I have been for a few drives and the braking seems to be as least as good as before but I haven't tested heavy braking obviously.

The thing it is doing that makes me nervous is when I get home and it's at idle, the peddle will slowly sink to the floor if you keep pressure on it. 

I don't want total brake failure down the line. 

Hi again Dan,

Have just been reading your latest post on your brakes and the pedal still going to the floor stationary and with engine at idle. Am sure I've come across this in the past but can't for the life of me remember which vehicle!

Try taking a look at the brake servo unit. It will have a hard plastic pipe running to it, it's a vacuum hose/pipe and it's that vacuum that provides the extra braking effort needed on disc brakes. Check that the vacuum pipe is in place correctly and fully pushed home into the brake servo assembly. It's possible when working on the master cylinder reservoir you may have disturbed the pipe connector. You also described a hissing sound which could easily be the vacuum leaking out of the servo unit.

Can't speak for the Corolla Verso but most vehicles I've had the vacuum hose ends with a plastic fitting which pushes into the servo and has a rubber seal to keep the vacuum produced inside the servo unit. Petrol engines usually rely on the inlet manifold to provide the vacuum but diesels I believe have a seperate vacuum pump for this.

It's also possible you could have a faulty servo unit but sounds like it was ok before you started work on the rear pads. Best to rule out the simple stuff first.

Found an image of what I think will be the same as your servo unit, of the Bay, you can see the vacuum pipe attached but it's been cut in this image. Hope this helps.

[Dande]

14 minutes ago, DerekHa said:

Hi again Dan,

Have just been reading your latest post on your brakes and the pedal still going to the floor stationary and with engine at idle. Am sure I've come across this in the past but can't for the life of me remember which vehicle!

Try taking a look at the brake servo unit. It will have a hard plastic pipe running to it, it's a vacuum hose/pipe and it's that vacuum that provides the extra braking effort needed on disc brakes. Check that the vacuum pipe is in place correctly and fully pushed home into the brake servo assembly. It's possible when working on the master cylinder reservoir you may have disturbed the pipe connector. You also described a hissing sound which could easily be the vacuum leaking out of the servo unit.

Can't speak for the Corolla Verso but most vehicles I've had the vacuum hose ends with a plastic fitting which pushes into the servo and has a rubber seal to keep the vacuum produced inside the servo unit. Petrol engines usually rely on the inlet manifold to provide the vacuum but diesels I believe have a seperate vacuum pump for this.

It's also possible you could have a faulty servo unit but sounds like it was ok before you started work on the rear pads. Best to rule out the simple stuff first.

Found an image of what I think will be the same as your servo unit, of the Bay, you can see the vacuum pipe attached but it's been cut in this image. Hope this helps.

Thanks a lot for your help mate. That is the same yeah. I have had a look at this and surrounding area and I can't see a problem anywhere or any noises or leaks anywhere to do with the brakes.

The car drives and brakes well. In hindsight I can't say for sure that my car was not this way before I changed the pads. I might have just noticed it yesterday because I was more aware and had to pump the pedal.

Maybe I was just overthinking it which os quite like me.

 

[Stivino]

Servo, it's a diesel, won't it have a vacuum pump?

[DerekHa]

29 minutes ago, Stivino said:

Servo, it's a diesel, won't it have a vacuum pump?

 

From what |I remember of my diesels  (now driving a petrol) and from what I've been reading seems diesels use a vacumm pump but still have a brake servo unit.

By the way Stephen I like your new Icon, my sentiments entirely on that! 👍

[DerekHa]

34 minutes ago, Dande said:

Thanks a lot for your help mate. That is the same yeah. I have had a look at this and surrounding area and I can't see a problem anywhere or any noises or leaks anywhere to do with the brakes.

The car drives and brakes well. In hindsight I can't say for sure that my car was not this way before I changed the pads. I might have just noticed it yesterday because I was more aware and had to pump the pedal.

Maybe I was just overthinking it which os quite like me.

 

[DerekHa]

Ok that sounds good Dan. I've been guilty of overthinking things myself more than once!

Might be an idea though to have someone sit in the car with foot on the brake with engine idling while you listen for that tell tail hiss which you may not now hear. Hopefully you'll hear nothing and it's just a case  of letting the pads bed in fully.