Volvo Community Forum. The Forums of the Volvo Owners Club

Forum Rules Volvo Owners Club About VOC Volvo Gallery Links Volvo History Volvo Press
Go Back   Volvo Owners Club Forum > "Technical Topics" > S80 '06-'16 / V70 & XC70 '07-'16 General

Notices

S80 '06-'16 / V70 & XC70 '07-'16 General Forum for the P3-platform S80 and 70-series models

Information
  • VOC Members: There is no login facility using your VOC membership number or the details from page 3 of the club magazine. You need to register in the normal way
  • AOL Customers: Make sure you check the 'Remember me' check box otherwise the AOL system may log you out during the session. This is a known issue with AOL.
  • AOL, Yahoo and Plus.net users. Forum owners such as us are finding that AOL, Yahoo and Plus.net are blocking a lot of email generated from forums. This may mean your registration activation and other emails will not get to you, or they may appear in your spam mailbox

Thread Informations

Spongy brake pedal after changing pads and disks

Views : 3339

Replies : 10

Users Viewing This Thread :  

Reply
 
Thread Tools Display Modes
Old Oct 22nd, 2017, 09:18   #1
John Child
John
 

Last Online: Oct 22nd, 2017 09:18
Join Date: Oct 2017
Location: Brighouse
Default Spongy brake pedal after changing pads and disks

I changed my front brake disks and pads on my 2012 V70 D3 yesterday and subsequently found that I have a spongy brake pedal. When I start the car I find that the pedal can go straight to the floor but if I pump it a couple of times it is ok. However it will then loose pressure shortly after. When fitting the brakes I did not bleed them as the pistons were able to move back easily and the you tube links I watched did not show that this was required. I changed the rear pads and disks a couple of weeks ago and I did not experience this problem. Any help is greatly appreciated.
John Child is offline   Reply With Quote
Old Oct 22nd, 2017, 09:27   #2
Whyman
Premier Member
 

Last Online: Today 10:21
Join Date: Nov 2013
Location: Newark
Default

Try bleeding the fronts.

It is always worth pumping out the fluid in the pistons at each pad change as it works hard and can deteriorate over time and certainly doesn't help pushing it back into the master cylinder, and it may cure the problem.
__________________
XC60 2013 D5 215 SE Lux Nav geartronic
Whyman is offline   Reply With Quote
The Following User Says Thank You to Whyman For This Useful Post:
Old Oct 22nd, 2017, 10:46   #3
Model flyer
Master Member
 

Last Online: Dec 15th, 2023 19:46
Join Date: Jan 2006
Location: Kent,pothole capital of UK.
Default

That definitely sounds like air in the system and will need a thorough bleed front and back. You may have to go around it a couple of times to get a good pedal. Expect to use about a liter of fluid this will give the system a good flush. If it's still the same after bleeding then you may have damaged a seal in the master cylinder when you pushed the pistons back. You should have clamped the flexible hoses and released the bleed nipples before pushing the pistons back . This releases the pressure and any contaminated fluid in the wheel cylinders is expelled. Hope it goes well.
__________________
The secret of flight is to aim at the ground and miss !

Previous Volvos 740 GLE . V40 CD ,V70 2.4 SE LPT.V70 D5 P2. V70 D5 Se Lux P3. Current Jaguar XF Sportbrake but still like Volvos
Model flyer is offline   Reply With Quote
Old Oct 22nd, 2017, 13:24   #4
cheshired5
Premier Member
 

Last Online: Dec 26th, 2021 14:42
Join Date: Dec 2013
Location: Crewe
Default

OP, if you use youtube as a definitive guide to brake pad changing and you do nothing with fluid changing and bleeding, you shouldn't be working on a braking system.
__________________
2002 S60 SE D5 Manual
209000 miles
cheshired5 is offline   Reply With Quote
The Following 2 Users Say Thank You to cheshired5 For This Useful Post:
Old Oct 22nd, 2017, 17:37   #5
pookie
Premier Member
 
pookie's Avatar
 

Last Online: Apr 2nd, 2021 22:13
Join Date: May 2006
Location: Stockport
Default

How did you retract the caliper pistons into the caliper? If you just pushed them back into the caliper, it has been known for the fluid pushed back into the master cylinder to "flip" the rubbers in the bore. When pushing the cylinders into the caliper ALWAYS open the bleed nipple. This will protect the master cylinder.

Salut!

Pookie
__________________
Growing old disgracefully
pookie is offline   Reply With Quote
Old Oct 24th, 2017, 14:52   #6
Waynedance
Senior Member
 

Last Online: Mar 15th, 2021 23:31
Join Date: Jun 2017
Location: Nuneaton
Default

Work at a garage and see this lots, poor brakes after driveway fixers been at the brakes.

Had a car in last week for an MOT retest and the front pads were only touching two thirds of the disc, they fitted incorrect smaller discs.

As said has been known to take out the brake master cylinder, get the car to a garage if the brakes do not feel right.

Ps. not say the op is as bad as the example above.
__________________
S80 P3 SE LUX D5 Auto
Waynedance is offline   Reply With Quote
Old Dec 13th, 2017, 10:17   #7
Elmer Fudd
Junior Member
 

Last Online: Jan 28th, 2023 01:26
Join Date: Dec 2017
Location: Canterbury
Default

Quote:
Originally Posted by pookie View Post
How did you retract the caliper pistons into the caliper? If you just pushed them back into the caliper, it has been known for the fluid pushed back into the master cylinder to "flip" the rubbers in the bore. When pushing the cylinders into the caliper ALWAYS open the bleed nipple. This will protect the master cylinder.

Salut!

Pookie
Hi Pookie,

I've just had new front discs and pads (Borg & Beck) fitted to my 12 plate V70 D5 auto by my local independent dealer. I've now got a very similar situation where the brake pedal feels much spongier than before. I took the car back the next day suspecting that somehow air had gotten into the system, the same guy bled the brakes and showed me there was no air in there? He seemed to think all was OK and that braking efficiency would improve with time?

I was advised these discs come with a coating that takes a while to wear off but I've now done 500 miles and while the brakes seem a little better they are far from what they were... The car brakes OK but you have to use much more pedal pressure than before. Also when I pump the brakes with the engine running the pedal goes hard but then gradually pushes down towards the floor. With the engine off the brake pedal goes rock solid and stays that way - again the mechanic reckons that is normal for an auto and shows the brake servo is working OK but I've never noticed it before (although probably never had the need to pump the brakes before!) Is this normal?

I have spoken to two mechanics about opening the bleed nipples when you push the pistons back in and neither of them had ever heard of doing this? Likewise when I mentioned the rubbers may have 'flipped' if the pads are pushed back without opening the nipples they reckoned they had never heard of this either!

Assuming the rubbers in the master cylinder have reversed,. is there any way this can be fixed or is it a new master cylinder jobbie?

Look forward to hearing back from you or others - thanks!

Last edited by Elmer Fudd; Dec 13th, 2017 at 10:35.
Elmer Fudd is offline   Reply With Quote
Old Dec 13th, 2017, 18:10   #8
green van man
Premier Member
 

Last Online: Feb 7th, 2024 11:00
Join Date: Nov 2012
Location: Ffos y Ffin
Default

I have heard about this rubbers flipping when you push the piston back thing, not convinced myself unless the master cylinder has a tapered bore.
The fluid pushing back into the master cylinder is the same as the master cylinder pushing the fluid out.

I confess I have never had cause to strip a Volvo master cylinder, all the ones I have, come with one or two seals on the piston dependant upon single or twin circuit, neither of which have room to flip when fitted to the cylinder, if they did have they would certainly flip when brakeing.

A spongy pedal can be caused by the new pads not being bedded in, long travel can be caused by the disk not being fitted square. Did you grease/ copper slip the mateing surfaces of the disk and hub? If so this may be the cause of your problems as it can cause the disk to be mounted out of square and give pad knock back, you then have to make up this extra clearance every time you brake giving you long peddle travel. Disks should be fitted to the hub dry, it is OK to grease the mounting spigot on the hub lightly to prevent the wheel sticking.

Quick test of a servo is to pump the peddle with engine off until it goes hard, start engine and peddle should move towards the floor as vaccuum biulds. It's a test I perform regularly on my vehicles, a longer time to build vaccuum than usual indicates a failing vaccuum pump or some other issue that needs investigation.
I change my brake fluid every 2 years so should have no moisture ingress problems but old fluid that has absorbed moisture can also give a spongy peddle.

It looks as if it's something you've done or the parts you've fitted that has caused the problem as it was fine previously. If you greased the hub/disk mating surfaces I would be stripping them and washing the grease off with brake / clutch cleaner or petrol, if not I would be stripping them and checking carefully every component as I rebuilt it.

If it comes to stripping the master cylinder then I would be looking for a service pack of new seals rather than a new cylinder if possible, it's a Volvo, they want £85 for a disc, eyes will water at the price of a master cylinder.

I most certainly would not be handing it over to a garage at this point, if you can find where you went wrong you will never make the mistake again, have someone else fix it and you will never learn.

Paul.
green van man is offline   Reply With Quote
Old Dec 14th, 2017, 11:41   #9
Model flyer
Master Member
 

Last Online: Dec 15th, 2023 19:46
Join Date: Jan 2006
Location: Kent,pothole capital of UK.
Default

Does the brake caliper carrier move freely on its sliders ? This allows the caliper to align with the pad and disc .If it stiff or stuck this can cause the problem you describe as it springs the caliper and piston back after the pedal is released causing the excessive pedal travel to take up the slack. Haveing the car cleaned by so called " hand car washes" that use pressure washer can cause the problem . Check all parts are clean ,lubricated and move freely . Any run out of disc or wheel bearing play can also cause this problem. Some pads can take what seems like an age to bed in so if all is well and your sure there's no air in system ( bleed all of the system not just the front this may take two or three circuits of the car ) then give pads time to bed and braking should improve.
__________________
The secret of flight is to aim at the ground and miss !

Previous Volvos 740 GLE . V40 CD ,V70 2.4 SE LPT.V70 D5 P2. V70 D5 Se Lux P3. Current Jaguar XF Sportbrake but still like Volvos
Model flyer is offline   Reply With Quote
Old Jan 11th, 2018, 22:14   #10
big square car
Member
 

Last Online: Today 18:54
Join Date: Aug 2012
Location: hillsborough
Default

John Child, did you manage to get your brakes sorted? If so what was the problem?
big square car is online now   Reply With Quote
The Following User Says Thank You to big square car For This Useful Post:
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 19:53.


Powered by vBulletin
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.