New brakes + disks,Spongy.

Nevakonaza · 18 Jan 2014 at 18:31

Old man got new Brake disks & pads fitted today,Although he said they feel spongy and don't slow down all that quick he really has to squeeze the pedal.

Normal as they need to wear in?

Dabbles · 18 Jan 2014 at 18:51

Air in the lines?

pepsilol · 18 Jan 2014 at 19:12

Did it include a brake fluid change?

If not they just need bedding in and will firm up. Some are just like that, some are firm straightaway.

If no BF change then something is seriously wrong. Has he checked the fluid level incase a line was nicked and it's leaking?

Liquidfox · 18 Jan 2014 at 19:21

When you first get new disks and pads everything will be really soft and seem broken for the first 10-20 miles at least. Mine sorted themselves out come the end of the 40 mile drive home.

Fuzz · 18 Jan 2014 at 19:44

Pads haven't bedded into the discs yet, that is all.
If they weren't spongy before the brake change then it wont be the fluid full of air or anything.

A brake fluid change may help if the fluid is old and contains a fair amount of moisture but is not and cannot be "caused" by a disc and pad change.

Django x2 · 18 Jan 2014 at 21:08

^ that makes no sense. Changing pads / discs is the most common way of introducing air into the system and therefore should be checked / bled usually as a matter of course

SHEDDER1uk · 18 Jan 2014 at 21:10

Changing discs and pads should not introduce any air into the system. All your doing in pushing the piston back in on the caliper.

Fuzz · 18 Jan 2014 at 21:14

Django x2 said:
^ that makes no sense. Changing pads / discs is the most common way of introducing air into the system and therefore should be checked / bled usually as a matter of course

It is you who is making no sense.
Do tell me where this air gets in when you replace pads and discs?

pepsilol · 18 Jan 2014 at 22:31

SHEDDER1uk said:
Changing discs and pads should not introduce any air into the system. All your doing in pushing the piston back in on the caliper.

touch · 18 Jan 2014 at 22:42

pepsilol said:

It's a closed system. If you dont open it, then you cant get air into it.

SHEDDER1uk · 18 Jan 2014 at 22:46

I was a mechanic for 7 years and never had to bleed a system on a disc and pad change.

Housey · 18 Jan 2014 at 23:36

It is most likely due to the pad not bedding in yet. I have no idea how your dad drives or how many miles so can't tell you how long it takes for him to bed them in, but he will feel he needs to dig for them if he brakes hard and they won't retard as well until they are bedded.

Fuzz · 18 Jan 2014 at 23:39

Dabbles said:
Air in the lines?

pepsilol said:
Did it include a brake fluid change?

If not they just need bedding in and will firm up. Some are just like that, some are firm straightaway.

If no BF change then something is seriously wrong. Has he checked the fluid level incase a line was nicked and it's leaking?

Django x2 said:
^ that makes no sense. Changing pads / discs is the most common way of introducing air into the system and therefore should be checked / bled usually as a matter of course

I suggest you lot......
http://www.truro-penwith.ac.uk/pt/basic-motor-vehicle-mechanics-2/

viper_2003 · 19 Jan 2014 at 08:59

Might be worth checking that the retaining clip that keeps the pads in place is located properly. I did a pad and calliper change once and didn't do that resulting in brakes that felt very soft much like air in the system, no amount of bleeding would shift it but taking it to bits and starting again sorted it.

Dr Who · 19 Jan 2014 at 10:19

New Pads and Discs do not have even contact surfaces so to get good contact some flex takes place until both are bed in, this results ina spongy feel to the pedal. Once they are bed in, it should feel like normal.

Lopéz · 19 Jan 2014 at 12:29

Django x2 said:
Changing pads / discs is the most common way of introducing air into the system

No it's not. Have you ever changed a set of brake pads?

Django x2 · 19 Jan 2014 at 12:58

Yes, winding in a caliper, incorrectly, will introduce air into the system.

I changed pads on a mk4 golf and no matter how careful I was, the brakes were complete cheese afterwards. A quick brake bleed all round solved the issue.

TaKeN · 19 Jan 2014 at 13:31

Err Wut? Never had that happen to me before..

Fuzz · 19 Jan 2014 at 14:46

Django x2 said:
Yes, winding in a caliper, incorrectly, will introduce air into the system.

I changed pads on a mk4 golf and no matter how careful I was, the brakes were complete cheese afterwards. A quick brake bleed all round solved the issue.

If you are retarded enough to pop one of the pistons out while pushing the other back in then yes, you would introduce air into the system obviously.
However you simply cannot get air into a closed system by simply pushing the pistons back normally.
I suggest you probably had a section of rusty master cylinder that the seal normally doesn't get used in normal operation but when you replaced the pads and had to "pump up" the pedal" you disturbed that rust which in turn caused the seal to be somewhat inefficient until you had bled (pumped) the pedal a bit more and re-seated it.
Air - impossible
Crap - highly possible if the system isn't serviced regularly