More squishy brakes

[P I Staker]

Firstly the car, its an 06 plate MK5 VW Golf.

The problems:

1. Rear drivers caliper was found to be seized, it was replaced by local garage
2. The car comes back to us with a soft pedal, sent it back in to be rebled got it back and it felt just the same.
3. Noticed the brake line to the new caliper had not been fitted correctly and was leaking fluid (No wonder they couldn't bleed it), it was sent back and the brake line was replaced.
4. Got it back and still a soft pedal
5. It needed new discs and pads all round so I did that yesterday and found the passenger side rear caliper to be siezed
6. Garage replaced caliper, comes back and pedal still feels very soft

If you press the pedal then release then quickly back on the position of the end of the travel will change but there is no other symptoms relating to master cylinder, the pedal does not sink. You can get the ABS to kick in but only softly.

I'm lost for ideas?

[gallcobair]

Have you tried changing the brake fluid? Its often a thing which tends to get neglected at service intervals.

Brake fluid has a habit of absorbing moisture through the air, which is bad news for your brakes!

Check out the service interval for brake fluid with your manufacture.

Also you could try asking another garage/mechanic to bleed the brakes in case it may have been done wrong before,

p.s. Brakes should be bled starting from the bleed nipple farist from the brake fluid bottle.

[P I Staker]

Thanks for the reply.

The brakes only became soft since the caliper was replaced so I dont think its the fluid, moisture only reduces the boiling point of the fluid anyway.

It must be air in the system, Google suggests the clutch and brakes share the same fluid and as such you must bleed the system at the calipers and at the clutch slave cylinder. Anyone know VWs and can confirm thats right?

[lgw]

The reservoir will be shared but it is partioned off inside so if you spring a leak in the clutch hydraulics you will not lose the fluid for the brakes as well

[P I Staker]

lgw said:

The reservoir will be shared but it is partioned off inside so if you spring a leak in the clutch hydraulics you will not lose the fluid for the brakes as well

Ok, so bleeding the clutch will have no effect on the brakes?

It must be then that there is still air in the braking system. Is there any reason why a garage would be unable to bleed the system properly? Are they missing a trick?

[marcus85]

P I Staker said:

Ok, so bleeding the clutch will have no effect on the brakes?

It must be then that there is still air in the braking system. Is there any reason why a garage would be unable to bleed the system properly? Are they missing a trick?

If they didn't manage to fit the brake pipe correctly and bleed the system first time then they sound rather incompetent.

[P I Staker]

marcus85 said:

P I Staker said:

Ok, so bleeding the clutch will have no effect on the brakes?

It must be then that there is still air in the braking system. Is there any reason why a garage would be unable to bleed the system properly? Are they missing a trick?

If they didn't manage to fit the brake pipe correctly and bleed the system first time then they sound rather incompetent.

It would seem that way but we have used them for ages with no real problem before.

I acquired a pressure bleeder the other day, might have a go myself.

[marcus85]

P I Staker said:

It would seem that way but we have used them for ages with no real problem before.

I acquired a pressure bleeder the other day, might have a go myself.

Maybe they were a bit rushed or someone else did the work, personally I wouldn't dream of sending a car out without checking the brakes were working properly.

[Cloggie]

If air has been introduced into the ABS valve block when changing a caliper, the car will need bleeding with a decent pressure bleeder as well as going through the bleeding procedure with a diagnostic computer.

[P I Staker]

Hmm, right ok. Thanks guys.

[Fish981]

Was the rear caliper handbrake adjusted correctly before the footbrake was used?

[P I Staker]

Fish981 said:

Was the rear caliper handbrake adjusted correctly before the footbrake was used?

I'm not sure what you mean? Usually you need to use the footbrake before using the handbrake? Anyway there's no way of me knowing as it was done in a garage.

I've not had a chance to do anything with it yet, im 80% sure it just needs bled properly...

[martycossie]

there ar 2 niples on the master clyinder un do them then bleed the brakes

[one eyed mick]

MY honest reply after watching this thread for while is bite the bullet and get the car to a VW fac agent and be prepared to spend money on the first garage's cock ups!! my op only

[Formulator]

I have a 2005 Mk5 that had the rear drivers side caliper replaced because it had seized. I had a soft brake pedal that was difficult to resolve. I used a pressure bleeder plus an assistant pressing the brake pedal at the same time to get the air out . This caliper is very hard to bleed and I had tried twice before with just the pressure bleeder without success .
Also retract piston with the special tool clockwise and bleed nipple is 11mm.

[P I Staker]

Thanks for the reply, the issue was resolved by the garage. They just needed to bleed it properly.