Spongy Brakes

[Bubbles]

I know this isn't stricky Galaxy related but I'm hoping one of you technical boffins can help me out of this pickle

I've just changed the front brake disks on my wife's Rav4 (a job I have done several times before on various cars over the years)

Bled the system (with engine off) and the resevoir is at correct level

The brake pedal is nice & firm (as it should be) until the engine starts running

Then, brakes become incredibly spongy and I'm sure wouldn't stop me properly at speed

There is no sign of air anywhere or leaks

Can you help me? am I missing something blatently obvious?

Car is off the road now and 'her who must be obeyed' is really chuffed that she will have to walk the kids the 2 miles to school tomorrow

[wood73]

how did you bleed them?

a lot of these newer cars should be bled using a pressure bleeder, as the seals in the master cylinder dont hold up very well to conventional bleeding.

if bleeding the old way it should ideally be done with the engine running.

hope this helps

[RADIOTWO]

I know this isn't stricky Galaxy related but I'm hoping one of you technical boffins can help me out of this pickle

I've just changed the front brake disks on my wife's Rav4 (a job I have done several times before on various cars over the years)

Bled the system (with engine off) and the resevoir is at correct level

The brake pedal is nice & firm (as it should be) until the engine starts running

Then, brakes become incredibly spongy and I'm sure wouldn't stop me properly at speed

There is no sign of air anywhere or leaks

Can you help me? am I missing something blatently obvious?

Car is off the road now and 'her who must be obeyed' is really chuffed that she will have to walk the kids the 2 miles to school tomorrow

 

You say you have changed the disks ! Did you change the pad as well?

and more to the point why did you bleed the system?

 

Radiotwo

[Bubbles]

Firstly thanks for your responses

I didn't change the disks, it was the pads (excuse me - I'm a plonker)

The car isn't new its 1996

I forced the pistons back to accomodate the new pads (they went in no problem)

I only bled the system as I had inadvertantly loosened the pipeline bolt (attached to the calliper) in my haste to get the job done (like I said - plonker)

There was only the slightest trickle of fluid but I thought it best to bleed the system as some air may have got in

Following my post last night - I can hear the sound of air escaping from near the resevoir (as if the lid isn't air tight) - should this hold pressure?

Also, a friend has suggested that the symptoms of spongy brakes (following new pads) isn't unusuall and it could take some miles to bed in. However, I can hit the floor before the brakes really bite on and if I pump the pedal, the symtoms get worse

I really appreciate the advice - Thanks

PS - The wife has got the Galaxy and I was made to use the bus service (lost out there too!)

[seatkid]

I know this isn't stricky Galaxy related

Correct! And I hope you dont make a habit of soiling this forum! :D

 

The answer to your problem - change your disks as well - they are worn out.

[Bubbles]

Thanks

I'll try that