Brake Pedal Soft
Brake Pedal Soft
Author
Discussion

swimmer27

Original Poster:

482 posts

211 months

Monday 6th December 2010
quotequote all
Hello all,

It's been some time since my last post due to personal reasons.
My S2 passed it's MOT in July and has not been used for the last 3 months. It fired up first go so drove it out of my garage only to find the brake pedal as soft as a sponge.
I removed the rear drums and all looks fine with the rear wheel cylinders as do the front calipers so then bled the brakes but still the pedal is soft whilst the engine is running.

I then decided to remove the brake master cylinder to see if there is any evidence of leakage but here's my problem, the higher of the two retaing nuts holding the cylinder to the servo undid but the lower nut keeps turning with the stud.
I have a Dremell tool so would cutting the nut off the stud be an option or does anyone have any other ideas?

Mine is a 1989 model and has the seperate brake fluid reservoir so not the Sierra type.

Right next to the master cylinder is a small metal reservoir with brake fluid too.

I think the servo is ok as can't hear any leakes but there is some rust I can feel at the bottom of the unit.

Thank you all

Paul



Edited by swimmer27 on Monday 6th December 21:04

Gerald-TVR

4,896 posts

226 months

Monday 6th December 2010
quotequote all
swimmer27 said:
but the lower nut keeps turning with the stud.
Is there enough thread to add two lock (thin) nuts together? And then at least start the nut moving?

Otherwise I have an OLD servo bodged up with fibre glass which you can try BUT ITS NOT SAFE to use on the road, you are welcome to have it as a test thing but then it should be broken up.

swimmer27

Original Poster:

482 posts

211 months

Tuesday 7th December 2010
quotequote all
Thank you for the reply, there is not enough room for two thin nuts only one so I will have a go at cotting it off of purchase a nut splitter. Thanks for the offer of the servo but im sure it's the master cylinder.
Regards

Paul

Donnysoutherner

301 posts

201 months

Wednesday 8th December 2010
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Hi, suggest that if the pedal is soft when engine running and hard when not running the servo probably IS working. This is because the servo is applying greater pressure to the pedal, hence any air in the lines will show greater compression. I had the same trouble, it was perseverence and a friendly mechanic who was better / more than me that eventually got th brakes harder.

swimmer27

Original Poster:

482 posts

211 months

Tuesday 21st December 2010
quotequote all
All sorted, finally got around to bleeding the brakes so the pedal is back to normal.