Mushy brake pedal after dropping the tranny

[BigBadBen]

Hi Loren,

Have you any idea why I would get a totally mushy brake pedal after I drop the tranny on my car, it makes no sense at all as the two systems are totally seperate. This is so odd.

I had an issues with the custom triple **** clutch setup that I have, so had to drop the tranny...no problem. Put everything back together tonight and basically the brake pedal goes pretty much right to the floor, pump it a bit and it gets a bit hard and then goes soft again. We did NOT touch the brake system in anyway. No fluid leaks...nothing.

The only solution I have found is to bleed the system completely, no bubbles come out and all seems good again....I will be bleeding the system on Tuesday but it's just a pain in the bum! BTW I am using Castrol SRF fluid and a Motive Power Bleeder.

I am totally perplexed by this. This also happen when I recenly changed my pads...again I did not brake any of the lines but I had a very soft, mushy pedal again.

Does this sound like a dodgey master cylinder?

Cheers,

Ben

[Loren]

You are correct that on a TT the clutch and brake system are completely separate and even use different fluids. One should not effect the other.

If bleeding or pumping the brakes does not improve the pedal feel then the problem is likely pad taper or the pads were overheated or the pads were not bedded in properly.

Usually when it is a bad master cylinder you can detect bleed down when holding the brake pedal down.

Has the car been driven since the brake pad and fluid change? and were the two done together at the same time?

Was the ABS/PSM system also bled?

[BigBadBen]

Sorry for the late reply, my internet has been down for the past 48 hours due to Major T-storms. Well I decided to totally flush the brake system and start from scratch. I ended up using Audi DOT 4 fluid that is used in the RS series cars..there is no decent place in my town to pick up good fluid anyway.

I used close to 3 x 12 fl oz bottles and throughly flushed things out. The pedal is like a rock now, its never been like that before. A few months ago I did install Pagid Oranges all round and followed the bed in to the letter per the Pagid site...but still even then the pedal feel was not like it is now.

I have never bled the ABS/PSM system, I assumed it was all one and the same. I am still very perplexed by this, as none of it makes sense to me.

All is perfect now so hopefully I won't have this issue again, I would just like to figure out why..these sort of things bug me til I find out what is wrong.

Thanks for the advice Loren..as always you are a great help. :cheers:

Cheers,

Ben

You are correct that on a TT the clutch and brake system are completely separate and even use different fluids. One should not effect the other.

If bleeding or pumping the brakes does not improve the pedal feel then the problem is likely pad taper or the pads were overheated or the pads were not bedded in properly.

Usually when it is a bad master cylinder you can detect bleed down when holding the brake pedal down.

Has the car been driven since the brake pad and fluid change? and were the two done together at the same time?

Was the ABS/PSM system also bled?