Brake Pedal Going Straight To The Floor

[gti-si 0]

Need your help Guys!

 

I'm trying to get my 205 back on the road but having major problems with the brakes. I've put some Austin princess 4pots on the front, not to my taste but all I have at moment. Now I've bled the whole system and the pedal was very very soft with the engine off and no vacuum. I rebled and it was the same, checked for leaks in the system and found none, no wet spots or signs of leaking brake fluid anywhere on the car.

 

I then decided it must then be the master cylinder seals giving way, so off I pop down to GSF and purchase a brand new master cylinder...on it goes, rebled and hey presto, it's exactly the same.

 

Really running out of suggestions, anyone ideas? Really need to get this sorted tonight or tomorrow..

 

If it was the calipers seized, I would expect a solid pedal and if the caliper seals had gone I'd expect to see brake fluid pissing/dripping out but there dry as a bone.

 

Have done a search but it didn't come up trumps

[GLPoomobile 958]

Well good old Haynes says it has it be either a fluid leak or the MC seals not holding pressure. Duff replacement MC maybe I know a few people have said recently to be careful of what type MC you get from GSF and I know one member had a duff one he had to return.

[gti-si 0]

Hmmm, I'd looked at that Steve, that's what got me so stupmed! I did make sure it was a Bendix MC if that helps? Anyone had a duff one of these?

 

Anyway the rear compensator can give any symptoms like this? I can't see how it would but you never know, best to ask and all!

 

Could it be anything to do with the 4 pot's needing a bigger MC or anything?

[AdamP 0]

The 4 pots take a hell of a lot of fluid to displace them! I'm guessing you probably need a bigger M/C.

[gti-si 0]

I thought of that, but surely it wouldn't account for a sloppy pedal? As long as there's no air in the system, it should still fill up the bores in the calipers, just require a lot of pedal travel to engage them fully, this isn't the case, there's no braking power at the front what so ever..it's very weird.

 

Is it something I'm doing wrong bleeding them? There are three nipples on each caliper, one on the top and two slap in the in middle of the pistons on each side. Any special conditions applied to bleeding them? Airlock in the caliper?