After my little knock into a fence post the other week at henstridge, I've noticed that now and again my brake pedal travels all the way to the floor when I'm stationary, still has reasonable reistance, but I am able to depress it fully.

Also on occasions, when normal braking, I get a little crunch under the pedal like the abs has kicked in.

I'm unsure if its all related to the fence incident but has started since then so I presume so.
Brake fluid is level so just wondering if anyone would know what could be causing this as I'm illequipt on knowledge off the st185 braking system.

Jon

_________________
1998 ford st24, 186hp 2.5 v6- sold
1997 bmw e36 318ti, mint hellrot red- sold
1992 celica gt4 st185- td04 340hp/330lbs
1998 mercedes E280- sold
1998 pug 1.9 td- mile muncher!
1993 rx7 542hp savage monster!!
2007 BMW 335i- in the shop gettin built!!

ABS problem sounds a bit like phil had on his 205. I'd suspect a problem with the G sensor. Having never dealt with ABS, I'm afraid I have no clue where it's located.

Re. foot to the floor, does it only happen when staionary, and does it require more force than you would normally use for braking ? i.e. is it just a very spongy pedal.

_________________
If at first you don't suck seed, try drier grain.

Yes does require more force, only tried it due to the clicky knock of pedal from abs.

Just heard what sounded like a motor when braking to a stop from about 20mph and felt the pedal drop and kind of click too.

_________________
1998 ford st24, 186hp 2.5 v6- sold
1997 bmw e36 318ti, mint hellrot red- sold
1992 celica gt4 st185- td04 340hp/330lbs
1998 mercedes E280- sold
1998 pug 1.9 td- mile muncher!
1993 rx7 542hp savage monster!!
2007 BMW 335i- in the shop gettin built!!

Pull the abs fuse and make sure the problem goes away

Where is abs fuse?

_________________
1998 ford st24, 186hp 2.5 v6- sold
1997 bmw e36 318ti, mint hellrot red- sold
1992 celica gt4 st185- td04 340hp/330lbs
1998 mercedes E280- sold
1998 pug 1.9 td- mile muncher!
1993 rx7 542hp savage monster!!
2007 BMW 335i- in the shop gettin built!!

From the wiring diagram it's in the main fuse box in the engine bay (next to the battery normally)

_________________
If at first you don't suck seed, try drier grain.

Hiya

If your brake pedal travels to the floor but still has resistance then you have either air in the system, a hydraulic leak or seals in the master cylinder are worn allowing fluid to pass, I would be surprised if its a leak as you say your level is ok

The noise on the brake pedal does sound like abs engaging, try pulling the fuse as others have mentioned but from past experience this is caused by a snapped exciter ring on the driveshaft, ive seen this many times in a gt4

Hope it helps

Martin

_________________
We now have a new website

https://www.mkautorepairsandtuning.uk/

http://www.facebook.com/pages/Mk-Auto-R ... 7894641634

Ok thanks, sounds complicated. I'll try the fuse first if I can find the correct one and if it doesn't work ill leave it just now as ive noticed it only happens once after starting car up then its fine other than abs light comes on.

_________________
1998 ford st24, 186hp 2.5 v6- sold
1997 bmw e36 318ti, mint hellrot red- sold
1992 celica gt4 st185- td04 340hp/330lbs
1998 mercedes E280- sold
1998 pug 1.9 td- mile muncher!
1993 rx7 542hp savage monster!!
2007 BMW 335i- in the shop gettin built!!

I was talking about this in the cc and the problem i have with the ST205 isnt that its spongy just delayed as in the pedel has to travel a bid down before anything happens.

The brakes are working fine, just I can depress the pedal fully down at a standstill.

_________________
1998 ford st24, 186hp 2.5 v6- sold
1997 bmw e36 318ti, mint hellrot red- sold
1992 celica gt4 st185- td04 340hp/330lbs
1998 mercedes E280- sold
1998 pug 1.9 td- mile muncher!
1993 rx7 542hp savage monster!!
2007 BMW 335i- in the shop gettin built!!

I can on both mine too Jon. One with and one without ABS

A test for seal issues - press the pedal firmly and hold constant pressure. If the pedal creeps down then there's a blown seal somewhere. It's not a guaranteed test but it will often show issues

Ray,
You are right. There is some slack in the system but it should not be that excessive. A good test -
With the car stationary test the pedal free travel. Repeat with the car moving. If the travel feels different between the two tests you have play in something somewhere - either wheel bearing or disk runout

Re the current CCUK thread where I can't post
You are correct that I only measured a 2mm flex in the servo which doesn't seem much. But there is a significant multiplication in that flex at that brake pedal because of the lever effect in the pedal box. So if the ratio is say 5 between pedal movement and master cylinder piston movement a 2mm flex will move the pedal 10mm

Ok so after removing abs fuse the brakes are no longer shuddering. So its a tempory fix that I shall live with for now.
Is it possible to remove abs system completely without to much fuss?

_________________
1998 ford st24, 186hp 2.5 v6- sold
1997 bmw e36 318ti, mint hellrot red- sold
1992 celica gt4 st185- td04 340hp/330lbs
1998 mercedes E280- sold
1998 pug 1.9 td- mile muncher!
1993 rx7 542hp savage monster!!
2007 BMW 335i- in the shop gettin built!!

I believe you will fail your MOT if you do this.

_________________
ST205

You would need to remove all abs components, particularly the pump. [qoute]If it's fitted it must work[/quote]

We have done this on a couple of cars, in both cases while the engine is out as it's very difficult to get to the pipework with the engine in place.

_________________
If at first you don't suck seed, try drier grain.

so if I stop the BMC from moving by 2mm then the slack of 10mm by the pedal should reduce rite?