Why do I have no brakes *Update*

[Danny2009]

As title driving along fine brake foot goes to floor and I'm not stopping press them again fine

Turn car off pump brakes keep foot on brakes start car up pedal Dosent move

Foot off brakes rev car press brakes straight to floor again

Any ideas?

309 1.8 xud

[Toms306]

Sounds like a servo issue to me tbh. Could be a split vac pipe to it possibly?

[Seb_Ryan]

Yeah sounds like lack of servo..

[Curt]

Sounds like the vacuum pump is playing silly buggers to me if it changes with revs

[Danny2009]

I thought it was vac pump / piping if it was servo it would stay firm or soft not change?

Left it 3 hours just come to it to drive home I now have normal brakes

Dafuck?

[Curt]

Just thought about it again. If it was a vac/servo issue, the pedal would go firm and you would have reduced braking due to the lack of assistance... It's usually when you have air in the system or a leak it would go to the floor. Doesn't make sense why it'd be intermittent either.

[Danny2009]

Hit the floor felt the pedal hit the metal but if I pump it they worked

Turned it off pumped them solid kept my foot down didn't budge when started

Gave it a rev and they hit floor again

Left it about 3 hours probably more and it's fine now not done it once

[Rippthrough]

If it's going to the floor like that there's a dicky seal somewhere, or air has got in somehow, that's not the servo.

[Danny2009]

Can't see it being air in the fluid as it's fine now?

I'll have a route round tomorrow baffling

[Rippthrough]

Could be a seal that's lost it's edge and not expanding properly, master cylinder itself is the usual culprit for that one.

[Danny2009]

The actual master cylinder or the seal between that and servo

[Rippthrough]

The master cylinder. Loosing the servo vacuum wouldn't make the pedal go to the floor, it'd just mean you had to give the pedal a proper shove to get the car to stop. Check all the fittings and lines first to make sure there's not a weep around a thread or a pinhole in a line though.

[Danny2009]

Your the brake man can I make a 2 port mc work on a 4 port car?

I have a 2 port 6 mc laying about that's all

[powerandtorque]

You can with a couple of T-pieces and a bit of tweeking of the lines, but personally I wouldn't use old MC's that have been sitting around with no fluid for any length of time.

Whilst it would work a GTi-6 MC will be a bit big if you're running standard 309 calipers too, but will be alright if you're running bigger front calipers.

A new Bendix 205/309 MC isn't a lot of money and will last many years. Beware of cheap pattern s**t.

[Danny2009]

I want a 6 mc as I'm fitting bigger brakes soon

[powerandtorque]

Another option is an early 406 non-ABS MC - these are 23mm 4 port and a direct fit onto a 205/309.

[Danny2009]

Cheers mate

[Rippthrough]

Yeah, that's the unit I have on mine.

[Danny2009]

I've recently fitted gti6 brakes and the fluid looked like engine oil it was so black so put fresh in

All been good up to tonight

Had 2 mates in the car one in the front one in the back

Going over wood head/snakes pass brakes was ok

Been to pick a axle up put that in the back get down the road I have no brakes

Foot goes to the floor and not actually slowing down

When going over dips in the road can feel the car like brake on its own like there is someone pulling the hand break a little

Also feels like rear brakes are binding/on

Dropped my mate and the axle off so there's me and a front seat passanger now there fine

When it happened the first time when I made the thread I had a set of wheels and a load of other shite in the car

So it only happens when I have weight in it seems

Load sensor valve f*cked?

[firemoth]

The load sensor shouldn't stop you braking, it might limit the rear brakes but it won't affect front. If the fluid is black, have you given it a complete flush through?

[Danny2009]

Yea mate kept bleeding it till the master cylinder was full of clean fluid and clean fluid came out of bleed nipples

[Toms306]

As above, the load sensor is only for the rears, to stop them locking when theres no load in the rear mainly. Shouldn't affect the front tbh. However (I'm not 100% on how it works, but I think this is right!) there could be air in the load valve, so its fine normally, but stick weight in and then when its 'open' you're just compressing air.... Try bleeding them with some load in the back imo...

[Danny2009]

Or Take the ducker off

I'll give that a go tom

[powerandtorque]

There isn't a load based brake compensator on a 309 like there are on 106, 306's etc, with the exception of rare ABS models (and they have one per side, not a combined one like the x06 models).

If the GTi rear brakes have been fitted as per a 309 GTi then it'll have a pair of inline compensators.

Best guess for the dragging feeling on bumps when you've a lot of weight in the back is that the handbrake cables are too tight and pulling on the bumps when the back is sitting low from the weight. The route of them on 205's and 309's means that they tighten slightly as the arm moves upwards.

You shouldn't lose the brakes completely because of that though, although the rears will overheat eventually from the dragging.

[Toms306]

I'd forgotten this wasn't a 306!

[firemoth]

Or Take the ducker off

I'll give that a go tom

That's what I'm doing with my 405. Should be finished on Saturday, I'll let you know the results

[pugmanxud]

Master cyl seals