fecking brakes
Turbo Mini Forums

Can anyone shed any light on my brake problem please?

I've just changed from the satandard 91 servo/master cylinder combi thing, over to non servo brakes to give me a little more room in the engine bay. and at the same time i've fitted a pair of metro 4 pots and 7.9" vented disks so i can run on 10's.

Trouble is now i cant get any pressure at all in the brake pedal, me and kean(T2clubby) have spent all of today bleeding them, checking the calliper pistons move, checking the rears are adjusted etc. but still no pedal at all!

The only thing we can think of is that the master cylinder i'm using doesn't move enough fluid. however Doodmeister is using the same master cylinder as me with his 4 pots and his are fine, so we're fecking confused!

Cheers, Nick.

What I can think of: Metro 4 pots have pretty big pistons, so you could be right on the "not moving enought fluid", But I just had a chat with a guy down the road who's on 12"s and metro 4 pots (didnt thinkyou could get them under 10's,...now I know better) and no servo - and they're fine, plenty of pressure.
I run a set of billet 4 pots, no probs here now, but enough getting them set up and bedded in.

Two things:
1: Master Cylinder seals are shot - you could bleed it all day, but still would blow by. Do they "pump up"?
2: Brake flexis are ballooning - can happen if they've been crushed/nicked when being put on - I had a set of older, but still good looking hoses go on me on the rear subframe, and took me two days to find the buggers.
3: Rear pistons are shot and peeing fluid into the drums so you cant see them. Friend of mine had all sorts of fun with this one.
4: ... working on this.

Hope this is ok!

are the calipers on the right sides, if theyre upside down, makes them imposible to bleed, heard of that one before

Phil

1. I'm thinking it could be the master cylinder, but seeing as its £95 for a brand new one i want to eliminate everything else first.
2. Haven't checked the rear flexi's, got braided on the front, but i'll check the rear's tomorrow night when i check on the rear cylinders, i'm not losing any fluid and they're only about 6 months old but gonna check anyway!
3. as above.

the callipers are on the right sides, first thing i made sure of, bleed nipples at the top and in the middle.

my 4 pots have been machined to fit under 10's, the discs are turned down to 7.9" and the calliper bolts holes are slotted to move the whole calliper closer to the centre of the disc, and the back of the of the wheel studs are ground down a little to clear the callipers as they're closer now.

I've been and had a look at my moms car as she's also running 4 pots, however her master cylinder is different to mine, it looks a lot bigger from the outside so i'm assuming the bore is bigger aswell, as her pedal was really good when i took her car on the riv run earlier in the year.

The only other thing i can think of now is the bias valve thing on the bulkhead that could be fucked, but i thought these leaked when they were knackered.

Thanks for the advice dudes,

Nick.

Hi

Get an old bit of brake pipe and bend it over so no fluid can go through it and put it in the top of the master cylinder. Brake pedal should now be solid. If its not the seals are duff. Thats how I checked mine cos I had the same problem. Turned out I just wasnt beading them correctly. I use metro 4 pots with standar master cylinder no problems.

Colas

that seems like a better idea than putting me finger over the holes :)

I'm gonna pick up an ezbleed kit today, might aswell give bleeding em another try.

right, been busy tonight again.

Used an ezbleed kit, fuck knows how i ever managed without one they're really good! but still no air came out at all just nice clean fluid.

Ive got no leaks anywhere, the rear flexi's look fine and aren't expanding or anything.

All i can see are 3 options now.

1, try a different master cylinder again.
2, change that bias thing on the bulkhead just incase its fucked
3, put me old 8.4" setup back on and see if its any better. which i dont wanna do cos i really wanna fit me new 10's :)

Nick.

Edited by Nick on 18th Oct, 2004.

I'm afraid it relly does sound like the master cylinder.... Just a dumb question - is it plumbed in right? I know if you have dual line brakes they can be a pain.
Just my 2pence worth.

yeah it is, it wasn't at first until i looked at a photo of doodmeisters setup. but its still the same after that.

Hopefully ians got a cylinder for me, and i'm winning billydudes on ebay aswell :)

did you like the packing of the pedals ?Lol

is your regulator thing on the right way ?
as this is supposed to cause trouble when bleeding if its upside down

heres how the pipes should be

top to the nut side
the mounting bolt on the regulator should be at the top

Edited by billydude on 18th Oct, 2004.

lol. i was gonna have a game of pass the parcel with em :)

yeah the reg thing on the bulkhead, has never been moved. still it might just be fucked though.

I don't know how often those regulaors go
but I blew the end off of one with that master cylinder

cool! at least it can get some pressure up then!

Lol I'd guess so
luckily it popped of outside my local scrap yard who had one mini in and I knobbled it's regulator and fitted it before driveing home

I'm back thank feck
damn I'm not doing that again
Rain sheesh someone stole the A5 and replaced it with a canal

wish someone would steal the A5, god damn road
And the M6 while there at it

Lol I was doing 70 then all of a sudden it rained heavily and the left hand lane was just a big puddle
and my wipers can't cope with that kind of rain Lol
but considering the amount of rain I went through not a single missfire or splutter
I dread to think how deep it was but all I could see was water

Well the brakes have got a little better now, still it seems like the fronts aren't doing a fecking thing though!

I've swapped over to the master cylinder and bias valve i had off billydude, and im using his pedal box aswell, so everything should all work together in my car if it has in his! right?

Anyone got any ideas at all what it could be?

I took it round the block earlier and it only feels like the back brakes are working, i've got some pressure in the pedal now but only after about 3/4 of the way down, then you can still get it to the floor if you really push on it.

Nick.

oh yeah, ive put my old 8.4" setup back on aswell to try and rule out the new 4 pots.

it sounds like you're not having much luck with brakes !
i hope my four pots dont give me these problems!
DAN :)

they're really doing me head in now. i just cant see what else it could be!

how have you been bleeding them ?
I find gravity works the best

we've been using an ezbleed aswell as the old 2 man method. might give that gravity idea a try though, is that when you just open up all the nipples and keep the master topped up?

yup
I do the rears then the passenger front and the drivers front last
and I get stomping brakes first time every time so far :)

hmmmm. might aswell give it a try then. i got no other idea's.