brake problems i give up now!!!

[steve_k]

Well seeing as I'm running an e90 servo I had a look on realoem/bmwfans.info & I can't see a check/non return valve on either of the diagrams, yet I've got one fitted,

So I'm thinking of taking it out & trying a simple barbed connector instead.

I also noticed that the calipers were missing the R clips (pad retaining clips), so I'm sure that won't be helping,

Got so.e now so I'll fit them when I get back & try again.

[flybynite]

Couple of things

Keep trying it, if the pedal is going soft, keep pushing it for a while. If it is due to a leak push enough fluid through it to see. You can get fluorescent dye for that purpose (unless that is something else that has been banned) Keep a REALLY close eye on the fluid level.

You only need a slight weep to cause a soft pedal, there is not going to be a lot of fluid. I had a bitch of a time with a bad bleeder not sealing when tight. Soft pedal but not much fluid at all, barely enough to see creeping past the threads. Only fixed when I replaced cheap shite ebay one with one from a proper brake place

Second, disconnect the vacuum line completely and test the car. How do the brakes work. Yes they will be hard to press but do they stop the car and hold pressure?

As Stones says above, failed braided hose, won't leak and difficult to spot

Finally remind me exactly what the problem is as it stands now. Is the pedal soft or does it go all the way to the floor. Can you push the pedal down with no vacuum assistance? It will be a lot slower but you will push them down if it is a leak.

[steve_k]

Couple of things

Keep trying it, if the pedal is going soft, keep pushing it for a while. If it is due to a leak push enough fluid through it to see. You can get fluorescent dye for that purpose (unless that is something else that has been banned) Keep a REALLY close eye on the fluid level.

You only need a slight weep to cause a soft pedal, there is not going to be a lot of fluid. I had a bitch of a time with a bad bleeder not sealing when tight. Soft pedal but not much fluid at all, barely enough to see creeping past the threads. Only fixed when I replaced cheap shite ebay one with one from a proper brake place

Second, disconnect the vacuum line completely and test the car. How do the brakes work. Yes they will be hard to press but do they stop the car and hold pressure?

As Stones says above, failed braided hose, won't leak and difficult to spot

Finally remind me exactly what the problem is as it stands now. Is the pedal soft or does it go all the way to the floor. Can you push the pedal down with no vacuum assistance? It will be a lot slower but you will push them down if it is a leak.

Thanks for that buddy,

Good shout on the bleeder not sealing properly, I'll pull them out & wrap them in ptfe tape & try them again, thing is they weren't cheap as I got them from hi-spec brakes & are S/S,

I'll male sure all the bleeders & unions are right & dry & wrap them in bog roll before I try again, at least I'll see if there is a leak (no matter how small),

As for disconnecting the vacuum line? That's now on the list to be tried.

Also I have removed the line that was kinked I borrowed a vacuum bleeder & couldn't see any leaks it it at all.

The original problem was the pedal being firm with the engine off & soft went I went to use the brakes on the drive at (very) low speed (under 10mph),

Plenty there to be going on with so watch this space.

[steve_k]

Ot might take me a few days to try the above as I work as a carer for both my dad round the corner & for my son 70 miless away so I can only do it when I gey chance.

Don't worry I am trying g everything suggested.

[steve_k]

well i still appear to be having problems with these brakes.

over the past week i have rebuilt the front 4 piston calipers with new seals, dust boots, pistons & stainless steel bleed nipples,

bench bled the M/C, stripped & rebuilt the rear calipers (even though they were brand new late last year) replaced all the unions with new (stainless steel) ones, flushed out all the brake lines front to rear,

replaced the rubber grommets under the revivor in case they were letting air in,

replaced the non return/check valve on the servo with a new one & replaced the vacuum line with a new (silicone) one.

bled the system more times than i care to think about (put about 3.5L of dot 5.1 fluid though it).

once i'd done all that, pumped the pedal loads of times & checked for any leaks, glad to say all the unions are bone dry so no leaks.

now, with the engine off if i press the pedal it will go down a little bit but will not go rock hard as you would expect,
with the engine running the pedal will go down about half way & no further but it seems to make the engine hunt slightly which makes me think there could be a vacuum leak some where.

i really am at a loss as what to do now, i've gone through the whole braking system with a fine tooth combe & can't find anything that could be causing the problem.

i'm so close to giving up as i really dont know what else to try.

if i get chance in the next few days i'll drop the car off the stands & move t back & forth on the drive & see if there is any improvement in the brakes then.

if i've missed anything then please post up,i am desperate to get this car on the road as it's been an ongoing project for the last 10yr's & i just want to drive it again.

[steve_k]

time for another small but significant update.

over te past 2 days i've bleed the brake a further 3 times (got it down to sub 10 mins now) & dropped the car to the floor today to test them,

moved the car back & forth a few times & noticed all of a sudden that the brakes went very soft & i had to use the handbrake to stop fully.

got out & saw a large patch of fluid on the floor near the rear drivers side wheel, so, got the car back up on the stands, removed the rear wheel to see fluid dripping quickly from the caliper.

had a good look & it turned out to be coming from the 90 degree m10 male union from the braided steel line to the caliper,

one of these https://www.carbuilder.com/uk/90-degree ... at-m10-x-1

turns out it had a nice 1/4" split/crack along the little pipe, so no wonder i lost the brakes,

been ringing around anywhere local to me that might have one in stock but no luck.

just ordered two from car builder solutions & hopefully it's here pretty quickly & i can replace both sides just to be on the safe side.

i really hope this could be the end of my problems with the brakes.

[martauto]

It can only help the situation mate
Dont you dare give up on this now Steve, you have to be soooooooooo close to the end result.

Take the positives out of this........................you can set up a company bleeding brakes!!!

Mart.

[steve_k]

It can only help the situation mate
Dont you dare give up on this now Steve, you have to be soooooooooo close to the end result.

Take the positives out of this........................you can set up a company bleeding brakes!!!

Mart.

Don't worry mart I ain't giving up, I've come to far,

I'd never built an engine when I first started this build nearly 10yrs ago & now I've rebuilt it as a high spec stroker, Rebuilt & upgraded the gearbox, diff, suspension & nearly all of the car.

So I doubt I'm going to let a split union alerte throw in the towel,

As for starting a business? Is there much call for F1 pit stop quick brake bleeding??

[martauto]

I have all four calipers and hose`s to replace on the E46 (just being VERY anal) so I may just ask for your advise ?

Your commitment was never an issue mate

Anew thread is in order.

Mart.

[steve_k]

I have all four calipers and hose`s to replace on the E46 (just being VERY anal) so I may just ask for your advise ?

Your commitment was never an issue mate

Anew thread is in order.

Mart.

Nah you don't want advise from me even I don't trust my own advise

Hopefully when it's back on the road there'll be a thread with a load of pics of it put & about.

[martauto]

I have just started two about bleeding and new pipes so I think you will have a loooooooad to ad mate

Mart.

[steve_k]

I have just started two about bleeding and new pipes so I think you will have a loooooooad to ad mate

Mart.

i'll have a look.

[flybynite]

had a good look & it turned out to be coming from the 90 degree m10 male union from the braided steel line to the caliper,

Had a feeling it would be something like this, Like I said with me last time it was a bad seating bleeder, surprising how it affects the pedal.

I have learned to give the caliper a squirt of brake cleaner after bleeding to get all the fluid off and dry it really well. Then go round it afterwards to spot leaks.

Hopefully that will sort it now, well done for sticking with it

[steve_k]

had a good look & it turned out to be coming from the 90 degree m10 male union from the braided steel line to the caliper,

Had a feeling it would be something like this, Like I said with me last time it was a bad seating bleeder, surprising how it affects the pedal.

I have learned to give the caliper a squirt of brake cleaner after bleeding to get all the fluid off and dry it really well. Then go round it afterwards to spot leaks.

Hopefully that will sort it now, well done for sticking with it

Thanks buddy,

I've gone round the whole lot with brake cleaner before,

Also found out I want meant to reuse the copper washers on the front 4 pots so going to get some new o es either Monday or Tuesday,

Hopefully by the end of the week it's all sorted.

As for sticking with it? I've spent far far too much over the last 10yrs to give up now.

[DanThe]

This is the exact reason why I wont use anything other than Goodridge components for brakes, I certainly wouldnt be buying more of the same part that has failed...

Imagine that splitting when you are trying to avoid an accident at speed and giving the pedal the biggest press its ever had

[steve_k]

This is the exact reason why I wont use anything other than Goodridge components for brakes, I certainly wouldnt be buying more of the same part that has failed...

Imagine that splitting when you are trying to avoid an accident at speed and giving the pedal the biggest press its ever had

i fully agree dan,

after talking to my father in law (who built & races his own mk1 golf rally car) last night he said the same thing & told me to use goodridge & i've now ordered these \/\/\/\/\/\/\/\/ as he uses them on his rally car.

https://www.goodridge.co.uk/collections ... 4946241159

expensive, yes, bt what price safety & peace of mind?

[flybynite]

This is the exact reason why I wont use anything other than Goodridge components for brakes, I certainly wouldnt be buying more of the same part that has failed...
Imagine that splitting when you are trying to avoid an accident at speed and giving the pedal the biggest press its ever had

The trouble I find is that sh*t materials are also making their way into brands I have used for years, even when bought from reputable places. Could be fakes getting in there but same result.

Paying top money doesn't guarantee anything either.

Just had a day of self-tappers made of cheese and pop rivets made of chocolate, fine if you have missed lunch but no use for much else

[steve_k]

well the new unions for the rear brakes will be here today so i'll crack on with them if it stops raining long enough,

also, this could be something or nothing, but i'm begining to wonder if i've got the banjo bolts on the front calipers the right way,

what i mean is, do i have the channel in the banjo itself lined up correctly with the channel in the bolt,
i guess it can't hurt to check can it?

[steve_k]

well the new unions have arrived (good ole royal snail) so soon as it stops raining i'll be off out to et them fitted along with some thicker (1.5mm) copper washers for the front banjo bolts.

all good fun.

[martauto]

well the new unions have arrived (good ole royal snail) so soon as it stops raining i'll be off out to et them fitted along with some thicker (1.5mm) copper washers for the front banjo bolts.

all good fun.

Still crossed mate

Mart.

[steve_k]

well the new unions have arrived (good ole royal snail) so soon as it stops raining i'll be off out to et them fitted along with some thicker (1.5mm) copper washers for the front banjo bolts.

all good fun.

Still crossed mate

Mart.

thanks mart.

well got them all fitted, refilled the system, used the pressure bleeder & bled the system, couldn't see or find any leaks anywhere, all the unions were nice & dry,

pedal was firming up nicely,

check for leaks again but found none.

then used the vizibleed bleeder & pumped the pedal myself, again no leaks pedal firming up.

i was going to bleed it again to make sure all the air was out the system but i ran out of fluid, so i'll get some more in the morning bleed it again then drop the car down & try the breaks.

[martauto]

Dare I start to believe ???

Sounds very promising Steve.

Mart.

[steve_k]

Sorry for the late reply had a few family problems to deal with.

Well I'm still stuck with the same problem.

In the oast week I've stripped the lines & had them checked & the unions redone by a local bike spares shop that makes up braided steel brake lines for motorbikes, he said they were absolutely fine with no leaks,

Bench bled the master cylinder again to make sure there was no air pockets trapped inside.

Bled the whole system again, used some brake fluid dye when I flushed it all through with new fluid, wrapped all the unions in bog roll when I flused the lines to see if there were any leaks, none found.

Checked the servo over, no problems there, fitted a new one way valve,

Adjusted the brake pedal to the correct height,

Now I'm starting to think the passenger side caliper could be sticking as the wheel can be hard to turn by hand, even though it was rebuilt about 6 - 7yrs ago, as I'm starting to think there could be a problem with the internal seals.

I know I could rebuild it again or simply buy a replacement but that's nearly £200 I could do without spending but at least I would then know there's 4 new calipers on the car instead of 3 (rears & front drivers side were replaced last year).

Looks like I'll have to get a new caliper from hi-spec, fingers crossed that sorts it,

I'm so close to giving up as it's really taking it toll on me now.

I honestly don't know what else it could be that's causing a soft pedal.

[steve_k]

Just an idea, to find out if the passenger side caliper is seized ill take it off & try to push the pistons out with the compressor & see if they come out easy or hard.

The reason being is that when I came to bleed the brakes the inner passenger side was hard to get any air out,

When I pressed the pedal it was a lot lot stiffer then the other calipers,

Makes me wonder if the inner pistons have started to seize.

[steve_k]

well today i'll try to find out if i can simply rebuild the front passenger side caliper (new seals, pistons & dust boots) or if i ill need a new caliper.

hopefully it's the former.

[steve_k]

well i've had a good look & it would appear that i now have a choice to make.

took the caliper off, pushed the pistons back in & then put 100 - 150psi through the caliper to push the pistons back out to find that the 2 on the outer side of the caliper were stuck in the bore.

tried this a few more times & had the same result each time,

so now the decision is whether to but a rebuilt kit ( 4x new pistons, 4x seals & dust boots) or simply buy a replacement caliper from hi-spec.

decisions decisions.

[martauto]

If you go for the re-build job then you are still left with the original bores and maybe they have scored slightly.
You can rub them smooth but you are left with the same situation as before and putting new seals in will only delay what happened before.
Would you put new rings in your engine with scoring in the bores without a re-bore??

Mart.

[steve_k]

If you go for the re-build job then you are still left with the original bores and maybe they have scored slightly.
You can rub them smooth but you are left with the same situation as before and putting new seals in will only delay what happened before.
Would you put new rings in your engine with scoring in the bores without a re-bore??

Mart.

i know what you mean mart but the problem i'm stuck with is the fact that when i replaced the drivers side caliper last year i ordered it through gsm performance, mainly because they were a good few quid cheaper than hi-spec themselves, turns out they were cheaper because it took them nearly 3 months to get the caliper to me.

thats the reason i was thinking of a rebuild to start with, also i've found out that the pistons from a brembo 4 pot caliper as the same size & shape as the hi-spec ones.

i'm waiting to hear from hi-spec on the lead time/availability of the caliper i need, can't really decide what to do till i've heard from them,

plus i don't fancy waiting nearly 3 months again.

[TriggerFish]

Assuming a rebuild kit is cheap enough, could you not rebuild to get it back on the road for now, and then replace in 3 months when the caliper turns up?

Fingers crossed this is the final piece of the puzzle though!

[steve_k]

Well I've been in touch with hi-spec today about a replacement caliper & they said yes they could do it but it could take upto or beyond 3 months for it to get to me as they have closed their books due to high demand.

Well I've been looking on the zone FB page & there was a post about using mk3 mondeo front calipers & brackets & audi a3 1.8t 280x25 front discs with the pcd changed to 4x100, well just had a look online & I can get the whole front set up for about £250 all in,

Got to be worth a look if it gets the car back on the road sooner than 3 months.

What do we all think?

[martauto]

Assuming a rebuild kit is cheap enough, could you not rebuild to get it back on the road for now, and then replace in 3 months when the caliper turns up?

Fingers crossed this is the final piece of the puzzle though!

This is what I think and was going to say.
If it works then you have eliminated the issue but if you are still in the same situation then you have saved three months and a few quid taboo.

Mart.

[steve_k]

Assuming a rebuild kit is cheap enough, could you not rebuild to get it back on the road for now, and then replace in 3 months when the caliper turns up?

Fingers crossed this is the final piece of the puzzle though!

This is what I think and was going to say.
If it works then you have eliminated the issue but if you are still in the same situation then you have saved three months and a few quid taboo.

Mart.

Thanks guys that's partly my thinking as well

As for the idea of using mk3 mondeo front calipers & audi discs? Well I've just had a look & the discs I've currently got will fit perfectly, so if I did go down that route it would be a cheaper option to consider as I can get the calipers & brackets from a mate who's breaking a mk3 st220 & it would take me about a day to fit it all (just need longer caliper bolts).

As for the rebuild kit? Well I'm waiting to hear from hi-spex about that as well & from what I can gather the cost would be in the region of £100 (4 new pistons, & a full set of seals & dust boots).

So it looks like I need to sit down (with a beer or several) & do some serious thinking.

Tempted by the mk3 st220 kit though.

[martauto]

Just a thought....................why not strip the caliper very carefully ,trying to keep all the seals ,clean up and rub down the pistons and bores so you can "make it work" and go from there.
You just may get some idea if this is the problem.

Mart.

[steve_k]

i might do that tomorrow if it dont rain, can't hurt to try as i weigh up my options.

[fixedwheelnut]

i might do that tomorrow if it dont rain, can't hurt to try as i weigh up my options.

you could also clamp the hose to the offending calliper and see if it rectifies the pedal problem.