My brother was helping me today with the car and I attempted to bleed the brake lines he told me that the brake master cylinder is bad because there was no pressure at all after pumpimg the brake pedal even with the engine running. He has a friend who worked on some puntos and he said his friend confirmed that it was not good.


Is this so?
Can i get a kit and have it repair or willl I have to get a new one?
Will the punto's brake cylinder fit it?

It is a 1996 Brava 14cc 12v manual.

firstly, there is only 1 brake that you can bleed at first, if you try any others you will not get any fluid out. the brake bleed order is very important and must be followed. read your haynes manual and try doing it again following the instructions closely.

master cylinders very rarely need changing, infact i've seen about half a dozen cases where the master cylinder was changed, and not once did it fix anything. its always a problem elsewhere.

what is your actual problem?

One of the back brake lines was busted so i made a replacement and refitted it then I undid a bleed nipple while changing the front pads then retighten it.
Now that the engine is starting I tried to bleed the system starting with the right front wheel, no fluid came at the nipple and the brake pedal had no pressure even with the engine running the pedal went straight down.
In what order should I bleed the system? I dont have a haynes manual.

front left, back right, front right, back left.

you cant bleed a back brake unless the wheel is on the ground (or suspension in equivalent position), because the brake pressure proportioning valve only operates when the rear suspension is in driving position (not jacked up)

the car is on the ground, I guess I will have to try the order and see what happens.

jug said:

front left, back right, front right, back left.

you cant bleed a back brake unless the wheel is on the ground (or suspension in equivalent position), because the brake pressure proportioning valve only operates when the rear suspension is in driving position (not jacked up)

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today i tried to bleed the brakes starting with the front left and no fluid appeared at the nipple so I stopped after a couple tries
I also notice as the brake pedal was depressed a sound like air escaping could be heard coming from the pedal area. What is this?
My brother had previously said that the diaphram in the master cylinder is gone(faulty) Is this so?

the noise of air is because there is air in the master cylinder, so you are pumping air, that is normal, when the noise changes you know you have fluid in it. once you pump air out the master cylinder should suck fluid in when the pedal is released. the brake system is designed so a dry master cylinder will still be able to take fluid from the reservoir, but you need to fully pump the brake pedal a good few times. try it with all bleed nipples open and the lid off the reservoir. if it still does not take any fluid from the reservoir then i would try replacing the master cylinder, although i've seen several cases where the master cylinder was thought to be faulty and in every case it was later found to be fine. its often difficult getting a dry master cylinder to take fluid which makes people think it is faulty. i'm not saying yours is definately not faulty, but i'm always very suspicious of faulty master cylinder claims.

Well I tried bleeding the brakes with only one bleed nipple undone that was the left front. No fluid appeared.
I will try to remove all the bleed nipples and see what happens the next time. The car is parked facing up hill I dont know if that will matter, but I am will to try almost anything now.:bang:
I had change one of the brake lines from where it joins the clyinder to where it connects under the passender seat(RHD), dont know if that have anything to do with the problem either.
I sure hope it is not the master cylinder.

Well I tried bleeding the brakes with only one bleed nipple undone that was the left front. No fluid appeared.
I will try to remove all the bleed nipples and see what happens the next time. The car is parked facing up hill I dont know if that will matter, but I am will to try almost anything now.:bang:
I had change one of the brake lines from where it connects to the clyinder, to where it joins under the passender seat(RHD), dont know if that have anything to do with the problem either.
I sure hope it is not the master cylinder.

I moved the car tried too bleed the brakes again and you wont believe what happen, the nipple on the rear back wheel broke. What rotten luck? :bang: and to add to that my computer broke down:bang: :bang: . Can my luck get any worst?
So I have to wait until i go to work or go by friends to use a pc.

After I had given up I noticed that the brake fluid left in the reservoir had darken in colour. Before I could see to the bottom of the reservoir form the inside now I cant, is it that the fluid needs changing?
I think someone had put dot 3 instead of dot 4 brake fluid into the reservoir previously. What effect can this have if there is any?

I forgot to mention that when pumping the brake pedal that the fluid in the reservoir dont get any lesser(go down) and splashes up out the opening of the reservoir.

i know of a break master cylinder dying on a 1.6 so its not a completley unlikey cause, but granted it is running a pair of brembo 4 pots :devil:

as for the remainder of the issue im afraid im a bit of a novice in the respect that i cant really help im afraid, i can change parts etc and get dirty, but breaks are a bit of a grey area in my knowledge, so i will be keepoing note and see what i can learn

Andy_sx said:

i know of a break master cylinder dying on a 1.6 so its not a completley unlikey cause, but granted it is running a pair of brembo 4 pots :devil:

as for the remainder of the issue im afraid im a bit of a novice in the respect that i cant really help im afraid, i can change parts etc and get dirty, but breaks are a bit of a grey area in my knowledge, so i will be keepoing note and see what i can learn

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About the master cylinder on the 1.6 I dont know, you see I live in the Caribbean so getting that part will be a problem. I am hoping that if it is the master cylinder that it can be repaired.
I am a bit of a novice myself. After the mechanic gave me the run around for months I got a recker to take the car home and have been doing things myself with some help at times.

dot3

even dot4 isnt good enough imo. i only use dot5. the main noticable difference is how sharply the brakes react to pedal movement. although i wouldnt think that could cause bleeding problems. i've never seen the fluid get darker for no apparent reason. thats strange!

maybe its time to use a bleed kit, they have one way valves so when you pump air out, fluid will be sucked in by the master cylinder when you relase the pedal. it seems this isnt happening now because when you release the pedal air is going back in through the bleed nipples.

if you havent got a bleed kit and cant get one (only cost £1.99 in uk) then try this using 2 people:

open front left bleed nipple
press brake pedal
close bleed nipple
release brake pedal
open front left bleed nipple
press brake pedal
close bleed nipple
release brake pedal
open front left bleed nipple
press brake pedal
close bleed nipple
release brake pedal
open front left bleed nipple
press brake pedal
close bleed nipple
release brake pedal
open front left bleed nipple
press brake pedal
close bleed nipple
release brake pedal

now see if the brake fluid level in the reservoir has dropped. if it has, do the same on another bleed nipple, until all 4 have been done, making sure you keep the reservoir topped up so fluid is above min at all times.

if this doesnt work, try feeling for air coming out the bleed nipple when you press the pedal, and air getting sucked back in when you release the pedal with the nipple still open. if you fell any air flow or pressure it means the master cylinder is working, it just cant get a supply of fluid. if that happens i would try pressurising the reservoir while repeating the bleed procedure mentioned above. to pressurise it you can use a bottle which fits in the brake fluid reservoir filler cap hole (add a bit of tape to make it an airtight fit), cut a small hole in the bottom of the bottle and blow hard into it when the pedal is released with the bleed nipple closed. hopefully this should force the fluid into the master cylinder. once you get some fluid in the master cylinder it should build pressure and start to take fluid without any help.

there is another option, buy me a plane ticket to the caribbean for a 2 week holiday and i'll bring a whole box full of parts and fix it for you

jug said:

dot3

even dot4 isnt good enough imo. i only use dot5.

buy me a plane ticket to the caribbean for a 2 week holiday and i'll bring a whole box full of parts and fix it for you

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lol well if I could I would.
With youre knowledge and experience I will be glad to have you in my corner or associate with you any time. You are a God sent, without you i dont know what we in this forum will do.
So on behalf of every member and all readers Thank You Jug For Everything.

About the dot five my owner manual recommends dot4.
I know that dot4 have a higher boiling point than dot3.
Is it the same with dot5 and dot4?
If i use dot5 in the car(1996 1.4 Brava sx) like you do in yours will it be ok? If it is ok I will probably be using the dot5 instead of dot4..

I had manage with some help from my wife
1. pump the pedal then after a couple of pumps (she)
2. hold the pedal down(she)
3. unscrew the nipple(me)
4. retighten the nipple(me)
this process was repeated a few times.

I plan to disconnect the brake lines at their connections and look for fluid flowing. I had to do this procedure with the wiper system to get the water to flow. I heard the motor worknig but did not get any water on the windshield.
I got the system to work eventually. It was blocked by the y junction after it had left the reservoir. I poke a pin in and water flowed after I reassemble though I have to go back at it. I know what the problem is and will fix it again after I get other problem sorted.
I will also give your suggestions a try.
Thanks for everything Jug.

bajeknight said:

I had manage with some help from my wife
1. pump the pedal then after a couple of pumps (she)
2. hold the pedal down(she)
3. unscrew the nipple(me)
4. retighten the nipple(me)
this process was repeated a few times.

Click to expand...

that would not work. you must do it exactly like this;

1. open bleed nipple (you)
2. pump pedal once, and hold it down (her)
3. close bleed nipple (you)
4. release pedal (her)

repeat this a few times and fluid should start to fill the master cylinder.

if dot4 is recommended, obviously using it will not be a problem. i only use dot5 because it is not water miscible, unlike dot3/4. dot3/4 will need to be replaced every 2-3 years, dot5 is often ok to leave for 5+ years with no noticable loss of braking efficiency. when i buy a new car i tend to change all fluids, such as antifreeze, brake fluid, etc. when i do this i almost always upgrade to dot5. if you change to dot5 you need to fully remove the dot4 by bleeding all brakes until pure dot5 is in the system (mixing can cause silicon gel to form). if your car is currently on dot3/4 i wouldnt bother changing to dot5, just use superdot4 instread, it mixes with dot3/4 but it has a higher boil point and is harder to compress so the brakes feel sharper.

How easy is it to change to dot5?
What is the process?
I will probably change to dot5 sometime after I get the car on the road probably in a couple months or a year or two

you must remove all the dot3/4 fluid, but you cant use anything other than brake fluid to flush the old fluid out (anything else can damage ro contaminate the brake system) so you need to drain the fluid reservoir, fill it with dot5, then bleed each brake while topping up the reservir until you are sure that all the old fluid has been removed.

i've done this on several cars and never had a problem, but you need to remember that the silicon in dot5 can form a gel when mixed with dot3/4, so try to do the change over quickly. you dont want gel to block up the brake pipes. i know someone who did manage to cause a blockage (on a fairly new BMW) but i'm fairly sure he didnt listen to me and just added a load of dot5 to his dot4, trying to save time. the fool

Don't forget to bleed the clutch too!

good point.

jug said:

that would not work. you must do it exactly like this;

1. open bleed nipple (you)
2. pump pedal once, and hold it down (her)
3. close bleed nipple (you)
4. release pedal (her)

repeat this a few times and fluid should start to fill the master cylinder.

Click to expand...

I did exactly that today repeating the process twice and still did not see any fluid flowing
However I disconnected the brake lines at both front wheels where the metal line joins the rubber line, one at a time,starting with the left first

At the left; fluid flowed quite freely and I reconnected the lines and took out the bleed nipple and no fliud came.

At the right; the fluid didnt flow as freely and after a while no more fluid flowed and no fluid came at the nipple either.

Is there a possible blockage thats affecting the braking system ?
Is it normal the fluid loss difference between the right and the left ?