Spongy Brakes & Warning

[Fragmaggot]

Gentlemen,

My missus's car (1999 VT) has always had spongy brakes. Today however, the handbrake warning was staying on and beeping. I took the car around the block, locking the brakes occasionally to see what happened. The pedal depressed all the way before it even begun to stop, and then it still took a while.

From what I've read researching this forum its either:
1: Brake Fluid is low
2: Brake Pad's are worn

As I'm really inexperienced with cars I was just wondering if there is an easy way to tell which it might be? E.g. Maybe get under the car and try to see brake pads to determine wear; or check brake fluid somehow.

Thanks guys,

Frag.

[slowandlow]

cripes dude. sounds pretty bad.
keep an big eye on the brake fluid level in the master cylynder. it sounds like you have a fluid leak or something bad anyway.
i would take it to brakes plus or your mechanic strait away on this one. if it goes completely u might be left with no brakes at all. trying to pull up at a stop sign at a busy road, or not be able to stop to pull up behind some expensive car, or a person.
dont risk driving it till you suss it out please. in an older car i had, the master cylinder went when i was trying to stop from a low speed thanks goodness, going down a slight hill. got the bad pedal, so some slowing, but i got worse pretty quickly. there was a really nice new beamer going past the intersection i was coming to and i was pretty much lining it up. i had to go up a gutter at low speed, and cut the corner on the footpath, and stop using the give way sign brake (i was nearly stopped after mounting the gutter).
and all this was only from doing 10 or 15 kph friggin scary, luckily no real bad damage. i got it towed strait to mechanic and got the thing fixed luckily
point being, it could happen anytime, at a higher speed or whatever, and u might die or kill someone
sorry to bang on

[Fragmaggot]

Yeah mate not going to drive it, after the test drive i parked it in the driveway and told her not to touch it just trying to work out the problem, and see if i can fix it myself or if its a professional job... students... poor... etc thanks for ur concern!

[slowandlow]

so was the brake fluid level low? if you take off the wheel its easy to see if the pads are worn. also look around the wheel and the brake caliper for any leaks. might as well check all four one at a time. thats a start at least. there should be something on this site in regards to the symptoms u have. try using a few different wordings of your problem in a search, and you might get some extra thread results. otherwise, someone on here who knows about this stuff will give u some advice eventually.
at least u have parked it for now anyway

[Manasvxv6]

Check for any splits in your brake lines sounds to me like you have a leak somewhere also check on your booster to see if it's wet sometimes the seal behind the master goes

[Fragmaggot]

Hey Mana, thanks both of u for ur replies. Could u please tell me where i can find the 'booster' and the 'master', because I'm not that sure what or whree they are also, the brake lines... are they just in the engine bay, or do they run the length of the car underneath it? Thanks.

[BlackVXGTS]

As others have said, it sounds like you either have a major leak in your brake lines or a major case of air in your brake lines. Have a look at your brake master cylinder to see if there is any fluid left. The master cylinder has two "compartments", one for the front brakes and one for the rear brakes. From the symptoms you have described it sounds like you may have had a leak in one of your front brake hoses (this happened to me recently). Because of the split master cylinder you will have rear brakes but no front brakes so your braking ability is severely compromised. If the fluid levels in the master cylinder are OK then it's probably time you replaced your brake fluid and bleed the brakes to get rid of any air in the system.

[Sabbath']

Considering your diagnostic technique was driving it around the block and randomly locking up the brakes, i'd say taking it to a qualified mechanic should be your next, and ONLY step when if comes to fixing this problem.

[Fragmaggot]

My 'diagnostic technique' was just to suss out what the warning light was when me missus pulled over and came and told me the problem I was planning on driving it to the mechanic but now i think that's an irresponsible and reckless idea. I will still have a look to see if i can find any leaks, but i think youre right - next stop: mechanic. Hope its not too expensive though

[pablo]

Sounds to me like a simple case of poor maintenance!...........Worn brake pads won't give you spongy brakes, but air in the system due to no fluid in the brake master cylinder reservoir will, (and will illuminate the brake warning light). This cylinder is found under bonnet, on the drivers side attached to a round, black container about 250mm diameter, on the fire wall, (brake vacuum booster). The reservoir (white opaque plastic) has a black, oblong top held down with a metal clip. Carefully undo it and have a look inside, the fluid level should be between the MIN & MAX marks on the out side. Also, remember that brake fluid will damage your paint!

[Fragmaggot]

hEy Pablo and thanks everyone for your replies. I checked the brake fluid, and its completely empty. It is a case of bad maintenance, she's not serviced it in 20000 kms despite my protests; but what can you do... Gonna chuck some brake fluid in and attempt to bleed the system this weekend!

[Munz]

if its empty then you have a leak somewhere!!!!

[monkeys437]

Hey Buddy, as Munz said your obviously leaking fluid from somewhere.

Now full respect for trying to do some work on your own to learn and save money, but i'm not sure brakes are the best place to start the journey.
I'd be calling one of those mobile mechanic mobs to come and find and fix the leak, and replace the brake fluid so you don't have to drive it. Its not worth taking the risk with your life.

[m1lky]

You can have a look yourself. Take the wheels off and check that there isn't fluid on the lines that go to the calipers.

As above you have a leak somewhere

[gossie]

When did you last check the brake fluid? When was the brake fluid last changed?......i.e. full system flush. Brake fluid does not last forever. Your VT books will tell you that. Service book should tell you when last changed.....if at all.

With all due respect, I would suggest very strongly with your lack of mechanical expertise you have the vehicle flat towed to your nearest brake repairer. Good luck.

[pablo]

I doubt very much that there is a 'leak' ...why should there be?.....The master reservoir doesn't hold much fluid, and as the pads wear the calliper pistons move further out of their cylinders to take up this wear and this fluid flows into the cylinders to occupy that space. If the master reservoir wasn't full to start with, it will be empty before the pads need replacing.

[m1lky]

That's true. Are both sides of the reservoir completely empty? Your right if you had a leak front or back would be down and the other wouldn't be so. Helps keep your braking safe, in the event of a fault.

It's pretty easy to tell if your pads are low with the wheels off.

Either way if they're spongy there's air in the system so the system needs topped up and bled at the very least. You need two people and it's s bit time consuming but not hard. There are YouTube videos and heaps of write-ups on how to do it if you search google.

[pablo]

.....and if your lucky and the air is not in the lines, but in the master cylinder only, it 'may' bleed itself enough to give you a better brake after you top up the reservoir and let it stand for a while, then give the pedal a few light, short pumps. I have gotten away with this on other cars, but I don't know about the Commy's.

[Hangman]

Take it to a mechanic, if you don't know what you're doing, even if it means getting it towed. I'm all for people working on their own cars, but brakes aren't the best thing to start playing with if you're not sure.

I'm not having a go at you, but you didn't even know the master cylinder or booster was, or where to find it.
Brakes stop the car and potentially save your life...

[Fragmaggot]

Thanks again everyone for your replies. Today I filled the master cylinder with brake fluid, and proceeded to bleed the brakes in the correct order. The back 2 went fine, thick streams of brake fluid busted out as they should. With the front 2 however i started to run into problems.

The front passenger nipple would sputter and spit, then dribble fluid. I had the missus push and hold while i cracked and tightened. Then i had her pump and hold again, while i cracked. i did this about 30 times with the same sputter before i decided to do the 'tube and bottle' pumping method. No matter how much we pumped bubbles kept rising in the bottle.

The driver side nipple just dribbled, no air sputter. I noticed though that the disk and caliper would shift nearly an inch if i pulled it (Is this normal?)

We both have VT's, and mine is maintained, so i compare things on hers with mine. When you depress my brakes it makes the airy 'hiss' noise as it goes down, and then the noise stops.

But after all this I went into the drivers seat and compressed the pedal. With the engine turned on, and the pedal depressed, and the hissing continued non-stop while the pedal was depressed! I also noticed that the brake lights were stuck on. For now, I've packed the switch with some cardboard to stop the lights from draining the battery.

I then went to put the car back in its spot. Placed it in drive, with my foot on the brakes... NO BRAKES WHATSOEVER! I quickly stopped the car with the hand brake, but man am i ####ing glad this didnt happen while she was doing 80 kmph...

This fill and bleed exercise was just to try and get some more diagnostic information, but i definitely know its time for professionals to do the work.

I dont care that she hasnt had it maintained, all i care is that she learns from this how important regular servicing is. Hers, or someone elses lives could have ended due to negligence, and budgeting.

Thanks for all your help.

Frag.

[monkeys437]

I doubt very much that there is a 'leak' ...why should there be?.....

Considering the reservoir is empty and the pedal goes to the floor I think a leak is a massive possibility. Even with worn down metal on metal brakes the resi would not be empty

[Hangman]

Considering the reservoir is empty and the pedal goes to the floor I dont think a leak is a massive possibility. Even with worn down metal on metal brakes the resi would not be empty

I agree. I've seen metal on metal brakes and while the fluid may drop a little to compensate, the pedal will still have feel and they'll still stop the car. It may be noisy and not as effective as good pads and discs would be, but they will stop it.

You'd be doing well to empty a reservoir just by having worn pads.

Either way, the OP is doing the right thing IMO. Get a professional to have a look.

[m1lky]

Any news from the mechanic?