why brake-bomb blows?

[timucin]

i have that be-bep sound and red light on my screen which makes me sick.
did pedal test yep its gone.
i want to know why bomb blows? what can damage this stuff?
thnx

[Michel]

AFAIK the bomb has a valve in it which fails gradually over time.

When it no longer keeps pressure to within the original specs. the warning light comes on.

If it comes on every time you start the car after it standing for a while, say over night then its still working, just not very well.

It comes on whilst he engine is runnig or you are moving its totally dead and needs changing.

The brakes obviously need the additional help from the bomb if the engine is not running and I seem to recall the power steering was also affected.

[Lee]

Isn't there a diaphragm inside that perishes after a while? Am not an expert on this component!!

[The Spanish]

Is the warning light similar to this ((!))

Because for the past year I get this light on some cold mornings and then it dissapears.

My Car seems to loose some hydraulic fluid from the steering I thought it was due to this because it needs very little refilling every 3 months.

Now that I think about it sometimes it also comes on after refilling ummm maybe a new brake bomb needed

Cheers

[newsh]

To the best of my knowledge.

The bomb has a diaphragm in it with inert gas (nitrogen?) behind it under serious pressure, the system pumps in fluid to a preset pressure which is then used as the brake assistance, like a servo. Over time, as Lee says, this diaphragm can perish or rupture and the gas is lost. Its very important to use the correct fluid in the system for this reason, mixing the different kinds can lead to early failure.
Normally aspirated cars have a vacuum powered servo for the brakes, on a turbo car vacuum is not always present so we have a pump-up bomb instead.
It's called a bomb not, as you would think, because of the shape, but because of what will happen if you try to remove it without letting off the pressure. Even with a worn out one always pump the pedal 20-30 times to make sure all stored pressure is gone.

HTH

[Michel]

Lee

You're right its the diaphragm which perishes...

The Spanish,

I'd get the bomb changed at some stage rather than leave it.....that's how mine was behaving nand whilst it does work it is on its way out.....I spoke at length to AmD about it before getingit changed. One of their customer had a bomb behaving like this an had an engine problem whilst driving....no brakes to speak of once th engine died....on fun.

Personnally having had a Mk 2 Golf Gti throw a rod thro the block whilst on the right hand lane of the M25 at 75mph brakes in that type of emergency are a real help......so I got mine changed sooner rather than later.

[The Spanish]

Thanks a lot Michel,

I will change to bomb as soon as possible.
Some Idea of the price?

Thanks,
Rafael

[Michel]

Cannot remember off hand, I'll have to look it up.

However I think its one of thosse, whilst your are there type ooperations...change this and that just becuase you can whilst working on the bomb.

I'll see hte docs this evening and get back to you.

VAGparts may be able to help you on cost...I got mine from Audi ....

[porkkis]

The thing is as newsh said except the name. It really comes from the shape. It's totally safe component to work with.
Pressure is around 70-75bar when new, 0bar when totally dead.
New bomb costs around 400e new (doh!).
There are aftermarket replacements made by Febi-Bilstein for half the price.

When renewing the bomb change the hydraulic oil at the same time. Most of it comes out when you remove few of the hoses. Rest when steering is turned lock to lock few times to empty the power steering. Clean the mesh "filter" in the container at the same time. Use only good quality hose clamps securing the return hoses as they usually do leak a bit.
Use only original hydraulic oil or similar. Febi has a cheaper synthetic option that I use without problems. Half the price again.

[The Spanish]

Thanks Pokkis

400 Euros!!!!!

Money leaking never stops

Cheers,

Rafael

[Stick Insect]

can they not be re-charged like Citroen cylinders?

A company called Westroen in Manchester does the Citroen ones for £30.

[desmo888]

A guy here in the U.S. recharges them in his basement for $60. I have used two so far (on different cars), they work great!
The nice thing is that the valve is there to recharge it should it go low again.

[desmo888]

Originally posted by porkkis

When renewing the bomb change the hydraulic oil at the same time. Most of it comes out when you remove few of the hoses. Rest when steering is turned lock to lock few times to empty the power steering. Clean the mesh "filter" in the container at the same time.

Yep - good advice. Check www.20v.org for more tips. This part is the same as our lame 7A powered cars...

[timucin]

mine started this light problems just after brake fluid change. can it be a mistake done during that operation?

[timucin]

Originally posted by porkkis
The thing is as newsh said except the name. It really comes from the shape. It's totally safe component to work with.
Pressure is around 70-75bar when new, 0bar when totally dead.
New bomb costs around 400e new (doh!).
There are aftermarket replacements made by Febi-Bilstein for half the price.

When renewing the bomb change the hydraulic oil at the same time. Most of it comes out when you remove few of the hoses. Rest when steering is turned lock to lock few times to empty the power steering. Clean the mesh "filter" in the container at the same time. Use only good quality hose clamps securing the return hoses as they usually do leak a bit.
Use only original hydraulic oil or similar. Febi has a cheaper synthetic option that I use without problems. Half the price again.

where can i get febi-bilstein bombs?
thnx