The Project Pad

Hey folks, I have a quick question that you may be able to answer. I recently became the proud new owner of a 200 20v Avant. Pearl white, 120k on the clock, great overall condition with one minor exception: when I got the car, the pressure hose (aka the J-hose) to the brake accumulator had a nasty gash in it and leaked like a sieve. Rather than spending $250+ for a replacement, I had it rebuilt. The banjo fitting was re-used but the threaded fitting that connects to the damper pipe was replaced. The problem I’m now having is this: since I installed the new hose, the brake bomb will not re-pressurize. Here are the symptoms:

-The brake warning light is on constantly
-When the car is running and you firmly apply the brakes, there is a pulsing vibration in the pedal. It feels similar to ABS.
-Now the kicker: when you shut the car off and apply the brakes, the pedal is IMMEDIATELY stiff. I understand a working brake bomb is supposed to give you 20-30 applications of the pedal before the system loses pressure.

Another thing to note: before I replaced the hose, during normal driving, the brake warning light would sometimes flash when I first applied the brakes. I read on SJM that this could mean your accumulator is on its way out. Is it safe then to assume my brake accumulator is dead, or is my rebuilt hose somehow functioning improperly? It certainly moves fluid, but it occurred to me that the original hose might have been fitted with a check valve on the threaded end. Also, can the bomb be recharged or do I have to bite the bullet and buy a new one? Thanks for your input.

krieg80 wrote:Hey folks, I have a quick question that you may be able to answer. I recently became the proud new owner of 200 20v Avant. Pearl white, 120k on the clock, great overall condition with one minor exception: when I got the car, the pressure hose (aka the J-hose) to the brake accumulator had a nasty gash in it and leaked like a sieve. Rather than spending $250+ for a replacement, I had it rebuilt. The banjo fitting was re-used but the threaded fitting that connects to the damper pipe was replaced. The problem I’m now having is this: since I installed the new hose, the brake bomb will not re-pressurize. Here are the symptoms:

-The brake warning light is on constantly
-When the car is running and you firmly apply the brakes, there is a pulsing vibration in the pedal. It feels similar to ABS.
-Now the kicker: when you shut the car off and apply the brakes, the pedal is IMMEDIATELY stiff. I understand a working brake bomb is supposed to give you 20-30 applications of the pedal before the system loses pressure.

Another thing to note: before I replaced the hose, during normal driving, the brake warning light would flash sometimes when I first applied the brakes. I read on SJM that this could mean your accumulator is on its way out. Is it safe then to assume my brake accumulator is dead, or is my rebuilt hose somehow functioning improperly? It certainly moves fluid, but it occurred to me that the original hose might have been fitted with a check valve on the threaded end. Also, can the bomb be recharged or do I have to bite the bullet and buy a new one? Thanks for your input.

If you don't know when or if the accumulator was changed (and as a previous owner of 3 said 3B's) I have had to only change one out) You may be due. You can get a re-man fron David Case. I don't know ATM if new ones are available. I've been out of the 3B games for years now.

As far as the J-hose: You need 2-O rings on either side of the fitting @ the bomb. And 2 on either side @ PS pump end. ANY banjo bolt fittings IMHO should be NEW for they contain their own screens inside (you can slightly see them on an old one) But this isn't fully necessary just smart.

The rez has a filter you can replace inside. Easiest done when empty.

Hope this helps a little with what you have done thus far.

Thanks for the suggestions. I replaced the o-rings and hosed down the bomb-end banjo bolt pretty thoroughly with brake cleaner (as for the pump-end banjo bolt, I never removed the damper pipe from the pump.) My gut tells me that the bomb was on its way out and it just didn't like being de-pressurized when I removed the J-hose, but I'll poke around a bit more to be sure before I replace it. To that end, I found David's website (www.audibombs.com for anyone who might be reading this) and I'll definitely contact him about a re-man.

I think the new bomb is going to be the ticket here. Glad you found Davids website. I'll probably have to bookmark that for the future.

Sorry I can't help more, but please do post your avant!

There's a project thread in the works, I just need to take some decent pictures.