[s-cars] Bleeding Pressure from the hydraulic boost system

[Cody Forbes]

I intended to reply to this earlier and forgot (quite busy), but I did want to clarify something. The accumulator is only for the braking circuit. After the car is off the ONLY hose that maintains pressure is between the accumulator and the brake booster. None of the steering circuit has anything to do with the accumulator at all. If that was the case you would still have power steering with the engine off for a short time, but that isn't how it works. There is a check valve in the accumulator that prevents pressure/fluid to feed back to the pump. There is a 0% chance that the x plug would be under high pressure after the car has been turned off for more than a few minutes. 

It's better to be safe than sorry for sure, but I figured it was worthwhile to also help clarify the functionality for educational purposes.

-Cody Forbes (mobile)

> On Sep 7, 2016, at 10:52 PM, Douglas Fifield <douglas.fifield at gmail.com> wrote:
> 
> Pump the brake 20-30 times (or until the pedal hardens up) with the engine off.  That will discharge the pressure stored in the accumulator.
> 
> D.
> 
> 
>> On Sep 6, 2016, at 7:56 PM, Larry <larrycleung at gmail.com> wrote:
>> 
>> Not looking to bleed the system. As you put it, it pretty well (at the point of the X-plug on the pump) will "self" bleed since its at the top of the system. The issue is, so long as the pressure accumulator (a.k.a. B_mb) is functioning correctly, opening ANY part of the system (rack, pump, booster, b_mb, lines) will cause very high PSI green gold (CHF 11S) to spew out, potentially 
>> with enough force to cause serious injury. So it's a REQUIREMENT to bleed off system pressure before opening the system, which in my case is to replace the O-ring under the X-plug.
>> 
>> 
>> Sent from my pocket electronic thingy
>> 
>>> On Sep 6, 2016, at 8:09 PM, Tony <tony.curran at sympatico.ca> wrote:
>>> 
>>> Hi Larry,
>>> 
>>> I believe the power steering hydraulics is self leveling. Just have to turn on and let it run for a while. 
>>> 
>>> Can someone else chime in if it's different.
>>> 
>>> Cheers,
>>> 
>>> Tony
>>> 96 S6
>>> 
>>> -----Original Message-----
>>> From: S-CAR-List [mailto:s-car-list-bounces at audifans.com] On Behalf Of Larry
>>> Sent: September-06-16 6:54 PM
>>> To: s-car-list at audifans.com
>>> Subject: [s-cars] Bleeding Pressure from the hydraulic boost system
>>> 
>>> I'm in need of replacing of my hydraulic pump's X-plug.
>>> 
>>> How do I bleed off the system pressure before removing the old O-ring.  Pump the brake pedal until the pedal goes hard?
>>> 
>>> LL-NY
>>> 
>>> Sent from my pocket electronic thingy
>>> _______________________________________________
>>> S-CAR-List mailing list
>>> http://audifans.com/mailman/listinfo/s-car-list
>>> http://www.audifans.com/kb/List_information
>> _______________________________________________
>> S-CAR-List mailing list
>> http://audifans.com/mailman/listinfo/s-car-list
>> http://www.audifans.com/kb/List_information
> 
> _______________________________________________
> S-CAR-List mailing list
> http://audifans.com/mailman/listinfo/s-car-list
> http://www.audifans.com/kb/List_information