Brake Servo

Ricardo

A2OC Donor
Hi

Got a 2002 A2 1.4 TDi 75PS with hissing brake pedal (hiss goes away when pedal pressed).

Having poked about in the footwell it appears there is something wrong with the rubber gator on the front of the brake servo. I have moved it about and reduced the hiss but to take a proper look I need to remove the servo...any ideas? - it looks as though the servo is sandwiched inside the car between the bulkhead and pedal box casting. Just wondering what I will need to remove to gain access...gulp...
 
I think you need to get yourself a copy of elsawin, which has detailed guides on how to remove parts.
The servo is connected to the master cylinder through the bulk head. If you have hissing it sounds like the seal on teh servo is shot
John
 
The leak is from the gator which sits between the servo and the brake pedal rod (the servo shaft). It looks like the gator has come off the lip in the servo body but its so tight I cant get my hands in to try getting it back on...I think thats it anyway - the gator does look "complicated" with vent holes etc so I might be wrong but either way it needs to come off...
 
I'm going to resurrect this thread....... did anyone come up with a non dealer fix for this problem?
Needless to say my other half's A2 1.4TDI has developed this delightful wheeze as you release the brake pedal....although, as yet, braking performance is unaffected.
 
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Ive replaced a master cylinder , took about 4 hours and not perticularly hard just awkward , the master cylinder securing bolts are under the dash but you can get at them all but not much space under there, you need to remove engine mounts and lower the engine on a tdi about a foot until you gain enough room to get the master cylinder out, i only had to disconect turbo pipes and a few wires to enable the engine to get low enough .. youl also need a plastic part that locks the mastercylinder push rod to the brake pedal as i couldnt find a way to remove this without braking it ... 1H0 721 357
 
servo swap

Just done a servo swap - a few tips:


Under Bonnet

- Remove wipers and the black plastic cowling that runs across the base of the screen
- remove wiper motor (three bolts/nuts)
- remove pipes on master cylinder
- remove master cylinder
- remove vacuum hose - carefully not to snap small secondary pipe.

Inside car

- remove under dash trim
- remove carpet in drivers foot well
- you should now see a black steel shaft running between the pedal and the servo actuator
- there will be two hex locking screws each end - remove these
- Then remove the two bolts each end of the shaft
- the shaft will then drop allowing access to the remaining connection to the servo shoe
- this will also give access to the plastic retaining clip on the end of servo rod - you may be able to take off but better to break it and replace - only £4 from dealer
- assume you have a new clip - remove the shaft and fit the clip off the car - A LOT EASIER!
- Then using a 1/4 drive socket with 2 or 3 extensions and remove the four 13mm nuts holding the servo in place

Back under bonnet

now manoeuvre servo out - tight but comes out.

refitting is reversal of above but fit shaft first inside with new plastic retainer then push in servo - servo ball end should clip home.
then tighten up 4 nuts then inside.

Hope that helps

Brent
 
It was a while ago but to confirm, my garage diagnosed the hissing as a leaking/dead servo and hence I got them to replace it.
 
Ditto! Just discovered n reporting! Vaccum tested frm tandem pump end and it won't hold it. Misty inside as shows in the pic.
 

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servo swap

Just done a servo swap - a few tips:


Under Bonnet

- Remove wipers and the black plastic cowling that runs across the base of the screen
- remove wiper motor (three bolts/nuts)
- remove pipes on master cylinder
- remove master cylinder
- remove vacuum hose - carefully not to snap small secondary pipe.

Inside car

- remove under dash trim
- remove carpet in drivers foot well
- you should now see a black steel shaft running between the pedal and the servo actuator
- there will be two hex locking screws each end - remove these
- Then remove the two bolts each end of the shaft
- the shaft will then drop allowing access to the remaining connection to the servo shoe
- this will also give access to the plastic retaining clip on the end of servo rod - you may be able to take off but better to break it and replace - only £4 from dealer
- assume you have a new clip - remove the shaft and fit the clip off the car - A LOT EASIER!
- Then using a 1/4 drive socket with 2 or 3 extensions and remove the four 13mm nuts holding the servo in place

Back under bonnet

now manoeuvre servo out - tight but comes out.

refitting is reversal of above but fit shaft first inside with new plastic retainer then push in servo - servo ball end should clip home.
then tighten up 4 nuts then inside.

Hope that helps

Brent
Quite an old thread now but which model of A2 do these instructions refer to?
 
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