Hydrolic to vacum servo upgrade

[bilko0795]

As above can anyone tell me whats involved and what are the benifits to this upgrade im sure some one has done this recently i think it was tonks on Andycoupe77s car.

Also what parts would i need and is it worth it.

[Error404]

Its not really an "upgrade" so unless you have something wrong with your hydro assist you won't gain anything.
Most people including me swapped to vacuum as the brake bomb is now NLA and the hydraulic servo is outrageously expensive. Vacuum is a much simpler, more reliable and cheaper to maintain set-up

You need a servo - 893612107A. Easy to find used ones but I would buy a new one so at least you know it works (BTDT)
Vacuum pipe with check valve - 8A2611931C
Additional inline check valve (optional) - 191611933
Vacuum hose - IIRC 12mm ID
A vacuum fitting on the inlet manifold, the take-off for the carbon cannister circuit is a good size and location.
Cut the bracket off the suspension turret that the lambda plugs live on (this needs to be removed to fit the vac servo).
Single stage PAS pump or ghetto mod is remove the pistons from the S2 pump & plug the pressure line that used to go to the bomb.

[GazzaG60]

ill keep my 2 of everything then from the 6a

[Henkjan]

would a sort of vacuum pump be usefull (iirc the A6 TDI has it) or not required?

[Error404]

I guess if you plan to do a lot of left foot braking you will need a vacuum pump. For normal use you always have vacuum off-throttle, plus the booster acts as a vacuum reservoir for a couple of brake applications

[popdemonic]

I had vacuum booster from A6 C4.everything is bolt right up.you'll need All those parts to be completed the setup.unfortunately,i decided to convert back to hydro system fee years ago due to
my personal preference on a sponge feel on hydro pedal since i think i need more effort
on the vacuum booster.recently i found some UrS cars locally has done the dual diaphragm
booster on the car.the booster was taken from a passat ,A8 iirc.the bolt pattern is 2 bolts diagonally
which can bolt right up on the C4 firewall.the rest is the same as single diaphragm booster
conversion.if i would do it again i'll get a dual diaphragm booster on my car.it reauired much
lesser effort when applying the the brake.my country is stop and go traffic so the lighter
on any pedals is better on my situation.

[bilko0795]

Reason I am asking for advice is I have the brake bulb warning light permently illuminated and GregS said it could be a couple of things ,he checked the power steering cap to check if the little plunger was working it was ok but also suggested the bomb could be at fault but the brakes work really well ? So not sure what is wrong maybe it's electrical.

[Error404]

Try taking the two spade connectors off the pressure switch on the servo, if that cancels the warning you know you have low hydraulic pressure or a bad sensor. If so you can leave them unplugged for some peace and quiet

[bilko0795]

Cheers Alex will try that

[igor136]

Original Audi green hydro oil?

[rynaqui]

G00400 is what you want

[igor136]

G00400 is what you want

Green gold