I have a mk1 octavia vrs and plan to do a brake fluid change and am just wondering if anyone knows if the the brake system is pressurizedmany thanks

no sir,is not

Wonderful thank you

Need to use a pressure bleeder to flush it though as you may invert seals in master cylinder doing it manually and let level get to low in resivoir you may air block abs unit

Don't let it get too low, and don't forget to bleed the two nipples right under resevoir. Never heard of inverted seals, it has been a subject of much debate.

Ok is there also a pattern you have to bleed them in?

As above you have to use a pressure bleeder (Eezibleed or similar).

I think you start with the furthest away so NSR, OSR, NSF and then OSF.

Also give the clutch a quick bleed to as it shares the same fluid.

You got a proper brake pipe spanner? They can be quite seized and don't want to round the nipples off (ooo-eer missus!)

Phil

done 3 octy 1's up to now, complete fluid changes, one ran completely dry, all absolutely no problem, all no pressure bleeder, none with inverted seals.

I just used a clear pipe with a one way in it.

Edited 25 July, 201213 yr by Lofty79

Who says that rubbish "inverted seals" from manual bleeding,never saw a master cyl seal in his life.

done 3 octy 1's up to now, complete fluid changes, one ran completely dry, all absolutely no problem, all no pressure bleeder, none with inverted seals.

I just used a clear pipe with a one way in it.

You were just lucky... nothing else...

He was definitely not stupid

inverted seals is somewhat of a forum based myth. Stripping one of these down there is not much difference to the normal mc's of other cars. The seals do go past comfort when pedal pressed to floor but as for inverted seal???????? No, for this to happed there MUST be an underlying fault to which the mc would fail anyway.

Numerous garages have used the old one man bleed kits on these cars with no ill effects - when using proper proceedure, granted mine running dry was bad methodology and i shall never do it again, but i aint lucky.

Who on here has had inverted seals DUE TO BLEEDING, not just having them, actually directly caused by it????

Ok now am confused is inverting the seals a myth from just doing a basic fluid change and bleed?

IMHO yes myth, if your careful and keep it topped up, it should give you no problems. If your really worried only depress the pedal halfway during the bleed process

To be honest ive bled my rear caliper the manual way as our pressure bleeder was knackered at work and i was in a rush and didnt have any trouble with master cylinder.

Plus ive never had a master cylinder invert its seals but i tend to work on more newer stuff at work

I've seen two inverted seals in over ten years. It is possible but extremely rare. Were they faulty anyway? Who knows?

It is possible to get crud between the seal and cylinder, but this can avoided.

If you are going to bleed using the pedal, then press on the pedal before you start and put something under the pedal to stop you pressing it further. This keeps the seals on the clean, used part of the cylinder wall.

Is there not a procedure on vag com that can bleed the brakes,i know on our snap on machine at work there is a facility to do it but only on newer stuff,says can brake bleed procedure,obviously mk 1 octys dont run can bus,also in my 22 years as being a mechanic,i have seen a few master cylinders flip there seals when bleeding brakes,but only ever on vauxhalls,mainly mk2 and mk3 astras,cavaliers,also you had to watch when fitting front brake pads on them,not to push the piston back to quick or it would flip the seals in the master cylinder,but nowadays it is rare for a master cylinder to go.

Is there not a procedure on vag com that can bleed the brakes...

There is a procedure for removing air from the ABS block

see http://www.ross-tech...bsbleeding.html