vn brake booster leak

[Ben.]

hey

my brakes on my vn commodore have been getting really hard to push down there is pressure but it will loose it when off , Ive noticed there to be fluid inside the resior filling into there rubber and in between the booster and master cly weeping i know there are to bolts n nut holding it thou the firewall is there a gasket between ive just replace front pads n rodors bleed

thanks for your help Ben

[VT-565]

If the booster diaphragm has a split, you will hear hissing when your foot is on the brake, this is manifold vacuum running through the split.

Sounds like your master cylinder is rooted.
Just buy a new one from repco or wherever, then make sure you flush ALL your brake lines again to get any residual crap out.
Also give the car a good clean where the brake fluid has been leaking.

Good luck.

[Ben.]

ok thanks wats the correct way to bleed the cly before it goes in

[VT-565]

You mean remove the brake fluid before you remove the cylinder? make sure you drain plenty of fluid from your caliper to ensure you're not spilling that shit everywhere.

I recommend buying a brake bleed kit if you don't have one already, means you can do it yourself and produces a good result.
Bolt the new cylinder in as per usual, put your lines back on, you might have to swap the low level switch over too and plug it in.
Top up with brake fluid and bleed the furthes corner first, so passenger rear brake, bleed that until the clean fluid comes through and lock the bleed nipple off when there are no bubbles in the line.
Make sure you keep an eye on the master cylinder reservoir level, as if you pull air through here, you have to start it all over again.
Then do the next closest brake which would be drivers rear brake, then passenger front then drivers front.
If you do it like this, you can be assured that you've cleaned the brake lines as best you can and with no air in the system, it should keep good pedal feel provided there are no other problems.

Your brake fluid in theory should be changed every 12 months, it absorbs water from the atmosphere and this goes straight to the bottom of the system, re: your calipers and wheel cylinders.

Hope this helps

[Ben.]

thanks for all your help ive going to wreckers bought better rubber mould thingy like new and resealed

[VT-565]

so was it the booster or the master cylinder??