Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

VH Brakes- help

lukadge

New Member
Joined
Jun 7, 2009
Messages
2
Reaction score
0
Points
0
Members Ride
VH SLX
Am having trouble with the brakes on a VH commodore.
Replaced the brake master cyclinder a few months back and all was fine for a couple of months before having a brake failure (brake pedal to floor) again. Bled the brakes and everything was going well until the other day when I was out driving and the brakes failed. Got the car home and the next day the brakes were okay (a little spongy.)
Usually only drive the car to and from work each day (about 5km) but on each occassion they have failed it has been driven a little further but by a little further I still mean under 40km.
The brake fluid reservoir is full, there are no signs of leakages along fuel lines, nipples or wheel cyclinders (newly replaced).
I am totally preplexed as to what could be causing this, any ideas?
 

havick vk

New Member
Joined
Aug 10, 2008
Messages
25
Reaction score
0
Points
0
Members Ride
vk commodore
long shot but maybe check the condition of the pads and rotors...sort of sounds like bad brake fade were wen the brake components get hot u begin to lose pedal just strange that it happens quickly and to such an exrteme mesure.
 

markovr

Well-Known Member
Joined
Nov 23, 2003
Messages
2,979
Reaction score
125
Points
63
Age
59
Location
northside brisbane
Website
www.cardomain.com
Members Ride
07vessv 94vr .04vz wgn,93vp wgn,82 vhV6 wgn 88 vn
If you are losing no fluid and all wheels are free and not dragging it has to be your master cylinder or booster...when you lose the pedal does it pump back up?....by going to the floor does it stop just before the floor and you still have brakes or do you have nothing?..I know if you pull the cylinder apart to recondition the seals but dont take the stop screw out totally or replace it after applying pressure to the piston you can nick a seal and on reassembly it will give you grief.
 

lukadge

New Member
Joined
Jun 7, 2009
Messages
2
Reaction score
0
Points
0
Members Ride
VH SLX
havick VK, thanks mate. Pads and shoes were also changed when I replaced the master cylinder. But yes it is odd and doing my head in.
markovr, after racking my brain I have decided it must be the master cylinder, guessing that it may been sitting on a shelf for some time and seals may have dried out before I bought it? I am not sure about the booster as if this failed I would think you would still have some pedal? Brakes would not pump back up and the pedal would drop completly but the next day all was good. This is why I am thinking fluid must be getting past the seal in the master cylinder, not air getting into the system. I will buy a seal kit this weekend and see how I go.
Thanks for your help I will keep you posted any other ideas pls let me know, ta.
 

kym192

kym j
Joined
Jun 9, 2009
Messages
55
Reaction score
0
Points
0
Location
south coast south aust
Members Ride
VH sl, VT berlina, VN berlina, VH SL\E
i had the same problem in my sl/e but i did the simplest thing and went to a vn and took its booster and everthing with it bolts strait in witht the usual anoyance of taking the thing apart but worked fine for me stopped that problem straight away only problem i found so far is the bracket to hold it to the strut tower is back to front but easly fixed, if all else fails just use the hand brake i did it for 90 km after a engine fire
 

jakbob

Lighten up.
Joined
Dec 23, 2008
Messages
201
Reaction score
2
Points
0
Location
Brisbane
Members Ride
VX SS, VC L, VK Vacationer
I had to drive a crappy old patrol once, and the buckets in the master cylinder were stuffed. Sometimes they would seal in the cylinder and the brakes would work just fine, other times they wouldn't seal and you'd have bugger all brakes. Was quite scary sometimes, not knowing whether your brakes would be there when you needed them.
 

griezy

Member
Joined
Jan 8, 2014
Messages
128
Reaction score
10
Points
18
Location
somewhere
Members Ride
1982 VH SL-X Wagon
Am having trouble with the brakes on a VH commodore.
Replaced the brake master cyclinder a few months back and all was fine for a couple of months before having a brake failure (brake pedal to floor) again. Bled the brakes and everything was going well until the other day when I was out driving and the brakes failed. Got the car home and the next day the brakes were okay (a little spongy.)
Usually only drive the car to and from work each day (about 5km) but on each occassion they have failed it has been driven a little further but by a little further I still mean under 40km.
The brake fluid reservoir is full, there are no signs of leakages along fuel lines, nipples or wheel cyclinders (newly replaced).
I am totally preplexed as to what could be causing this, any ideas?
im having the same problem, in my SLX VH wagon two years ago they completely failed, so i took it in to the mechanics (they installed a new master cylinder completely bleed the whole system and added new fluid),about a year later the pedal went strait to the floor again, took it back, and the mechanics put new seals in the master cylinder and bleed them again and today 1/3/20 coming from near bathurst to campbelltown they failed again (3 hour drive) , but after a while and pumping the brakes they come good again, but failed 3 more times afterwards but i made it
I have had about 35 cars in my life time all but 5 made before 1980 (mostly HQ'S HZ'S Toranas and escorts, i have never had brake failure in any other car

edited: the master cylinder is still full of fluid
 
Last edited:

vc commodore

Well-Known Member
Joined
Jun 18, 2014
Messages
5,358
Reaction score
2,114
Points
113
Location
south australia
Members Ride
vc commodore
im having the same problem, in my SLX VH wagon two years ago they completely failed, so i took it in to the mechanics (they installed a new master cylinder completely bleed the whole system and added new fluid),about a year later the pedal went strait to the floor again, took it back, and the mechanics put new seals in the master cylinder and bleed them again and today 1/3/20 coming from near bathurst to campbelltown they failed again (3 hour drive) , but after a while and pumping the brakes they come good again, but failed 3 more times afterwards but i made it
I have had about 35 cars in my life time all but 5 made before 1980 (mostly HQ'S HZ'S Toranas and escorts, i have never had brake failure in any other car

edited: the master cylinder is still full of fluid

Unfortunately it's the master cylinder that has failed again...I suspect, they just put new rubbers through the master cylinder rather than re-sleeve it, or put a brand new one back on
 

griezy

Member
Joined
Jan 8, 2014
Messages
128
Reaction score
10
Points
18
Location
somewhere
Members Ride
1982 VH SL-X Wagon
Unfortunately it's the master cylinder that has failed again...I suspect, they just put new rubbers through the master cylinder rather than re-sleeve it, or put a brand new one back on
Thanks, would it be worth getting a V8 master cylinder? Would it bolt in the 6 cylinder brake system with out modifications
 

vc commodore

Well-Known Member
Joined
Jun 18, 2014
Messages
5,358
Reaction score
2,114
Points
113
Location
south australia
Members Ride
vc commodore
Thanks, would it be worth getting a V8 master cylinder? Would it bolt in the 6 cylinder brake system with out modifications

6 and 8 cylinder master cylinders are the same.....The only difference is, the bore diametre....Most 6cyl ones are the some of V8 ones are 15/16, whilst the rest are 1" bore.

To tell what diametre the bore is, at the front of the master cylinder (furtherest point away from the booster), there is a flat section with the numbers 15/16 or 1"...
 
Top