Mk3 Cavalier Owners Club | Vauxhall Cavalier Dot Com

My brakes wasn't working properly so i bought new rear brake cylinder and bled (ive bled brakes a few times) the brakes but still change.The master cylinder looks like its been changed over time,looks newish from the servo, but i can't be 100% sure.

What would be the best advice,change the servo first or change the master cylinder first.

First port of call would be to tell us why you think they aren't working

What are the symptoms?

Agreed -

What are the brakes doing - or not doing.?
Car pulling to one side.?
Brake pedal very hard?
Brake pedal sinking to the floor?
Brake pedal feels spongy?
Brakes snatching or dragging?

And is there a particular situation that causes this, or does it do it all the time?

Sorry about that.
The brake pedal feels spongy and goes near to the floor when braking.

Silly question but I presume you have checked for leaks at each wheel? And the flexi-hoses by the front struts?

Air in system, a leak, or a master cylinder failure. Was it a problem prior to changing the wheel cylinder? Old master cylinders quite often fail when manually bleeding brakes as the seals fold with the additional travel of the pedal.

I would suggest air in the lines.

I always found that pressure bleeding was the only proper way to sort this.
Normal methods never seemed to work.

I had an identical situation 15 years ago.
Replaced all discs, drums, pads and shoes.
Accidentally got air into the lines.
No amount of bleeding would work.

Got a new master cylinder, which was silly expensive... again bleeding didn't help.

Eventually got the car towed to the garage.
They fixed it by pressure bleeding the whole system.

Very thirsty on brake fluid but effective.

Yes,i checked for leaks.

Yes,i change the rear cylinders bc of the problem i had with the brakes.

I bled the brakes using a bled kit and 20lbs of pressure from tyre.I did this a few times bc the tyre valve connector was leaking out air.I then tried to manually bled the brakes bc the tyre valve was leaking.I pumped the pedal three times then releasing the bleed nipple,still no joy.I then bought a new tyre valve connector and bled them again with the bleed kit,still no inprovement in brakes.

Fair chance the master has died then

blowfelt wrote:...I bled the brakes using a bleed kit...

...I then bought a new tyre valve connector and bled them again with the bleed kit...

Did you bleed all four corners, starting with the one furthest away from the master cylinder?

Yes,i did bleed from the furthest which is N/S/R,O/S/R and so on.

I may try new brake shoes first bc i think the last owner didn't fit the properly,the shoes look unevenly worn.

Pull your handbrake amd then press the pedal. That will rule out the rear shoes. Then you could put pipe clamps on all 4 brake hoses one by one and see if it gets better. Then you can elimunate which corner is OK. But it does sound like master cylinder. Had it a few times now.

Do you mean clamp hoses for rear disc brakes bc my rear brakes are drums.I don't have hoses on my rear brakes.

You still have hoses mate, from the body to the rear beam

Ok!....If the master cylinder has packed up what other Vauxhall master cylinders fit my Cav TD?
Do i have to get a diesel master cylinder or will petrol ones fit diesel Cav's?

Another thing worth trying is leaving the brakes to gravity bleed them selves one by one. My sj will not bleed any other way what so ever (due to position of bleed nipple) I lift calliper up so bleed nipple is at top and crack it off until just fluid comes out consistently.
I don't really know what the difference could be other than position of the pipes and bolt spacing. Check some images to see if they look the same.

Problem sorted.I put new mintex brake shoes on and clean inside the drums.
I think i need to change front brakes also bc they don't seem to be that effective even though there is plenty of meat on them.

blowfelt wrote:Problem sorted.I put new mintex brake shoes on and clean inside the drums.
I think i need to change front brakes also bc they don't seem to be that effective even though there is plenty of meat on them.

Glad to hear it got sorted.

What pads do you have on there at the moment?
I recommend EBC ultimax pads. They are better than genuine GM pads and are very reasonably priced.

If there's plenty of meat on the pads then they shouldn't be at fault.

I don't know what name pads i have on front brakes,thinks they are cheap pads i bought from local auto shop.

Sribobby,even thought there is plenty of meat on the pads,they are cheap pads which maybe down to why they are not that effective.

If they are unbranded you will see a big difference going to EBC or even GM pads.

Fair enough but unless you got them from pound land they shouldn't be that bad!! Even cheap pads have to be approved and fit for purpose

sribobby wrote:Fair enough but unless you got them from pound land they shouldn't be that bad!! Even cheap pads have to be approved and fit for purpose

Not if they are ebay parts manufacured outside of Europe - they have virtually no quality control over manufacturing.

Thanks very much for helping me out guys.

Well he said he got them from local auto parts shop so I'm assuming they aren't from eBay. But stranger things have happened