80 series rear brakes not working

stoneddoodle · 25-07-2010, 10:52 PM

Hey guys and gals, ive had a problem with my rear brakes for a while now and my mech cant seem to fix it. Then rear brakes dont seem to work at all and i have tried to bleed them but nothing come out even with the weight of my whole body on the pedal. I have been told alot of things from diff people soo i was hoping someone on here may know or has had the same problem, one mech told me its the accumulator? some one said something else about some thing that controls how much effort goes to the rear brakes during braking, and someone else mentioned the master cylinder. Ok soo the pads are new i just spent just over a grand replacing the shocks and get the rest of the sus checked out and that all ok. it all started one day i was driving and slammed on the brakes to avoid a dog on the road right out side my house. drove in my drive way...... when i went to head of to work the next day its was as if someone had poured oil on my disks its took a lot long to stop the car tilts way to much forward and the pedal has become very hard. Remember this all happening over night since i slammed the brakes on. Sooo any help before i head back off to the mech would be much appreciated and save me alot of money,

Thanks guys.

Big Rig · 25-07-2010, 11:03 PM

I would start with bleeding the master cylinder and work my way down the rear brake line to the back of the car. If your not getting fluid out at the rear calipers lock off the bleed valves and go back to the front. Top up the master cylinder remove the line for the rear directly at the master cylinder. Hold your finger over the port and have someone press on the pedal. If you get fluid there then go to the next position further down the line checking for kinked or damaged brake lines as you go. It could be any number of things but if you follow the above (which is what your mechanic should be doing) you will find the problem.

Grumpy · 26-07-2010, 05:41 AM

Ist thing I would be doing is get a new Mechanic, shockers don't have anything to do with brakes! Firstly which discs had the oil or fluid on them front/rear left or right side.

croozza · 26-07-2010, 07:19 AM

Are the rear flexible brake lines twisted, very easy to do and will cut any fluid to the brakes.

stoneddoodle · 26-07-2010, 06:03 PM

Quote:

Originally Posted by Grumpy

Ist thing I would be doing is get a new Mechanic, shockers don't have anything to do with brakes! Firstly which discs had the oil or fluid on them front/rear left or right side.

Sorry grumpy i was in such a rush to write the post out i got a bit jumbled up. It was a figure of speech " the brakes are acting as if there is oil on the disks" the reason the mech had me change the shocks was because of the car dipping to one side when braking. the rear pass side shock was stuffed and the front driver side also, sooo to elimate the poor brakeing this needed to be sorted first. Sorry haha

stoneddoodle · 26-07-2010, 06:06 PM

Quote:

Originally Posted by croozza

Are the rear flexible brake lines twisted, very easy to do and will cut any fluid to the brakes.

Yeah there fine mate, this is really getting to me and my poor pocket haha, its seems as if most of the braking power is happening through the front drivers side wheel the car dips alot to that side when braking and i have had all the suspension changed soo i know its not that. I when on some mud and sure enough just the fronts lock up and no rear braking effort at all either side.

Thanks guys

cloughcarib · 26-07-2010, 09:35 PM

Have you or you 'mechanic' stripped down the master cylinder since the problem started? There is a small chance that something was forced through .
Do you have a compressor?
Remove the rear brakeline from the master cylinder, open the bleed valve on one wheel and put a bit of low pressure air from the wheel towards the master cylinder. Have someone see if there is evidence of air coming back through(tell them not to stand too close and have a rag handy).
If the air comes through freely, then there's no blockage. If it's restriced or does not come through at all, then cover the master cylinder end completely with the rag, tell everyone to stay out of the way, and give it a strong blast.
If nothing else, this wil let you know if the line is blocked.

croozza · 27-07-2010, 07:25 AM

Quote:

Originally Posted by stoneddoodle

Yeah there fine mate, this is really getting to me and my poor pocket haha, its seems as if most of the braking power is happening through the front drivers side wheel the car dips alot to that side when braking and i have had all the suspension changed soo i know its not that. I when on some mud and sure enough just the fronts lock up and no rear braking effort at all either side.

Thanks guys

sounds like it is the rear proportioning valve, have you checked that yet, if so check again, it may just need adjustment. You could even try and put a heavy load in the back and see if it brakes better or not.

Grumpy · 27-07-2010, 10:07 AM

Sounds like a crushed line or blocked valve or something along those lines if you cant get fluid to the rears.

Grumpy · 27-07-2010, 10:12 AM

Had a very similar problem with mine but was really nothing to do with the brakes, the wheel bearings on one wheel had worked it's way loose and caused the brakes to think they were on because of the sideways movement on that wheel, sometimes made me wonder if I had brakes at all. Go figure it surprised me.