Help please on rear brakes....

#21
harveyp6 said:
Was any work done to the rear brakes prior to the MOT? If so I would say that at the time the MOT was done, although the brakes worked well enough to pass the test, they were not correctly set so as to allow the mechanism to self adjust from that point onwards, and now that the pads have worn down a bit with use neither the hand or footbrakes are working because the pads are too far away from the discs.The hydraulic piston will be right up against the stop washer.
Otherwise it looks as though you'll have to try setting them up properly, and see what (if any) faults you find along the way.
The only thing done prior to the MOT was to free up the seized handbrake linkage.

You say "...they were not correctly set so as to allow the mechanism to self adjust from that point onwards..."

and "...Otherwise it looks as though you'll have to try setting them up properly..."

How is this done? The Haynes is completely elusive in this respect.
 

harveyp6

Well-Known Member
#22
I can only tell you the way I would do it. (Other methods are available......Allegedly)

Firstly I would check to see how much movement there is on the inner pad each side with the handbrake off. Then if I suspect, there is too much, remove the rear discs and both linkage clevis pins from the caliper quadrants. Remove the two bolts on the diff for the handbrake compensator mechanism and move it out of the way. Then manually operate the quadrants until with them at rest back on their stops, the disc just slides in. Then refit the cable and adjust it so there is no slack, but the quadrants remain on their stops. If the inner pads don't move out when the quadrants are operated, then the calipers need to be removed and dismantled to find out why.
 
#23
harveyp6 said:
I can only tell you the way I would do it. (Other methods are available......Allegedly)

Firstly I would check to see how much movement there is on the inner pad each side with the handbrake off. Then if I suspect, there is too much, remove the rear discs and both linkage clevis pins from the caliper quadrants. Remove the two bolts on the diff for the handbrake compensator mechanism and move it out of the way. Then manually operate the quadrants until with them at rest back on their stops, the disc just slides in. Then refit the cable and adjust it so there is no slack, but the quadrants remain on their stops. If the inner pads don't move out when the quadrants are operated, then the calipers need to be removed and dismantled to find out why.
Then I guess it's calipers out anyway, since the pads don't even move when the footbrake is applied.
 

harveyp6

Well-Known Member
#25
Not necessarily, if it's way out of adjustment then it's possible that the pads won't move. Dismantle it as far as I said, then check to see if it ratchets up, if so set it up properly, if not remove the calipers.
 
#27
HarveyP6,
Do you have pictures of a later rear caliper than Malcolm found?
The article resulted from Malcolm's findings with rear calipers that reached these shores. The company stopped importing P6 Rovers into North America in early 1971. That's all we have. If you are willing to add to what we have, we would appreciate it.

Although we would try to rebuild with the latest version of parts, the Rover owners outside of mainland Britain have to do what they can with what they have. :)

Eric
 

harveyp6

Well-Known Member
#28
I've not got any pictures I'm afraid, and even if I had my computer skills aren't up to much. It's a shame because "TheRoveringMember" recently stainless sleeved his rear calipers, and pictures could have been taken of those during reassembly, and with his superior computer skills he could have got them to you. Having said that, with the number of cars that he has, there will be another pair along shortly........ :lol:

I know what you mean about having to make use of what you have in your situation. It won't help you to know that I had a 2 gallon bucket full of late caliper internals that went into the scrap due to lack of space, and seeing as I wasn't doing a good few calipers a week at the time I didn't see the point in keeping them in pre-internet days.
 
#29
Well, I do have the calipers that the stainless equipped ones replaced (though they're earlier if I'm correct) which I could deliver to Harvey to dis-assemble while I take pictures of him in his natural habitat doing what comes naturally to him. Stripping Rover things down to their component parts resulting in a pile of bits which only he can make sense of (I think he's trying to refill that 2 gallon bucket :wink: ).
We'll try & arrange something. This pair also needs to be re-sleeved & yes, I do have a car waiting for them among other jobs she needs. The Denovo.
 
#30
Any willingness to upgrade the RCCC article on rear brakes would be gratefully appreciated by all who need free information, often not available in official manuals. All credit will be given, of course. :)

Send pictures or text to:
p6rovers@yahoo.com

Eric
 
#31
First of all, thanks for all your help!

I completely dismantled the rear brakes and found the following faults:

- All four brake pads worn to a different degree, from almost new to being smack at the metal backing plate.

- Brake discs hardly worn, obviously the rear brakes didn't work for a LONG time.

- Outer brake pads wrong type.

- Handbrake quadrant seized on one side.

- Handbrake mechanism severely tampered with.

- Adjusting mechanism seized in one caliper, incorrectly assembled in the other.

- Both brake pistons at the end of their travel.

- Internal leakage in both calipers.

- Flexi pipes clogged (I'm NOT kidding!).

Since this is now the second time I did a complete overhaul of the rear brakes, I feel confident enough to write a tutorial, which I will do once I can allocate the time. The very helpful article on the club website can then be amended with it if you like. There are a few potential pitfalls I experienced twice now, which I will point out.

I can only recommend to all of you: Inspect and maintain the rear brakes at least once a year. If they aren't neglected, they are actually quite easy to work on, hence I don't understand why they are so dreaded and often left to rot. I went through the whole shebang on both P6es I bought, hence I would say, factor a rear brake rebuild into your budget every time you buy one. The requird parts will cost you around 120£ if you don't need discs or actual caliper hardware.
 
#32
Junkman said:
First of all, thanks for all your help!
<SNIP>
Since this is now the second time I did a complete overhaul of the rear brakes, I feel confident enough to write a tutorial, which I will do once I can allocate the time. The very helpful article on the club website can then be amended with it if you like. There are a few potential pitfalls I experienced twice now, which I will point out. </SNIP>

Junkman,
Your experience would certainly add to the informal "after-manual" information which we would like to post under "Practical Tips" on the RCCC website: http://www.roverclub.ca/practicaltips.htm

Eric :D
 

cobraboy

Well-Known Member
#34
every year I have to battle with rear brakes and scrape through an MOT if lucky. wondering theres alternatives ? not e type jag though
It really should not be that way, the brakes are more than capable. In testing for my braking woes I found pulling the handbrake on hard at 50 mph would lock up the rear end.

I would gather as much info as you can on setting them up, take them off, spend some time making sure everything is perfect with new seals, manually operating the handbrake mechanism to make sure the large piston ratchets out, then re fit.
The handbrake quadrants need to be on their stops when at rest, then take the slack out of the cable keeping the quadrants on the stops.

I ratchet out the pistons manually when the calipers are fitted, I found I did not need to remove a disc to get the adjustment right, it came good anyway.

Perhaps your calipers are not put together correctly internally ?
 
#35
before I swapped rear callipers for exchange units (Wins International) I stripped both to check internals .( slight corrosion and pitting ) using a kit bought online for new rubbers .seal etc and was VERY careful to observe way the 'pin' went back in on reassembly. aware it was often not in place and fell on side thus making hand brake ineffective. as no difference was found when back on car ( rubbish handbrake) replaced both callipers ! no change.. new discs and pads. handbrake cable . removed cable and checked. handbrake mechanism .refit cable checked pads. slippers. fully wound back . cable. slack etc and everything I could think of or suggested by others . car still has a handbrake that is about as effective as throwing a pack of butter out of car window on a piece of string. bear in mind I had once owned a MK 4 for Zephyr V6 ( circa 1970's) with essentially same calipers ..they were activated by handbrake pulled from under dashboard and were very very effective . easily holding a very large heavy car on a steep hill. my current Rover I would not trust to stay still on a 2" incline. I did try a handbrake in another rover P6 V8 at a show . hand brake was far better .. though when fully fully on was uo at rather a steep angle.wondering if mine is simple set up wrongly but cannot see where its wrong! slack in cable is about 15mm ( 2" pull on handbrake before biting) . oh well nobody. can offer a fix. and sadly have not yet found a car I can swapo rear brakes with ? ( maybe a ford Zephyr ?)
 

harveyp6

Well-Known Member
#36
Can you post pics of both calipers looking from the front of the car, showing the position of the quadrants, both with the handbrake OFF, and then with it ON. Also when under the car with the handbrake OFF (with caution obviously) reaching over the propshaft, how far down can you pull the handbrake cable before the quadrants start to move?
 

chrisw

Well-Known Member
#37
Can you post pics of both calipers looking from the front of the car, showing the position of the quadrants, both with the handbrake OFF, and then with it ON. Also when under the car with the handbrake OFF (with caution obviously) reaching over the propshaft, how far down can you pull the handbrake cable before the quadrants start to move?
And a picture of the handbrake lever with everything fully engaged.. wondering if there is too much slack in the cable, and the lever is trying to take off into space!
 

chrisw

Well-Known Member
#39
will try and get under car over Ams for pic. handbrake movement is in fact limited and cant get tulles past about 4 clicks.. unless your name is the incredible hulk!
Four clicks sounds like it is adjusted correctly.. however, it would be interesting to see how much movement that generates on the calipers, and how much travel there still is after the handbrake is locked on.

Unless I've missed it; have you jacked up the back end, put the handbrake on, and checked to see whether it's one or both of the rear wheels still turning?
 
Top