AntonUK
|
| posted on 13/2/16 at 08:53 PM |
|
|
Sierra Rear Calipers
Hi All,
I have a pair of sierra rear calipers on my Ginetta G27 (live axle) and I appear to have got in a muddle with getting them setup correctly.
We had to adjust the handbrake cable this afternoon, but struggled with it not releasing once the handbrake was lowered. After some reading it looks
like there is a specific order in which to fit the new pads to ensure the self adjusting mechanism works correctly. I'm going to start again
tomorrow and purchase a rewind tool etc. Before I risk cocking it up again, I have a couple of questions...
1. Does the little bump/nipple on the rear of the pad have to be aligned with the cut out in the caliper piston?
2. A previous post says if not done correctly it can knacker the self adjusting mechanism, is there a way of testing if I already have or will it
reset once rewound again?
Cheers as always.
Build Photos Here
|
|
|
|
|
JAG
|
| posted on 13/2/16 at 10:13 PM |
|
|
OK
Follow the recommended method to set these up and they'll work fine. They can be a bit awkward to bleed especially if they're mounted
upside down (some are on kitcars). The bleednipple should be at the top to bleed properly.
1) The little pip on the back of the pad does locate in the slot in the piston. Simply rotate the piston until it slots in. The pip stops the piston
from rotating while in use. Rotating will cause the self-adjusting mechanism to de-adjust.
2) You can't bust the self-adjusting mechanism that easily. It's tough as old boots.
I worked for Lucas when we designed this caliper 
[Edited on 13/2/16 by JAG]
Justin
Who is this super hero? Sarge? ...No.
Rosemary, the telephone operator? ...No.
Penry, the mild-mannered janitor? ...Could be!
|
|
|
adithorp
|
| posted on 14/2/16 at 12:09 AM |
|
|
Yes, the pip should locate in the piston slot.
Ensure that the cable is allowing the levers to return all the way to the stops. Wind the piston fully in and until the slots line up at the 12/3/6/9
o'clock positions (so they line up with the pip). Reassemble and then use the pedal to pump the piston fully out BEFORE operating the hand brake
lever. Adjust the cable but ensure the levers fully return to the stops or the adjuster won't work properly. If the lever is operated before the
pistons have been pumped out it can damage the adjuster mechanism.
"A witty saying proves nothing" Voltaire
http://jpsc.org.uk/forum/
|
|
|
AntonUK
|
| posted on 15/2/16 at 01:55 PM |
|
|
Perfect, thanks both.
Have picked up a rewind too today, will give it another go this evening.
Build Photos Here
|
|
|
AntonUK
|
| posted on 15/2/16 at 09:54 PM |
|
|
So I refitted these correctly this evening. I ran into a problem where the 2nd calipers would not rewind. Found the issue to be hydraulic, I released
pressure by opening the bleed nipple and then it went back together perfectly. But...
After pumping the pedal up the calipers have locked the wheels, only way to release them is by cracking a bleed nipple. Same goes for the handbrake
put it on and it is still locked up after release.
I did find that is I opened the connection pipes (calipers side) to the bias valve the handbrake would release when dropped.
Any ideas? I'm guessing the either the fluid isn't returning to the master or I have knackered the self adjusters.
Build Photos Here
|
|
|
adithorp
|
| posted on 15/2/16 at 10:47 PM |
|
|
Strange one. Not a knackered adjuster symptom I've come across (usually just get either excess lever travel either straight away or OK then gets
worse as the pads wear). Sounds more like the pedal push rod not having any play in it at rest. That causes the brake to hold residual pressure and
stick on... but wouldn't account for it sticking on after just the h/brake is pulled.
"A witty saying proves nothing" Voltaire
http://jpsc.org.uk/forum/
|
|
|
AlexXtreme
|
| posted on 16/2/16 at 08:36 AM |
|
|
Hi Anton / All,
What are the callipers on your car? I have the same set up on my G27 with a live axle and I am pretty certain that one of them is partially seized.
Previously I have to take a calliper off and taken it to the local motor factors and tried to find a match :-)!
Cheers
Alex
|
|
|
AntonUK
|
| posted on 16/2/16 at 04:13 PM |
|
|
Mine are off a Sierra.
One thing I do know about mine are they they are not siezed, the move quite freely.
Build Photos Here
|
|
|
AlexXtreme
|
| posted on 16/2/16 at 04:20 PM |
|
|
Mine are Sierra as well just don't know which model :-(
Alex
|
|
|
AntonUK
|
| posted on 16/2/16 at 07:10 PM |
|
|
as far as i know there is only one... if not I've been very lucky with spares and pads
Build Photos Here
|
|
|
AntonUK
|
| posted on 16/2/16 at 07:12 PM |
|
|
Update regarding the locking issue.
Ive removed the bias valve and replaced it with a straight throgh connector.
The handbrake now works fine, and releases correctly. Just have to wait until Thursday before I can bleed the system and re-try the foot brake.
Build Photos Here
|
|
|
