Technical Disc brake handbrake mechanism

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Technical Disc brake handbrake mechanism

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Nov 16, 2018
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chesterfield
would any of you guys know if the handbrake mechanism can be taken apart for cleaning/servicing?
handbrake not fully releasing on the left rear, unless I get dirty knees and manually give the lever on the calliper a tug.
the attached pictures show how the right side goes all the way to the stop, where the left gets caught up.
cables have been checked and are nice and free, a bit of penetrating oil frees it up for a few days, but then attracts all the dirt and gets jammed up again.
 

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I suspect you might have some corrosion that's stopping the spring pulling the arm fully back.
The near side does tend to pick up more water due to the road camber and that one looks more rusty then the offside.

Before going any further, I would remove the cable and try operating the arm, rule it out once and for all.

Then remove the caliper from the carrier and check the pins in the carrier are free, if they are jammed the caliper can't float and center it's self and you'll end up with a similar problem.

Other than that, it could be the cam that rams up the piston or the piston it's self has corrosion.

My bet is the carrier pins are seized up.
 
I suspect you might have some corrosion that's stopping the spring pulling the arm fully back.
The near side does tend to pick up more water due to the road camber and that one looks more rusty then the offside.

Before going any further, I would remove the cable and try operating the arm, rule it out once and for all.

Then remove the caliper from the carrier and check the pins in the carrier are free, if they are jammed the caliper can't float and center it's self and you'll end up with a similar problem.

Other than that, it could be the cam that rams up the piston or the piston it's self has corrosion.

My bet is the carrier pins are seized up.

slider pins are all good, replaced them and the pads back in April as they were sticking, although one pin has a nylon sleeve and is still a little stiff.
foot brake seems to release fine, so narrowed it down to dirt or corrosion on the handbrake mech

I was interwebing until 1am trying to find a video or diagram of how its assembled, but no luck so far
 
The handbrake arm is removable, I took mine off to spray the callipers. :D
Simply undo the 13mm nut making sure you know how the spring attaches and it should prise off, there is a seal behind it to stop any fluid escaping, then give what was behind the arm a clean, put the arm back on and check it's operation.:D
 
If the hand brake thread is wound out too far, you cannot easily fit the hand brake cable. Wind the piston in a bit, fit cable and wind it back out to fit over the brake pads. This has to be done if the pads are part worn but adjustment can be needed with new pads.


I attempted to rebuild my caliper, bought an axle set seals and pistons kit. Removed the hand bake levers, cleaned and painted. Sadly gave up because I could not extract a circlip down the bottom of the hydraulic cylinder. The brake bled just fine, BUT driving the car, brake fluid PI$$ED out of the hand brake spindle. I had clearly damaged the seal or something.

The replacement caliper is a Pagid. Cost is about £100 from Euro Car Parts after the old part is returned. Onine sellers are a chunk cheaper. BUT the Pagid is very well made - it looks brand new. I think better to get the top spec rebuilds.

Pagid Left is 76469
Pagid Right is 76470

www.buycarparts.co.uk have lower cost calipers. I cant vouch for their service as I needed the caliper quickly so had to pay the premium.
 
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The handbrake arm is removable, I took mine off to spray the callipers. :D
Simply undo the 13mm nut making sure you know how the spring attaches and it should prise off, there is a seal behind it to stop any fluid escaping, then give what was behind the arm a clean, put the arm back on and check it's operation.:D

I did loosen that off before but the lever stayed firmly attached, probably all the crap holding it together. Ill give it some wd40 and good persuading over the weekend.
 
If the hand brake thread is wound out too far, you cannot easily fit the hand brake cable. Wind the piston in a bit, fit cable and wind it back out to fit over the brake pads. This has to be done if the pads are part worn but adjustment can be needed with new pads.


I attempted to rebuild my caliper, bought an axle set seals and pistons kit. Removed the hand bake levers, cleaned and painted. Sadly gave up because I could not extract a circlip down the bottom of the hydraulic cylinder. The brake bled just fine, BUT driving the car, brake fluid PI$$ED out of the hand brake spindle. I had clearly damaged the seal or something.

The replacement caliper is a Pagid. Cost is about £100 from Euro Car Parts after the old part is returned. Onine sellers are a chunk cheaper. BUT the Pagid is very well made - it looks brand new. I think better to get the top spec rebuilds.

Pagid Left is 76469
Pagid Right is 76470

www.buycarparts.co.uk have lower cost calipers. I cant vouch for their service as I needed the caliper quickly so had to pay the premium.

Last resort would be replace the lot, id much rather repair and learn a few things along the way....then fail, swear alot and replace anyway ?
Lokking through the paperwork i got when i bought the car, the right caliper was replaced october 2017, i bought car the following august, its had a good chunk of money thrown at it in the past.
 
Last resort would be replace the lot, id much rather repair and learn a few things along the way....then fail, swear alot and replace anyway ?
Lokking through the paperwork i got when i bought the car, the right caliper was replaced october 2017, i bought car the following august, its had a good chunk of money thrown at it in the past.

That's my way. After all, how hard can it be to rebuild a single piston brake caliper? I'd say slacken the piston away from the pads. The cable should fit easily. Then wind up the piston to meet the pads. Do both sides to the same clearance and see how the lever feels.
 
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