Handbrake adjustment and thoughts.....

[andywood]

Adjusted mine again today as was starting to get a little too close to the roof!

Have had the seats out in the past, but realised today that this can be done with the seats in the fully forwards position on the sliders and getting access to front centre console screws by squashing down the seat bolster. My seats are cloth so not sure how easy this would be on leather, but saved me loads of time and was v easy.


Doing the handbrake adjustment got me thinking though as the threaded end of the cable is now getting increasingly long - where does it stop?? Has anyone ever bottomed out the thread?

Some of the increase in travel I thought is due to wear of the rear pads, but is this really the case, and most I assume is due to the stretch/play in the handbrake cable? From what i can see no adjustment can be made at the caliper end of things either.
I am just not sure what you can do about the cable side of things as changing out pads when they are low (and mine aren't) is not going to have a major impact on the cable travel.

Any thoughts or am I just thinking too much??!

Andy

[Anonymous]

Found the handbrake adjustment on mine gained a lot more adjustment on the cables once the sliders were freed off on my callipers and I never take the seats out of mine to adjust, all I use is a 1/4 drive deep socket with ratchet an long extension and a bit of blue-tac.
 
Pop the blue-tac in the socket, take the lock nut out (the blue-tac stops it falling into the depths of never to be found   s:wink: :wink: s:wink:  )
Slacken the bottom nut right off.
Check the free movement on the pivots at the wheel end.
Pump the brakes (with the engine running) a few times.
Adjust the nut as necessary.
Pop the lock nut in with blue-tac again and tighten.
If it turns the bottom nut just remove the plastic U shaped thing and wangle an open ended 10mm in their to hold while locking up.

[frogger]

If your using the handbrake end to adjust up cable slack routinely, then chances are the piston is too far away from the pads 'at rest', unless the cable is truly stretched, which i doubt. You need to adjust the piston travel correctly to the current pads and then re-adjust the handbrake from there.

Use Paul Woods guide in this link:  m http://www.imoc.co.uk/forums/viewtopic.php?t=4945 m

There is no other way with MR2 calipers (any year, mk1's, mk2's and mk3 roadsters - all use the same caliper pretty much).

If you follow the above guide whenever you replace the pads, you should find that adjustment at the handbrake end ends up pretty much the same as it did last time you fitted new pads - with no rapidly decreasing available thread!

[andywood]

Wow, thanks for that. Is the first time I have read about the need to wind back out by 180deg after doing a wind-back tool job on the rear caliper.
Maybe a mod on here needs to add a note to either the rear disc/pad replacement thread or the handbrake adjustment one, seems pretty key if it is needed to reset the handbrake mech in the caliper itself.

Did my rear discs and pads a while ago and used a wind-back tool prior to aligning the pad stud with the slot in the piston head, pretty sure that I wouldn't have come out by 180degrees so maybe that explains the handbrake situation.

Would it make the handbrake less effective as well as more travel? I can't see why it would.

I am just going to leave it until the next pad change or alternatively if the handbrake becomes unbearable - any problems in leaving it do you think? Again, I can't see why there would be, but doesn't harm to ask for a second opinion  s:wink: :wink: s:wink:  

Cheers

Andy

[frogger]

If it holds the car securely on steep slopes okay at the moment, then you should be okay to leave it i guess!

Definitely required when replacing rear pads though.

Just had a look at the guide in the 'How To' section, and you're right - it does just need a one-liner adding in about rotating pistons back out 180 degrees.

It's not often spoke about, and not commonly practiced even at many garages, because as far as anyone cares they [usually] end up with a handbrake that seems to function perfectly well doing it the 'normal' way - so why the concern.

Well for any doubters, if you read exactly why its required in Pauls original post ( m http://www.imoc.co.uk/forums/viewtopic.php?t=4945 m ) and the endless debate on the issue in a subsequent thread ( m http://www.imoc.co.uk/forums/viewtopic.php?t=6372 m ) its clear why it should always be done   s:wink: :wink: s:wink:  

Just found my original post on this topic too if its of any use :  l viewtopic.php?f=11&t=30306#p370855 l

[andywood]

This is the hard part of trying to guess what is good or not based only on my car!!

It passed the mot ok (way after I had changed discs and pads) but i do have to really pull hard on the handbrake to get it to hold on a moderate slope, I steer well clear of parking on steep slopes (handbrake wouldn't hold the car to pull away on steep mountain roads in scotland)!
Both rear wheels definitely bind on the handbrake as I have checked them jacked up.

Seems like loads of people on here also complain of poor handbrake performance (compared to other cars), is this just a 'feature' of the mr2 or are loads of us suffering from ill-fitting of pads in the past??

I am off to the alps on sat am which will no doubt need some parking on more than a moderate slope - am tempted to get it all off and re-fit existing pads, but worried that I will get a problem that will risk me going or cause loads of stress!
Just think best to leave as until I am back and have time to really do it properly.

Andy

[frogger]

I would be tempted to give them a go before you head off if you have time, purely because it's not holding on a steep hill now (which it absolutely should if it was working 100%).

There's really no reason why you should encounter any problems when redo'ing them though, so I wouldn't worry too much.
Plus if there are any problems - better to find out!

Of all the roads in the world to be heading to with handbrake issues, it had to be the alps (!)   s:lol: :lol: s:lol:

MR2's in general have always suffered a bit with rear brakes... I'd say half the time its because of seals being old and knackered, which combined with the lower-than-average milage many MR2's see results in a little bit of rust taking hold of the moving parts (and it doesn't take much to cause sliders or pistons to bind). The rest of the time its probably due to fitting issues, such as incorrect handbrake adjustment, be it at the piston end, or the lever end.

[Anonymous]

Wow, thanks for that. Is the first time I have read about the need to wind back out by 180deg after doing a wind-back tool job on the rear caliper.
Maybe a mod on here needs to add a note to either the rear disc/pad replacement thread or the handbrake adjustment one, seems pretty key if it is needed to reset the handbrake mech in the caliper itself.

Did my rear discs and pads a while ago and used a wind-back tool prior to aligning the pad stud with the slot in the piston head, pretty sure that I wouldn't have come out by 180degrees so maybe that explains the handbrake situation.

Would it make the handbrake less effective as well as more travel? I can't see why it would.

I am just going to leave it until the next pad change or alternatively if the handbrake becomes unbearable - any problems in leaving it do you think? Again, I can't see why there would be, but doesn't harm to ask for a second opinion  s:wink: :wink: s:wink:  

Cheers

Andy

Just replaced all discs & pads on my car and as with the first time all I did was wind the pistons back, put the pads in & re-assemble, never wound them out at all, each time the auto adjusters did their job and the handbrake works perfectly.

[frogger]

I can understand your scepticism. I'm well aware that you can end up with a handbrake that performs its function without doing this step.

In one of the links in an earlier post ( m http://www.imoc.co.uk/forums/viewtopic.php?t=6372 m ) imoc user "lower" makes the exact same point as you, and Paul Woods/Woodsport explains in detail (many times!) the principle behind why it is required.

I'm not going to bother trying to push the point - It's been done to death on tother forum

As I see it, why wouldn't you?  s:) s:)  You're in there anyway with the winder tool when replacing your pads - so whats the harm in spending an extra 4 seconds winding it back out 180 degrees or so.

It's up to the person doing the job at the end of the day - Don't do it if you don't want too  s:) s:)

If you take it to an MR2 specialist they will do though (or should do) and I can guarantee I will be too  s:wink: :wink: s:wink:

[andywood]

This is a nightmare trying to judge what is good or bad, is it really that black and white if it is functioning correctly or not?? (this really isn't the silly question that it sounds like!!)

Took the car out tonight for the fun task of holding the car on slopes with handbrake (as driveway is flat!), this re-confirmed as I already knew that on a half decent slope with the handbrake jammed on to the last click, it only just holds the car and doesn't stop it from moving if the car is not stationary.

I know I should stop jabbering on and just get to work on the car to see if the wind-back-out-thing will fix it, but I just don't want to find out that I get no improvement after taking a half day off work days before I head off on hols in it.

Final decision needed.........

Andy

[frogger]

One things for sure from the above description - pulling the handbrake all the way up isn't clamping the pads firmly to the disc.

The only resolution for this is either

a) adjust even more at the lever end.
Or
b) wind the piston out to meet the discs.

There is a 3rd very unlikely situation - that your cables are stretched to buggery! Cross that bridge if you come to it though.

You'll be surprised how little any MR2 piston actually moves when you pull on the handbrake; because of this if the pistons are too far away the handbrake movement just won't give enough travel to firmly clamp the pads against the disc.

If you get on it tomorrow once your back from work, you should have at least a couple of hours of daylight left to check them, and save a half day of valuable holiday  s:D s:D

If off to check my fronts now - started clunking when I brake, think a clip has slipped out.
Hoping to get that done before its properly dark with 40mins or so left. With a couple of hours to spare you should be okay.

[andywood]

Cheers for the further food for thought......

a. adjusting at lever end won't resolve it as this will only take up any slack and not actually apply more load to piston/pad/disc. I also did this at weekend which reduced travel on lever but did not improve handbrake performance.

b. pistons must be in contact with disc as handbrake is working, just not as well as I would expect and not as other cars i have had. More movement of piston is not really possible if it has contact, it is then all about the amount of load applied to the piston to clamp the pads - this is why i thought that the auto adjust handbrake mech in the caliper must be engaged as otherwise I would have jack-all handbrake action. Thus i just assumed it was a generic poor mr2 handbrake thing going on. Rear brakes also working ok from a foot-pedal point of view which also suggests that the piston is correctly positioned to actuate when needed.

c. stretch - doubt it very much based on mileage of car, how it is kept (brake on lightly) and that i would probably be able to feel this on handbrake application. When the brake is applied and starts to bite I struggle to then get more than a couple of clicks which suggests stretch is minimal.

Hope you fix yours, seems i have to just settle this debate in my mind and sleep easy when away by getting an early finish tomorrow and getting the swear-box out  s:wink: :wink: s:wink:  

Andy

[frogger]

Agree with you entirely on points (a) and (c) - not sure what I was thinking when suggesting option (a) - Moment of madness!   s:) s:)  

With (b) though, piston adjustment might make a difference I think. The piston may be in contact, but I bet if you watch what happens to the piston when you pull the handbrake lever it will not be moving the piston the full travel you would usually get with a properly adjusted mechanism (though as mentioned in my previous post, the 'proper' amount of travel is still a tiny amount of travel!).

Unfortunately you wouldn't be able to test this without removing the caliper body though   s:| :| s:|  

I'm struggling to think of any other reasons why it wouldn't be working well, other than the caliper internals needing attention, which I havent really heard of before. Only really seen any internal handbrake components removed to replace seals when doing a complete caliper overhaul.

[Anonymous]

You have made sure your sliders are free?

It was only when one of my pads went down to metal and I replaced everything I found the sliders were well seized, prior to that I had the same issues with my handbrake, even with constant adjusting it was terrible but everything seemed to be working fine.

[andywood]

Some headline conclusions after finishing work a few hours early today:

1. Frogger - you're a legend, thanks very much for the info and persisting in getting me to do it  s:wink: :wink: s:wink:  

2. MODS - you have to get this on the 'How To' sticky for changing the rear discs/pads

3. Everyone who has not got very good handbrake performance - DO THIS NOW!


So in more detail then.
New rear discs and pads approx 5000miles ago, followed how to on here and no probs whatsoever with braking performance. Handbrake has always been suspect, but passed MOT ok and would normally hold in most situations with a good yank. Now the handbrake is fantastic, holds on all steep hills and pulls the car to an abrupt stop if moving.

Got the car up and wheels off and had a look at the handbrake cable linkage (h/brake on and nothing yet adjusted), the linkage cam was clearly at full extent and had nothing more to give.
Handbrake off, cable fully slackened off at h'brake lever end and then took off calipers. Wound the pistons back in as far as possible and noticed that they never actually stop turning but will no longer actually move in (this I assumed was min position). Then wound out the prescribed 180deg (whilst ensuring pad lug was in-line with piston recess) but would not allow me to then re-fit the caliper as discs and pads still fairly new.
I tried loads of times but it was not going to fit after 180deg off piston moving out, i had to settle for approx 120deg. Same on both sides, re-assembled, pumped foot brake to set everything, set handbrake cable (now with lots less slack in it) and noted that the h/brake linkage cams were in a much better looking position on both sides with the h/brake. Road test confirmed all was greatly improved, smiles all over me face, now supping on a nice cold beer.
Oh yeah, re-checked wheel nut torques after road test (twice)  s:wink: :wink: s:wink:  

If you do not wind-out then I am sure you could be lucky and handbrake mech adjusts ok, but there is clearly a risk that it will not as I find out the hard way.
I expect that 180deg of wind-out is needed to guarantee all is good but my 120deg-ish achieved it on both sides which may be because i had them fully wound in.
Am not going to start a debate on what wind-out is needed, but once they had gone through 90deg or so you could actually feel more bite/resistance in turning the piston, maybe this is everything getting engaged and aligned as it should.

Also seem to have better footbrake as a secondary benefit, may just be my imagination as Paul on imoc mentioned that improvements could be expected to normal car braking as well.......

....anyway, I am well happy with the result, cheers again

Andy

[frogger]

Glad to hear it's all sorted   s:bounce: :bounce: s:bounce:  

I'll adjust my previous posts to 180*-ish incase anyone uses them for reference lol