MR2 Roadster Owners Club

The Workshop => Maintenance, Problems & Troubleshooting => Topic started by: ad_car_08 on July 17, 2009, 22:04

Title: MOT failure - Handbrake
Post by: ad_car_08 on July 17, 2009, 22:04
OK, so I've now put my car through an MOT...was about to pass with flying colours it it wasn't for my flaming handbrake!  s:roll: :roll: s:roll:  

According to the MOT tester, it passed on handbrake performance, but failed because the drivers side was reading 161kg pressure, but the passenger side a measley 51kg!
Diagnosis from the MOT tester is a sticky brake caliper or maybe a sticky brake pad.

I suggested applying copper grease to the slide bar to help the caliper slide/free it up, but he didn't think that would work. I also suggested adjusting the handbrake cable to which he replied loosing the handbrake and pumping the footbrake to readjust it *might* work, but again doubtful.
HIs money was on the caliper, or more specifically the "swing arm" that pushes the piston/caliper on when applying the handbrake, but as its a "specialist" problem, they couldn't fix it there (which kinda reassured me that he wasn't touting for business like i first thought they might - see my MOT post) because you can't fix calipers apparently?? have to get a new/reconned item??

Was just wondering if anyone out there has experienced the same problem and how you fixed it??
Title: Re: MOT failure - Handbrake
Post by: rmowbray on July 18, 2009, 00:41
The other common problem (and much cheaper than a caliper) is a sticking handbrake cable.

Visual inspection with the wheel off should allow you to see in the cable is stuck, (compare one side to the other).
Title: Re: MOT failure - Handbrake
Post by: Anonymous on July 18, 2009, 05:27
This may be usefull if its worst case.
 m http://cgi.ebay.co.uk/Toyota-MR2-1-8-Br ... 3:1|294:50 (http://cgi.ebay.co.uk/Toyota-MR2-1-8-Brake-caliper-repair-kit-R-4533_W0QQitemZ310127588342QQcmdZViewItemQQptZUK_CarsParts_Vehicles_CarParts_SM?hash=item48350b73f6&_trksid=p3286.c0.m14&_trkparms=65:12%7C66:2%7C39:1%7C72:1121%7C293:1%7C294:50) m
Title: Re: MOT failure - Handbrake
Post by: wbarrwebster on July 18, 2009, 09:11
Hi,

Had the same issue 2 years ago, not uncommon as has been said,
First things fist.......try adjustment first........ search previous "How To" threads....then go from there

B
Title: Re: MOT failure - Handbrake
Post by: ad_car_08 on July 18, 2009, 12:56
Brilliant, thanks, I'll try that and might be back to ask what to try next   s:oops: :oops: s:oops:
Title: Re: MOT failure - Handbrake
Post by: ad_car_08 on July 21, 2009, 10:05
Right, I followed the "How to" on adjusting the handbrake cable (an invaluable source & made the process a doddle!).

In both pictures I'm sitting in the drivers seat - so here's what I saw when I loosed the handbrake cable fully....

(http://farm4.static.flickr.com/3469/3736936992_d399f3353b.jpg?v=0)

and then after adjusting/pumping the footbrake/pulling the handbrake on a few times etc....

(http://farm4.static.flickr.com/3488/3736930062_23fd9213a7.jpg?v=0)


As you can see, the shiny metal bit in the middle is definitely not level, which explains why the passenger side isn't pulling on quite as firmly as the drivers side (which caused the car to fail its MOT)

Have any of you folks been in this situation and have any words of encouragement or suggest what could be done?
Does this part need to be substantially lubricated (seemed pretty dry to me)?
Is this a sign of something i.e. uneven pad wear or does it back up the mechanics hunch about a sticky caliper? It's obvious from the picture that something appears to be sticking....  s:? :? s:?
Title: Re: MOT failure - Handbrake
Post by: ad_car_08 on July 21, 2009, 10:12
(Why aren't my pictures displaying?! I've wrapped the html in the "[img]" tags)
Title: Re: MOT failure - Handbrake
Post by: Peter Wright on July 21, 2009, 10:14
Quote from: "ad_car_08"(Why aren't my pictures displaying?! I've wrapped the html in the "[img]" tags)
Bring flicker up, right click the pic, go to properties, highlight all the code, copy and paste it on your post
Title: Re: MOT failure - Handbrake
Post by: ad_car_08 on July 21, 2009, 10:42
Quote from: "Peter Wright"
Quote from: "ad_car_08"(Why aren't my pictures displaying?! I've wrapped the html in the "[img]" tags)
Bring flicker up, right click the pic, go to properties, highlight all the code, copy and paste it on your post
s8) 8) s8)  Nice one, cheers Peter
Title: Re: MOT failure - Handbrake
Post by: ad_car_08 on July 22, 2009, 15:00
Thanks all for your numerous replies....  s:lol: :lol: s:lol:  

Had a phonecall from the mechanic, apparently the handbrake cable was stretched and therefore wasn't able to apply the passenger rear brake firmly when the handbrake was tugged on.
Cable to be replaced today and car sent for an MOT this afternoon - wishful thinking on his behalf I think....I hear the handbrake cable is a right PITA to replace?
Title: Re: MOT failure - Handbrake
Post by: nathanMR2 on August 29, 2009, 09:03
Quote from: "ad_car_08"Thanks all for your numerous replies....  s:lol: :lol: s:lol:  

Had a phonecall from the mechanic, apparently the handbrake cable was stretched and therefore wasn't able to apply the passenger rear brake firmly when the handbrake was tugged on.
Cable to be replaced today and car sent for an MOT this afternoon - wishful thinking on his behalf I think....I hear the handbrake cable is a right PITA to replace?


How did you get on with the cable replacement mate? My handbrake seemed alittle loose so when it went in for a service the other day i asked them to have a look. They suggested that the caliper was sticking on the one side. This seemed to ring true as when i did my short shifter replacement the other day i noticed that the metal bar near the handbrake was not level (same as yours)

The most amount of DIY work ive done to this or any car is the short shifter, O2 sensor replacement and changing front brake disks and pads. With this in mind... If i get the calipers off and send them for a refurb im guessing the system will need to be reblead once done. Can i do this myself or does it need to be pressure blead? I had some issues many years ago when i did my motorbike capiler and nearly lost all my hair trying to blead the bugger!   s:lol: :lol: s:lol:
Title: Re: MOT failure - Handbrake
Post by: ChrisHumes on August 29, 2009, 09:14
can you keep this thread up to date mate - exactly the same problem i had yesterday!
Title: Re: MOT failure - Handbrake
Post by: BlackSabel on August 29, 2009, 13:36
Yes please guys can you keep this thread up to date mate - I have exactly the same problem and hence no MOT at the moment!
Title: Re: MOT failure - Handbrake
Post by: ChrisHumes on August 29, 2009, 15:44
a bit odd this is the first ive read about the problem and now we all have the same issue!
Title: Re: MOT failure - Handbrake
Post by: normanh on August 29, 2009, 19:19
Before looking to a sticky caliper look to see that one cable hasnt siezed, by checking the mechanism on the back of the caliper is free and the lever works with the hand brake off.


normanh
Title: Re: MOT failure - Handbrake
Post by: ad_car_08 on September 4, 2009, 15:52
Sorry for the delay in reply folks!

I took my car back to the mechanic, who whipped my wheel off and apparently banged, thrashed and greased my caliper back into life!
Can't say I'm managing to pull handbrake turns or that my handbrake is as efficient as an "E-brake" off'uv Fast & Furious, but it passed the MOT non-the-less!!

£30 later and a free retest, I've got another 12 months ticket!   s:D :D s:D
Title: Re: MOT failure - Handbrake
Post by: Anonymous on September 20, 2009, 20:44
Well add me to the list too! MOT yesterday, got a pass but was advised that the handbrake was right at the minimum level (33% efficiency). So looking to adjust it in the very near future. Have just read through the how-to and judging from where the adjuster is it's possible I knocked it earlier in the year when I stripped the interior due to internal flooding as the handbrake used to be fantastic.   s:oops: :oops: s:oops:  

So fingers crossed to an easy fix!
Title: Re: MOT failure - Handbrake
Post by: Bossworld on January 22, 2017, 17:56
I'm sorry to bump an old thread but spent all yesterday on mine.

Handbrake cables have just been replaced but after that I had no handbrake.

Yesterday I took it all apart, cleaned and greased all sliders, pad clips etc. Checked that both lever arms moved under hand pressure and made the piston move out (cables disconnected).

Did the full rewind and unwind by 180. On axle stands all seemed fine.

Took the car out today, still wasn't really holding. Slammed on the anchors a few times, low and behold all now seems well and holds well on an incline.

But:

1) Came home and after jacking up the car again, when the handbrake is applied five clicks, I can move the rear driver's side wheel (with considerable force). But, the passenger side requires even more force, which suggests the handbrake isn't applying evenly.

2) The equaliser bracket in the pictures above (and hence replying to this thread) isn't level. To my knowledge one cable is longer than the other, and I think you'd struggle to get the cables reattached if this wasn't the case. On the passenger side, a small piece of plastic casing on the wire is visible in addition to the metal cable. No such plastic casing on the driver's side. When you watch the cable as you pull up the handbrake, you can see the driver's side cable moves more, presumably because there is less tension on the passenger cable due to the equaliser slant.

Before I go mad, is this slant normal (all pics suggest so)?

I reckon I've got more than enough to pass an MoT, my only other thought was to tighten the adjuster (I've only got about 1cm of it visible above the locknut at present) but I'm starting to think I should just leave it while it all seems to be working.
Title: Re: MOT failure - Handbrake
Post by: gazza1286 on January 22, 2017, 19:10
Quote from: "Bossworld"Did the full rewind and unwind by 180.

This isn't 'necessarily' the correct procedure. The piston must be rotated such that the pin/stud on the inboard pad plate will locate into the recess on the face of the piston when the caliper swings into place.
Title: Re: MOT failure - Handbrake
Post by: Bossworld on January 22, 2017, 20:21
Quote from: "gazza1286"
Quote from: "Bossworld"Did the full rewind and unwind by 180.

This isn't 'necessarily' the correct procedure. The piston must be rotated such that the pin/stud on the inboard pad plate will locate into the recess on the face of the piston when the caliper swings into place.

It's been argued to death on other forums mate, could well be a placebo thing but I didn't fit new pads while doing this, so had plenty of space to do it anyway while ensuring the little pin lined up too.

 l viewtopic.php?f=11&t=30655&p=374733 (http://www.mr2roc.org/phpBB3/viewtopic.php?f=11&t=30655&p=374733) l

Any thoughts on the other points?
Title: Re: MOT failure - Handbrake
Post by: gazza1286 on January 22, 2017, 20:45
The slant on the equaliser plate is normal.
I've never heard of that 180 degree 'trick' but I can understand the logic/theory. The advancement mechanism within the rear caliper is crude and will only work as designed when all of the sliders are guaranteed to work correctly. I must be lucky as I've never had any handbrake problems in the 10 years of ownership.
The artificial advancement of the piston by 180 degrees will make that caliper a little tighter and could cause some binding. On the side which is weaker you could perhaps unwind the piston half a turn. That will undoubtedly change the piston stroke when the handbrake is activated. It won't last though as once the 'excess' brake material is worn back you'll probably be back to square one.
Did you fully extract the lower slider collar before lubrication?
Title: Re: MOT failure - Handbrake
Post by: Bossworld on January 22, 2017, 21:03
Quote from: "gazza1286"The slant on the equaliser plate is normal.
I've never heard of that 180 degree 'trick' but I can understand the logic/theory. The advancement mechanism within the rear caliper is crude and will only work as designed when all of the sliders are guaranteed to work correctly. I must be lucky as I've never had any handbrake problems in the 10 years of ownership.
The artificial advancement of the piston by 180 degrees will make that caliper a little tighter and could cause some binding. On the side which is weaker you could perhaps unwind the piston half a turn. That will undoubtedly change the piston stroke when the handbrake is activated. It won't last though as once the 'excess' brake material is worn back you'll probably be back to square one.
Did you fully extract the lower slider collar before lubrication?

Thank you.  Yeah I've spent hours pouring over various threads and have about 10 sheets of A4 printed in the garage with different instructions/routines   s:lol: :lol: s:lol:  

Fully removed the metal slide bit from the lower and used mintext ceratec on all parts so it won't affect the rubbers.  

Believe all parts of the brakes are now working (the problematic side had no handbrake at all when I first got the car as the cable was well and truly solid, and on last weekend's trip to Carlisle, the disc had a ring of rust round the outer where it clearly hadn't been engaging properly under normal braking either).   I'm still tempted to get a couple of new lower slider pins as mine aren't in great condition (although the caliper 'floats' cleanly now they've been cleaned and lubed up).  

Still, several emergency slams to test earlier this afternoon and there's no pull to either side, and the handbrake seems to be working in real-life situations.  Bit loathe to tinker again but will certainly consider winding that side out.

I'm probably reading far too much into it for a 12 year old car and I would certainly hope it would now pass an MOT even if there's a small imbalance?  I guess it probably needs a couple of hundred miles of driving too just to let everything settle down but you've got me tempted by some new slider pins.
Title: Re: MOT failure - Handbrake
Post by: Jon_G on January 22, 2017, 22:25
The equaliser plate on the handbrake is designed to slant and so accommodate any inequality in the cables and/or calipers mechanism. I guess it could be straight, but mine isn't.

You don't have to wind out the calipers piston the whole 180 degrees, but just enough to ensure that the thread has engaged and is beginning to 'unwind'. I used about 90 degrees when I recently replaced the rear discs, pads and a calipers... 180 degrees meant that I couldn't get the caliper back on and into position.
Title: Re: MOT failure - Handbrake
Post by: Bossworld on January 23, 2017, 13:20
Thank you.  I've ordered a couple of slider pins, only 1.19 each (exc. VAT) from Toyota so at least that's the rears that I can leave alone for another year after this.