Sticky brake and handbrake problem

[Stephster]

When the little miss when in for her MOT, the mechanic mentioned her back brake was sticking ( which would explain the annoying squeak I get ) and that one side of the handbrake wasn't working.
My question is, is it worth having a look at myself ? Is it within the capabilities of a novice mechanic ? Also, what could be causing the above ?

[Anonymous]

 l viewtopic.php?f=47&t=33557 l

[Stephster]

Thanks, it appears it is a combined problem then !

[Stephster]

After reading it, I have just texted the mechanic to do the job !

[Steve Green]

If you need any clarification, PM me and I can fill in any missing details.
He will need circlip pliers to get to the inside of the caliper. Standard circlip pliers will not do the job.

[iPap]

I would put a bet on a knackered handbrake cable and they are a pain in the arse to change!

Same thing happened to mine, first I knew was a sticky caliper.

[Steve Green]

My experience says that if the handbrake isnt working properly, you check the calipers first.
Not worth going to the bother of dropping the fuel tank to change the handbrake cables, if the calipers themselves are seized. You will only waste time and money.
You can check the calipers easily by removing the rear wheels, disconnecting the handbrake cables from the caliers and then trying to operate the calipers  manually. Whilst there you can also check if the cables are seized. I have yet to be convinced that handbrake cables stretch, I believe thats an old wives tale and a total misunderstanding of how the handbrake system works.

Handbrake cables do seize and can fail, but you are in danger of replacing a light switch before checking whether the bulb has blown.

[frogger]

... and caliper siezures are much more common than genuine handbrake cable failures    s8) s8)  

So +1, always sort the caliper first.

[normanh]

I had a cable seize solid on a car less than 4 years old - MR2 Roadster at that - mine, cable replaced and perfect since.


norman

[frogger]

Still stand by my statement  s;) s;)

... if the caliper is siezed in any way, it should always be the first thing to sort.

[Steve Green]

I had a cable seize solid on a car less than 4 years old - MR2 Roadster at that - mine, cable replaced and perfect since.
norman

But I have just read some of your old posts to find that you too had a seized rear caliper and took advice from your brother.

Question, has anyone a detailed drawing/parts breakdown on the rear caliper? As I suspect I am having a few problems here as well. Better to see what I intend to clean up before I attempt the job. Had one disc corroded on the iniside which I cleaned up on fitting new pads but the had brake still does not feel right. Does anyone know if the handbrake mechanism in the caliper needs lubricating? I have had one new cable fitted as the old one was total siezed.

If people want to ignore my advice, or argue against it, please make sure your evidence is correct and consistant.

Too many people are going to the expense of changing handbrake cables when, in my and others opinions, it is totally unnecessary. Advice from many mechanics is doubtful unless they understand exactly how the MR2 rear brakes work, most will never have dismantled a caliper to find what is inside. Their motivation is to replace what they view as a faulty part, almost regardless of cost to the customer, and then send them on their way.
Even Mr T's mechanics cannot be trusted, their skill set is primarily in regular servicing, they must rarely see an MR2 these days if ever.
(Sorry if you are a Mr T mechanic, but I am sure you would fundementally agree)

My refurb guide is not for the faint hearted, often replacement of the calipers is the prefered option, especially if the car is a daily driver where other considerations than cost are important.

Yes, handbrake cables do fail. The last time I looked at mine I had water dripping from the inner sleeve, a sure sign that I will have some internal corrosion and I have a problem that will need to be addressed. But I obviously know my rear calipers are in good condition.

As I have previously said, I understand the temptation to change just one faulty caliper. My advice on all things brakes, suspension, tyres etc is to treat both sides of the car in a similar fashion. Safety is the key!

RANT OVER

[Anonymous]

I followed the guide and had a pair done in around an hour and that was taking it easy.  s:D s:D

[2 of the left]

I had the handbrake cable seize on the Mk2 - Is this a MrT design fault?  s:( s:(

[Steve Green]

I followed the guide and had a pair done in around an hour and that was taking it easy.  s:D s:D

Top man.  Problems set in when the pivot is really seized solid.

I had the handbrake cable seize on the Mk2 - Is this a MrT design fault?  s:( s:(

I first came accross the caliper problem on an MGF that uses a remarkably similar setup, common to Rover800 and very similar to later Honda/Rovers and some Fords
The Mk2 and Mk3 rear brakes are pretty much the same design.
The caliper design is not that unusual, I think it just gets ignored, a good splodge of water resistant grease over the actuator pivot should protect it between services. I dont think the handbrake cables are particularly suspect, but they do get a bad press IMHO due to misunderstanding how the brakes work. At least on a Mk2 you dont have to lower the fuel tank.

If there is a design fault on a Mk3 its more to do with corrosion on the steering UJ and power steering pipe fittings.
Not to mention oval bore etc    Others may be able to write a longer list.

[iPap]

The cables down stretch, they ingest water through damaged lines near the caliper.

But, yes don't just assume it the cable, pop the wheel off and check the caliper first and the cable whilst you are there!

[frogger]

The Mk2 and Mk3 rear brakes are pretty much the same design.

It's actually been the same basic caliper design since 1985   s:shock: :shock: s:shock:  Through Mk1's, Mk2's, and Mk3's

I don't quite feel able to say 'if it aint broke, why fix it' .... as I've rebuilt more sets than I can count over the years, so could be counted as a bit of a arse of a part!  

That said, it may be more a function of usage frequency compared to other vehicles.
There's no denying that MR2's on average see a below-par annual milage compared to many vehicles
(and some are also left sat during the coldest/wettest months)

Maybe this just isn't great for a component protected from the elements with just a thin slip of rubber.
When that rubber cracks/splits, enivitably moisture ingress follows - seals swell, metal components rust
...and then you're left with a very hot rear wheel assembly, and an afternoon in the shed covered in brake fluid!

[K T M Rider]

When the little miss when in for her MOT, the mechanic mentioned her back brake was sticking ( which would explain the annoying squeak I get ) and that one side of the handbrake wasn't working.
My question is, is it worth having a look at myself ? Is it within the capabilities of a novice mechanic ? Also, what could be causing the above ?

I take it that the side of the handbrake that isn't working, is also the side with the sticking caliper?

When I bought my current roadster (with about 10 days MOT left on it) it turned out that the passenger side caliper was sticking - which it failed the MOT on, no handbrake issues were mentioned though.

on my car it was just a seized sliding pin, which is alot easier to sort as you are not really stripping the caliper itself.

If you have handbrake issues (on the same side that the caliper is sticking   s:) s:)  ) then I suppose the seized auto adjusters are much more likely.  

If the sliding pin IS seized, your mechanic can hardly fail to spot it anyway.


picture of the caliper mounting bracket showing the sliding pin (shiny bit) before reassembly.

[Stephster]

Alan, it is the same side. Didn't fail MOT though, and didn't get advisory as the sticky brake is not bad enough and the other side of the handbrake is compensating for the failed side.
It's good to know that the strip down doesn't take that long, so will go down that route of looking at caliper first.
Thanks for all the advice and pics  s:) s:) .

[normanh]

On the advice point I did request some way back when I first had my 2 I got some for which I am grateful for, however the problem was not the caliper it was a seized cable that was replaced and I have not had a problem since!!! Caliper No, I can only say what I found in the end thats whats good about the forum. In closing I am not really sure what your problem is Steve because at the end of the day changing the cable by the Mr T who sold me the 2 cured I have never had to touch the calipers front or rear since other than pad replacements. In those early days I didnt know much but in over 6 years ownership I feel I am now able to pass comment.




norman

[Dyn-Evo]

Read all the above with interest....  s:D s:D  

Just feel I can add acouple of things:

1) The caliper can be sticking / partially seized without it being an MOT failure: the tester only checks that the brakes work on the rollers to a certain a spec (ie: they apply above a certain force to the disc when applied),
If they do this satisfactorily, both with the pedal and the handbrake, they have no reason to look further......

The caliper can still be sticking partially: its just that the fluid pressure will still be able to force the pad onto the disc enough to overcome the sticking.
This depends on how sticky they are: I would suggest that at least 40% of MR2 owners have this scenario, but only find out about it when it gets bad enough to fail the MOT.....?  s:? :? s:?  

2) Disconnect the handbrake cable from both rear calipers (easy job), then get someone to operate the handbrake lever, and watch what happens to the cable....?
Simples!

Another (often mentioned!) tip to help prevent handbrake problems is to leave the handbrake off/ car in gear, when the car is unused for any fair length of time (1 week+?)..

Finally, from experience, I reckon that the greases used can contribute massively to future problems..?
Toyota supply 2 types of grease with the rebuild kits...they do this for a reason...?

So when you refurb your calipers, if you go with general forum advice, and, say, use Coppaslip on BOTH applications, its POSSIBLE you could be starting a time-bomb ticking....

I'm not 100% sure about this, but its worth bearing in mind, especially if you consider the viscosity of the grease when it is freezing cold, and when it is 10 laps into a trackday stint....  s:wink: :wink: s:wink:  

Also, how they react when doused in brake fluid.....

Just a thought...  s:D s:D

[frogger]

Refreshingly sensible suggestions + observations the lot of them!

(1) Examine and identify the true problem  (a logical process that has been discussed at length in other threads)
(2) fix the problem properly   (a well documented process available on this forum in a couple of threads)
(3) maintain properly from then on   (several useful tips in post above and in the threads mentioned in points (1) + (2) )

[Stephster]

I have emailed the mechanic with link to this thread and the other one mentioned right at the beginning.

I have been leaving the handbrake off now that she is stationary for long periods of time, and putting bricks behind and in front of the wheels just in case - so I don't think it caused it.

I wouldn't have known  about stickiness unless tester had told me as for reasons mentioned above it didn't fail. Must have been going on for a while, 'coz I now think that has been the cause of a squeak coming from the rear.   s:oops: :oops: s:oops:  

When I discover what the problem is, I shall post again !

[Stephster]

DRUMROLL...........the problem is/was the handbrake cable - new one needed. Musn't grumble though as friend in the trade is getting me one for £35 and mechanic has quoted £50-£100 depending on how long it takes to fit.

[normanh]

Glad your sorted or nearly Stephster, not sure what the easier of the jobs is caliper rebuild or the cable but at least you know its the cable for sure now. Glad I was right with my diagnosis.


norman

[Steve Green]

DRUMROLL...........the problem is/was the handbrake cable - new one needed. Musn't grumble though as friend in the trade is getting me one for £35 and mechanic has quoted £50-£100 depending on how long it takes to fit.

Well I have been wrong before but pleased you are getting it sorted. Dropping the fuel tank is a pain.....

Would be interested in pics or info on the cable so that we can help others.