Rear drivers side brake/caliper sticking

[vatovey]

Evening all,

Went for a 20 minute drive to halfrauds on Saturday, when I got home I noticed a burning smell, upon checking I noticed it was coming from the drivers rear wheel area, with the wheel being quite hot aswell.

I am assuming the brakes/capliers have stuck on, is it a case of buying a refurb kit and refurbing the caliper/piston and associated springs and rubbers ?

I just checked - do Brakes International still do a refurb kit for MR2's ?

Thanks, Vaughn.

[frogger]

Yeap, just need to get
(a) a kit from brakes international (they still do them, click the 'associated' button next to the relevant caliper on their online ordering system)
(b) some red rubber grease (off ebay or from a local motor factors) Do not use any other grease on areas in contact with rubber seals on brake calipers.
(c) If the piston has seized up a bit, then buying a new one is prudent.

Before you order anything pull the caliper off and have a look to see if the piston is hard to move, or if its the sliders (or if its both).
All of these are common. Also give the other side an inspection and test too, as its usual for the other side to be approaching a similar condition!

That is assuming you're happy to do the job yourself, otherwise you can get a recon'd budweg caliper from brakes international (expect it to cost £80ish extra for that though!).

If rebuilding the caliper yourself...

...if you need any guidance when it comes to replacing just shout, have refurbed many of them.

Slider boots are very straightforward, cant go wrong there.
Piston dust boot is a bit of a pain (to get the circlip in place) - just take your time, dont use sharp tools, and be very careful not to tear the rubber!
If the piston is stubborn then this is where the fun comes in. If this is the case then let me know, I won't bother to go into detail otherwise!
Then there's jsut the trick to adjusting the rears correctly which is NOT included in the how to on this site (still) - but is documented in my previous posts.

[vatovey]

excellent - cheers Frogger.

Can I get the Brakes International kit from local motor factors, or is it a case of buying from BI themselves only ?

[frogger]

Motor factors are unlikely to be able to help, unipart in particular has the wrong parts on their system for 1999 onwards MR2 rear calipers, useless!
At best I would expect they may be able to source you a recon caliper for a bit more than one from brakes international.

To the best of my knowledge you have to order direct from BI.
Brakes international are certainly the only place to go to for pistons, and usually a good supplier for the kits.
They're usually quick to deliver, though some parts may come from germany which takes at least 48hrs as a guide time.

Bigred on ebay has an alternative option for pretty much the same price (considering this kit is for 2 calipers):  m http://cgi.ebay.co.uk/Toyota-MR2-1-8-Br ... 0127588342 m     I have bought several kits for other cars from this seller in the past with no issues.
Also pretty quick to deliver, probably not much to choose between this kit and the brakes international seals.

Toyota dealership will sell you an equivalent seal kit for more ££, probably for next working day collection.
I priced up everything from toyota in the past, and it's not really worth considering given the cost premium on some parts.
Strange as they're very competetive in price for Mk1 MR2 caliper rebuild kits which are basically the same!

[vatovey]

again - excellent  s:) s:)

I've just bought a set of of the bigg red repair kit.

I will buy some red rubber grease tomorrow in preparation.

To perform the refurb I have printed this off :  m http://www.mr2oc.co.uk/know-your-2/mk1/ ... ipers.html m

I know it's not for a MR2 Roadster, but from the reading I have done it sounds like the brakes/calipers in the above article are very similar/identical to the Roadsters, could you confirm Frogger ?

[AC]

Check your Handbrake cable that runs to that side in case it's sticking and causing the caliper to remain clamped.

I now suspect that to have caused my rear n/s to drag as I free'd it off a second time and haven't since used the h/brake and I've had no problems - so 2 new cables going on at MoT end of this month.

[frogger]

As AC says, worth inspecting whats going on closely when you start taking everything apart to do the refurb.
Checking whats seized and whats not will give you the awnser.

That guide for the mk1 calipers is indeed appropriate - they're pretty much identical in design.

I've only skim-read the how-to, but although I noticed that its got a 50/50 good/bad rating, I couldn't see anything massively wrong on the surface.
I would add the following points...

- Would NOT recommed using wet and dry paper of any grade on your piston. Asking for trouble. If the pistons crud, replace it!

- The brake caliper rewind tool (sold in halfords and on ebay, made by laser) can make life so much easier than pliers - well worth it in my opinion.
Especially if the piston is stubborn, then its a life saver. If the piston is seized then extra tools again are required... thats another story...

- The method of using the brake pedal to pump the piston all the way out (before you take off the hydraulic line) can save a lot of faffing around, especially if you dont have an air line handy to do it later on.

- Chances are the new pistons they bought in that how-to guide were the correct ones, but you need to cut up your old pistons to obtain a part from within them before they will fit... again, this is for another time if your piston is siezed or in need of replacement!

- After scraping all the old muck out of grooves I like to flush through with brake fluid to make sure there isn't the slightest trace of anything knocking around inside the caliper that could damage a seal later on.

- 'Step 16' in that guide might take 1 minute or it might take 1 hour, just have patience!
If things are getting difficult at this step it can help a lot to thouroughly dry any brake fluid/grease off the stuff your working on (and your hands) and get a better grip again.

- As mentioned already, only use red rubber grease. Almost anything else either swells rubber seals over time (causing seizing) or doesnt sufficiently protect against water ingress (causing rust and... siezing).

Good luck!

[BOGEYMAN]

this a fault with most rear toyota calipers of a certain age the piston cannot be screwed in, so unfortunatively its a new caliper.

[frogger]

Don't know where you've got that from!?

Every 'new' caliper on the market is just an old one thats been refurbed with new seals and new pistons (and sometimes replacement handbrake mechanism components)... buying a 'new' one (i.e. a recon from brakes international/toyota/motor factors) is not any different to doing it yourself.
Other than you have to put the effort in instead of someone else of course, and trust your own workmanship rather than someone elses.

You are 100% correct when you say this is a fault with most rear toyota rear calipers - rubber has a finite lifespan and when it goes corrosion grows.
BUT - I have yet to meet one that cannot be refurbished. Including many 20~25 year old ones that have been seized for a fair while previously.

The one thing that always stays great are the internals, its all just seals and occasionally piston corrosion and/or surface corrosion around the piston dust boot 'lip'.

[Dyn-Evo]

Just out of interest, the Toyota seal kit is not too pricey, considering you get sachets of both greases included......  s:wink: :wink: s:wink:  

(D/brake cyl. kit)  04479-17050   @ around £60

also, you may need a shim kit:  04946-17010  @ around £13

[kentsmudger]

again - excellent  s:) s:)

I've just bought a set of of the bigg red repair kit.

I will buy some red rubber grease tomorrow in preparation.

I realise this is a bit late, but another option is Bigg Red do a refurb service themselves - Anyone else looking at this issue can read more details HERE

[vatovey]

Ordered some of the red rubber grease from local motor factors, should be in stock tomorrow.

Whats the best way of cleaning off all the gunk n corroson on the caliper and piston/slider ?

[frogger]

If its a polished metal part (like a slider pin or piston) stick to solvents and scrubbing (brake fluid can work well).
Scrub with something softer than steel and you can do no damage.

For very stubborn muck on polished parts I use some of the fabric material type brushes on a dremel at a few thousand rpm.

If its muck on the body of the caliper (i.e. the rough cast iron parts) I go all over it with angle grinder with wire brush attachments, then scrub any particles off with solvents/petrol/brakefluid etc so that you're working with a clean caliper and there is nothing left to go inside the caliper when you take the piston out.

[vatovey]

Am halfway through refurbing the drivers side rear caliper, I've tried cleaning the piston but there is corrosion and slight pitting, as such I've just ordered 2 new pistons from Brakes International.

Am having trouble putting the spring clip back in after the new piston rubber..., is there some special technique to refitting the spring clip ? what a pig of a job lol   s:oops: :oops: s:oops:

Frogger - to save me looking, any chance you could copy and paste your guide to altering the handbrake - now I have everything apart I would like to get it working perfectly also.

[frogger]

No problem - Here's Les's guide on replacing rear pads:  l viewtopic.php?f=47&t=17198 l

And here's the one thing thats not included - Essentially once you've wound the piston all the way back in, wind it back out again by about 180-ish degree's   s8) s8)

Here's some discussion on the matter:  l viewtopic.php?f=11&t=30655 l
It's true that you can get suitable handbrake performance without this step - but doing this step is the only way to ensure a good handbrake first time everytime.

(As an aside, get new rear discs and pads if you're rear calipers been stuck on for long enough to wear things out a bit, I'd be tempted too anyway just to start a fresh!)

Am having trouble putting the spring clip back in after the new piston rubber..., is there some special technique to refitting the spring clip ? what a pig of a job lol

Ah yes lol. This sounds like the part I was referring to when I said "might take 1 minute or it might take 1 hour, just have patience! If things are getting difficult at this step it can help a lot to thouroughly dry any brake fluid/grease off the stuff your working on (and your hands) and get a better grip again."   s:lol: :lol: s:lol:  

I have no quick tricks unfortunately, just lots of swearing and persistance whilst trying hard not to damage the rubber!
I use some very thin spatula bits of metal to guide it in, rounded edges to not slice thru the rubber. You could file the edges of a couple of small screwdrivers.
I intend to get some circlip pliers to see if they help things, but im not sure there's enough access to use them anyway...
IIRC how far you wind the piston in can help, put the boot properly into position over the pison, and just try and line it up so you can get as much all round access as possible, with the boot all bunched up but flat (I think! I spend so long fecking around from different angles at this stage I forget!).

If you've bought new pistons my main advice with the circlip would be dont bother refitting that circlip until you've sorted the new piston's - cause you'll just have to do it again!  s:lol: :lol: s:lol:  

Regarding the new pistons... do you have an angle grinder, a dremel, or ideally both?
It's not a pretty job getting the internals out from your exiting pistons without damaging them! And the internals needs to be reused in the new pistons   s:( s:(  

To clarify, on the left here is your current piston. On the right is a brakes international piston (with internals reused):


And here's how you get to the internal gubbins...


Fun job eh?!?!

Notice that in these pictures the piston has been cut at exactly the right point - exactly on the line where the plate sits - yet the plate is not damaged in the slightest. This is not easy, but achievable if you're careful! For accuracy I cut out the bulk with a grinder, then trim out the little flats holding the internal plate in with a dremel.

Whilst I have done this procedure a few times, the above pictures are not my own, and form part of a full write up on mr2turbo.info ( m http://www.mr2turbo.info/pics/rearcaliper.html m )

[vatovey]

WTF !!!, it doesn't say on the webpage that I would have to re-use parts, I assumed it would be a completely new piston with all internal parts pre-built.

Not your fault Frogger - but if they come as you described, I will be sending them back, its false advertising surely ?, I don't have an angle grinder or a dremel  s:( s:(

Thanks for the info once again, been a lifesaver !!

[frogger]

lol, well technically the piston is just the outside bit!

Sorry, I did try to mention about it! ...

If the piston is stubborn then this is where the fun comes in. If this is the case then let me know, I won't bother to go into detail otherwise!

If the piston is seized then extra tools again are required... thats another story...

Chances are the new pistons they bought in that how-to guide were the correct ones, but you need to cut up your old pistons to obtain a part from within them before they will fit... again, this is for another time if your piston is siezed or in need of replacement!

If they have arrived by Monday I'm not too far away from you as it goes and will be (probably) be passing thru on monday if grinder services are desired   s:lol: :lol: s:lol:  
I can bring the kit easy job, all that would be required at your end is a decent vice or something to hold the piston steady?

How bad are your old pistons, any pics?

[vatovey]

they arrived this afternoon and are exactly as you described.

I spoke to Brakes International and they said I could simply remove the internal parts from the old piston with a circlip pliers - obviously they are not aware of the design by Toyota  s:( s:(

On the positive side, they did say that if I can't get the internals out myself that they would fully refund me - which was nice.

I shall take some pics and get them uploaded in a few minutes, I've only disassembled the drivers side rear atm, the passenger side piston would be in similar condition I'm assuming.

[vatovey]

ok, here is the piston which has been removed from the car.



Unfortunately there is nobody around on Monday, I'm in work until 5pm and then go straight to night school until 9pm  s:( s:(

Looking at the condition of piston in the picture, can I simply grease up the corroded part of the piston with the red brake grease I bought, or is it worth wet and dry sanding the corroded part of the piston - I have some extremely fine wet and dry paper which I used to remove oxidation from the mr2 headlights.

[frogger]

Hmm, I've seen worse...

Is that actually corrosion on the main body of the piston? ...
Or is it firmly baked on muck that might come off with a plastic based scouring pad and some solvent abuse?!

If it's possibly muck, then as mentioned previously, I'm not a fan of wet and dry paper (or any abrasive materials harder than the steel of the piston) as, by definition, these materials are capable of wearing down the metal of the piston - Whereas alternatives such as plastic/nylon scouring pad will only remove gunk, and leave the metal of the piston unscathed...

If it is actually corrosion, then of course piston replacement is the correct method... though there is a chance you could be successful with wet and dry paper... but I don't recommend it personally   s:wink: :wink: s:wink:

[vatovey]

It's corrosion  s:( s:(  , I've tried cleaning it but not much actually came off, used a toothbrush and some new brake fluid.

I really would prefer to replace the caliper, but getting the internals out of my old pistons is going to be a major issue I think.

[frogger]

Aye, sounds like it could do with replacement.

PM Sent!

[vatovey]

Went up to Gloucester on Saturday for Frogger to angle grind my old caliper pistons - all done within' an hour, THANK YOU VERY MUCH !!

Here's a quick shot of Frogger in action.



I have since re-assembled everything and it's mostly good, I think I need to bleed the brakes once more as they feel a little squishy.

Aswell as the brake bleeding, during re-assembly I noticed one of the tinware pieces which align the actual brake pad in the stationary caliper is missing, due to this the brake wear is uneven and probably the cause of all my brake problems I suspect,  can anyone advise as to where can I get hold of replacement caliper tinware ?

Thanks, Vaughn.

[frogger]

No problem, always happy to lend a grinder!

Regarding the missing bit, are you talking about a missing clip, or a big flat piece?

If its a clip, then they're pretty vital, but I haven't got a clue where to suggest... cheaptoyotaparts or Toyota I guess.

The flat bits are just antisqueal shims, I leave them out all round and use a slithering of copper grease on the back of the pads instead.
These (or the lack of these) won't affect the wear, though you'll always tend to get slightly uneven wear with this design of caliper anyway IIRC.
Certainly a siezed slider or sticky piston will create a lot of uneven wear though!

On a semi-related note: Did you get new copper washers in your rebuild kit from bigred? Or did you reuse the existing ones? Seemed to be the only thing missing from kit's I've had in the past.

[vatovey]

It's a missing clip which fits on the stationary part of the caliper (i think the stationary part is bolted to the wheel hub).

Does anyone have a Toyota or CTP part number for the above tin clips ?

Washers - nope, wasn't included in the kit.

Update: Just spoke to my local Toyota dealer - I tried explaining what the part I want is, hopefully they have ordered the correct part - waste of £3 otherwise  s:( s:(