Binding brake, grr
Discussion
Morning all,
Took the MX5 to work today as it's a lovely day but I noticed that the front nearside brake is binding again! This time it seems a bit worse as you can feel it when the car is moving at very slow speeds (like <5mph) and the wheel is getting rather hot.
It happened before but I gave it all a clean and it seemed OK for a while. But I think it might be time for new calipers!
If it is just a siezed sliding pin, what sort of grease do I need?
If it's the caliper, do I need to replace both front ones?
If so, do I need to bleed them or will clamping the flexible part of the brake hose be sufficient?
If I do need to bleed them... How do I do it?
Will just doing the fronts be sufficient?
Is it going to damage my pads?
Thanks chaps!
Took the MX5 to work today as it's a lovely day but I noticed that the front nearside brake is binding again! This time it seems a bit worse as you can feel it when the car is moving at very slow speeds (like <5mph) and the wheel is getting rather hot.
It happened before but I gave it all a clean and it seemed OK for a while. But I think it might be time for new calipers!
If it is just a siezed sliding pin, what sort of grease do I need?
If it's the caliper, do I need to replace both front ones?
If so, do I need to bleed them or will clamping the flexible part of the brake hose be sufficient?
If I do need to bleed them... How do I do it?
Will just doing the fronts be sufficient? Is it going to damage my pads?
Thanks chaps!
Edited by Howard- on Friday 21st May 08:23
They bind in one of two ways -
A - the slider pin gets stuck
B - the piston corrodes and gets stuck
A is an easy fix.
Undo the bolt on the bottom rear of the caliper as if you were changing the pads - swing it up, and itll pop off. Blast off the slider pins with brake cleaner. Blast inside the rubber tubes too. Clean out with a rag/q-tip. Regrease the sliding assembly using high temp grease (buy a tin of it, will last you forever) and refit.
B - you can do a 'quick' emergency fix if you have a piston windback tool and a mate - do as before and remove the pads. Get mate to SLOWLY press the brake - you'll see the piston push out. DO NOT LET IT POP ALL THE WAY OUT.
You'll be able to peel back the rubber seal and inspect - I guess it will be well grotty. Use a bit of brakefluid as lubrication around the piston (Inside the seal). Use the windback tool to wind the piston back in. repeat process a few times, working the piston back and forth in the caliper, this may free it off for a short while.
To fix it properly - you need to sort the caliper.
Most people seem to opt for buying new/reconditioned calipers.
They say that its 'not worth the effort' to rebuild your own, is difficult, etc. Madness.
Calipers are gonna cost you about £160 IIRC for a pair.
You can strip, paint, and rebuild them both for about £50 - seal kit, pistonsnew crush washers, a litre of brake fluid and a tin of hammerite.
Et voila - nice clean shiny working calipers, AND £100 in your sky rocket. I dont knwo about you, but I value that - my time is cheap!
Yes you'll have to bleed the brakes - but again this is easy (do it with a friend the proper way, not fannyign about with an ez-bled) and you may aswell do all 4, especially if you dont know how old your fluid is.
A - the slider pin gets stuck
B - the piston corrodes and gets stuck
A is an easy fix.
Undo the bolt on the bottom rear of the caliper as if you were changing the pads - swing it up, and itll pop off. Blast off the slider pins with brake cleaner. Blast inside the rubber tubes too. Clean out with a rag/q-tip. Regrease the sliding assembly using high temp grease (buy a tin of it, will last you forever) and refit.
B - you can do a 'quick' emergency fix if you have a piston windback tool and a mate - do as before and remove the pads. Get mate to SLOWLY press the brake - you'll see the piston push out. DO NOT LET IT POP ALL THE WAY OUT.
You'll be able to peel back the rubber seal and inspect - I guess it will be well grotty. Use a bit of brakefluid as lubrication around the piston (Inside the seal). Use the windback tool to wind the piston back in. repeat process a few times, working the piston back and forth in the caliper, this may free it off for a short while.
To fix it properly - you need to sort the caliper.
Most people seem to opt for buying new/reconditioned calipers.
They say that its 'not worth the effort' to rebuild your own, is difficult, etc. Madness.
Calipers are gonna cost you about £160 IIRC for a pair.
You can strip, paint, and rebuild them both for about £50 - seal kit, pistonsnew crush washers, a litre of brake fluid and a tin of hammerite.
Et voila - nice clean shiny working calipers, AND £100 in your sky rocket. I dont knwo about you, but I value that - my time is cheap!
Yes you'll have to bleed the brakes - but again this is easy (do it with a friend the proper way, not fannyign about with an ez-bled) and you may aswell do all 4, especially if you dont know how old your fluid is.
Edited by snotrag on Friday 21st May 14:13
Definitely gonna try the first "clean up" method first! If I do need to replace the caliper then it's not the end of the world, they're £60 from Autolink. I can't really be arsed to strip them down in light of this tbh! 
don't have time to sort one in the next few weeks so I'll clean it all up, better than I did last time (which cured it for a while) and get hold of a caliper in due course
ked. Oh well, time for a new one when I get back from holiday. I've had my car jacked up this afternoon and noticed the front n/s wheel stops very quickly if I use my hands to spin it and let go, whereas the o/s one continues to rotate freely. The same corner of the car has also been making a creaking noise when you brake at low speeds, which I had thought was a noisy bush. When I drive the car, it doesn't pull to the left and the wheel doesn't seem to get hot.
Any ideas? Have a got a ronnied caliper like the OP?
It's a Mk2.5 Sport btw, so big brake kit if that makes any difference (apart from costing more the replace!).
Any ideas? Have a got a ronnied caliper like the OP?
It's a Mk2.5 Sport btw, so big brake kit if that makes any difference (apart from costing more the replace!).
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