Brake Caliper re-e-e-e-wind tool

[Stanky]

Brethren,

 

I am required to change the rear pads on the Saab, as the old ones are somewhat low on friction material. I have duly purchased a set of mid-range Pagid pads to match the ones I did last month on the front, but the internet tells me its slightly less simple to do rears than fronts as the piston needs 'winding back', rather than just pushing stright back into its barrel.

 

Can someone explain how the process works? You need to rotate the piston as you push it in - is that right? and there is some kind of thing that you push or prod or wiggle while applying pressure to the piston so it sort of rotates back into the barrel rather than sliding straight back in like the front one does?

 

Do you need a solid diamond tool, manufactured to order by Faberge in a cave at the top of a mountain on one day a decade to do it or can you improvise with more commonly available tools? Or will this result in utter misery and broken calipers?

 

Thanks muchly, if it helps* I think the setup is the same as a Vectra C, in case anyone has done the same with one of them?

[Bren]

I bought a kit for less than £20 with two winding tools to do calipers that are handed eg mondeo.

 

You can "wind" the piston in with a pair of thin nosed pliers but dont slip with them.

[Stanky]

What happens if you slip? you stab yourself or the whole shebang explodes?

[panhard65]

You do really need the special tool that will turn the piston at the same time as pushing it back in. It can be done without a tool but is not easy as you have to turn it and push it back at the same time. If you are really unlucky some have left and right hand threads. I have an excellent air powered tool that will do either left or right hand thread that just needs a compressor to push the pistons back. You are welcome to borrow it but as I am in Somerset probably a bit of a trek

[Stanky]

I shall be assisting my wife's uncle who is a qualified mechanic in this job as I don't trust myself doing brakes unsupervised - I just want to know what to bring with me, or ensure he has before we commence the job and discover we don't have something important.

[Bren]

The proper kit makes the job a breeze - well worth £20, even if you only used it once it is cheaper than having pads fitted in a workshop.

[omegod]

You neeed three hands to do it without the tool and will likely damage the rubber piston seal, it's not worth the pain. £20 quid tool set is a godsend and will cover most cars

[dave j]

I have managed it with a g clamp and long nose pliers but its so much easier with the right tool! Luckily I borrowed one off a mate the last couple times I needed one.

[Christine]

Keep pressure on the piston , wind back with angle grinder key .( VW T4 )

[Eddie Honda]

Live on the edge save* ££££s

 

[cobblers]

Yeah, I've done it myself without the tool a few times on VW rears, with a nut/bolt and big wasger putting pressure onthe piston while I span it round with some waterpump pliers but its hard to do it without knackering the seal.

The rewind kits are £15 on ebay.

 

It needs winding back to readjust the handbrake mechanism inside it - there's a threaded rod with a threaded top hat that pushes on the inside of the piston when you pull the handbrake up. Twisting the piston winds the top hat back down the rod.

[Station]

I've done it loads of times with mole grips on the piston edge if it's a screw in one - you don't need to apply pressure if you take the reservoir cap off.

Or just push it in with a g clamp.

Kit is handy but fiddly as it's universal and doesn't fit all calipers.

[forddeliveryboy]

Yes, but if pistons are a bit sticky the kits make life a lot easier, and my £20 ebay one comes with a variety of attachments which work with almost all calipers.

[sierraman]

You also run the risk of slipping with the pliers and damaging the seals.

[Stanky]

[Vince70]

When I last had to rewind a caliper I used one of these things and it's meant to have the majority of the pin sizes on it to rewind your caliper back.

[Timewaster]

I found those cube things to be F useless.

Spend the fiver on a six pack and use it to bribe someone to lend you a decent tool.

[doobietoo]

I am pretty sure I have one I bought for doing the golf if its the same and I can find it you are welcome to borrow. I will be passing Southampton about lunchtime Saturday we could meet at the mway services or somewhere else close to the m27 / m3 if that is any help.....

[Stanky]

Thanks Doobie, that could be very useful - I'll ring my wife's uncle and see if he has managed to get hold of a wind back tool tomorrow - if not then yes please may I borrow it until the next auction meet up? Are you off up the M3 or coming out Fareham way? I can trundle over to Rownhams if thats easier?

 

I'll PM you tomorrow and let you know either way

[doobietoo]

you have a pm...

[Bren]

When I last had to rewind a caliper I used one of these things and it's meant to have the majority of the pin sizes on it to rewind your caliper back.

[attachment=50861:image.jpeg

If I remember it only cost about 4/5 quid on eBay but I still had to give it a tickle with the angle grinder to get it to fit on the pins of my old Audi.

About as much use as a one legged man in an arse kicking contest.

[Barry Cade]

Spray some WD40 (other slippyish stuff is avaliable) with the little straw that you lost the first time you used it, in the groove where the rubber dust cover sits on the piston, saves it sticking to the piston and twisting round as you screw it in.

[drum]

Before I knew about wind back pistons, I took the caliper off (an Astra I think) and battered the piston back with a hammer thinking it was sticky. Didn't seem to do it any harm!

 

I have since bought a £10 right handed one which is a bit of a faff but does work better than the hammer like feck method.

[beko1987]

My £17 set has been ace tbh! Firs everything ive tried bar the rear calipers on my zx, cos the pad carrier is in the way and the bolts were too stiff for me to bother removing! Has gone very rusty though despite only being rained on a few times, meh! A valuable addition to a toolkit imo, especially for a vauxhall

[Asimo]

Easy enough to make a wind-back tool with hacksaw and an old socket.

 

Choose a socket from that box of rusty old Whitworth sizes that you never use*.  About the same diameter as the piston you are winding back.

 

Saw off two bits of socket so as to leave a pair of pegs that fit the piston.

(Although socket spanners are tough, they are not hard and the steel saws easily)

 

Adjust with file if required.

 

Wind away.

 

 

*If you find Whitworth socket sizes useful, you probably don't have pistons to wind back into calipers.

[Andrew353w]

The proper kit makes the job a breeze - well worth £20, even if you only used it once it is cheaper than having pads fitted in a workshop.

 

Totally agree! I bought one of these kits years ago & it's paid me back muchly! The trick is to get the tool set up properly and doing the winding back g-e-n-t-l-y while keeping everything in place. Once you've either done it or seen it done you'll feel much happier doing it yourself next time. The kits are useful for pushing back non-handbraked sets of pads, too! 

[Taff]

X1/9 rear pistons have a slot on them which is 1/4 inch wide (it's probably the metric equivalent) so I used a 1/4" drive ratchet and extension bar to wind mine back in, along with just a soupcon of WD40 to protect my seals.

[twosmoke300]

Don't use wd40 on caliper seals / boots ! It will make them swell and distort the same as oil and grease does . Use silicone spray .

The problem with doing this is that you can't tell if the caliper has leaked while you wound it back . Swings and roundabouts I suppose as it does make it easier and less likely to twist the dust boot .