Can't get a 12mm bolt off a brake caliper?

steve-L

WD 40 is better than nothing..... WD40 left over night is way better than nothing.... butane torch (or gas soldering ion with torch/creme brulee torch is what I actually have/use... unwanted present long ago...)

Breaker bar is really the trick....
1) Buy a good quality socket head.... preferably half inch
2) Get a breaker bar not ratchet
3) Make sure the car is on blocks!!!!!

If that doesn't shift it with penetrating oil/heat its a trip to the garage or somewhere with oxy-acet.... HOWEVER a good 3' breakr bar and good quality well fitting socket (worse case araldited on to the nut) should move more or less anything!

Course if you resort to Araldite you will have to bin the socket and nut and get a new nut after!

I got a breaker bar with 1/2 inch, if your anywhere near Woking you're welcome to borrow!

reeac

rix195 wrote: »

I have a vauxhall corsa c reg 53 so i'm trying to change my worn out front brake pads. I have taken the left front tyre off. I have jacked the car up on a floor hydraulic jack. Now i'm using a 12mm socket with a ratchet to take off the two 12mm bolts so that I can get the caliper off and change the pads. I can't get the top one off or the bottom one off either. Are they seized? Both bolts have rust on them and I have used my strength and i'm sweating and i'm a man but still can't get them to turn. Am I turning in the right direction? As this is my first time changing brake pads. I am pushing down in the left side with a ratchet on the bolt. I have used wd40 but with no success. Any help?

I've always found an impact screwdriver with 1/2 inch socket drive to be the most effective tool. Just make sure that it's set to loosen rather than tighten!

forgotmyname

If your struggling with a bolt i do have to wonder if you know what your doing.

Checked the braked fluid level?

Wig

Surprised no-one has mentioned this. EDIT..I see Gilbert &S did mention it post#6

You will need a 1/2" 12mm Impact socket




You will notice it has 6 sides for your 6 sided hex head bolt. Tap it on with a hammer, then use a 1/2" bar




Then the important bit is to turn the bolt anticlockwise when looking at the bolt from the top end.

You may need to use either a longer bar or just fit an extension pipe, however, the longer it is ...it will become obstructed by the ground and by the bumper, or by the wishbone. You will have work around this by rotating the socket by one "side" or 60° and then re-fitting the bar to the drive till you get the correct bar position.

For the left hand (passenger) side of the car, you will want the bar on on the socket, with the bar handle extending down to touch the gound underneath the bumper. Then stand infront of the car grasp the bar and lift it upwards against the underside bumper.

For the right hand (Driver) side wheel you want the bar to extend so it is touching the underside of the bumper 6 inches off the ground standing in front of the car press down on the bar with your foot, press it down to the ground.

If you are turning it the right way with your inappropriate tool (ratchet) not only are you probably going to break your ratchet, but it probably has locking compound on the thread. When I do mine I certainly don't use thread lock, but the first time I did them they had thread lock on them.

I also have to say if you are struggling with this, you really should not be doing something like this without help from a friend who knows what they are doing. Because after this, you have to put it all back together to the right torques.

TrickyWicky

gilbert_and_sullivan wrote: »

For goodness sake, WD40 is not a penetrating oil it will not penetrate rust, you might as well spray Coca Cola on it, at least that will work given enough time.

Get some Plus Gas or other penetrating oil.

Perhaps you would care to tell us all where we can find this then? I've tried time and time again at Halfords and my local independant parts dealers but I can't get it anywhere.

gilbert_and_sullivan wrote: »

Then get a set of impact sockets for jobs like these, 6 sided sockets not 12 sided as found in most inferior quality sets, will grip the bolt or nut head properly.

I have a very good draper 12 sided socket set. It was an excellent investment, cheaper than the halfords equivalent, has all but one of the missing sizes in other sets and despite a lot of abuse over the last three years, is still going strong.

Call that inferior?

Then I have two Halfords vortex sets from their 'professional' range. One of those sockets had to go back as the hole inside was off centre. The irony being that set cost more than the draper 'inferior' 12 side set.

gilbert_and_sullivan

TrickyWicky wrote: »

Perhaps you would care to tell us all where we can find this then? I've tried time and time again at Halfords and my local independant parts dealers but I can't get it anywhere.



I have a very good draper 12 sided socket set. It was an excellent investment, cheaper than the halfords equivalent, has all but one of the missing sizes in other sets and despite a lot of abuse over the last three years, is still going strong.

Call that inferior?

Then I have two Halfords vortex sets from their 'professional' range. One of those sockets had to go back as the hole inside was off centre. The irony being that set cost more than the draper 'inferior' 12 side set.

Ebay for Plus Gas if there are no motor factors worth bothering with round your way.

Firstly i don't buy tools needed for high forces at Halfords, secondly a 12 sided socket will easily round off a tight nut/bolt and will stretch over time unless very well made, thats why 6 sided are used for Impact and Professional quality sockets.

Tip...avoid Chinese made tools when they absolutely must not fail.

Robisere

Buy a Haynes Manual for your model.

This will tell you not only how to do it, but what tools to use and how best to go about it.

I really think that you may end up paying out more in the long run, by trying to avoid using a professional. Supplying and fitting brake pads on such a small car, should not be mega-expensive. Break the nuts, or a caliper, and you will be paying for a Recovery service as well as much more for more parts, and a brake bleed.

But it's your decision.

Wig

There would, however, be no point using WD40 or Plus Gas because the bolt threads are deep inside the caliper and nowhere near the bolt head which the OP can see.

Wig

TrickyWicky wrote: »

I have a very good draper 12 sided socket set. It was an excellent investment, cheaper than the halfords equivalent, has all but one of the missing sizes in other sets and despite a lot of abuse over the last three years, is still going strong.

Call that inferior

6 sided is always better when using high torque.

skivenov

Heat should be avoided on brake calipers because if you get it wrong you can melt the seals and boil the brake fluid. Yeah, we've all done it when it's come to desparate times, desparate measures, but it's not a good idea.

Applying a steady force to seized fixings doesn't free them, it's better to "shock" them with a sudden application of force. Either by quickly pushing down on a bar, or using an impact driver (the ones that look like a screwdriver that you whack with a hammer).