Seized and rounded caliper carrier bolts.

ukonline

Hi,

So I went to fit new rear discs and the caliper carrier bolts were seized. I ended up rounding the shizzle out of them.



I've tried Irwin bolt grips, vice grips, filed the bolt heads flat to get a smaller socket on them, cold chisel and hammer, heating with cheap blow torch, stilsen, cheap impact gun, nothing will even grip. Even cut a slot in one bolt head and tried with a large flat screwdriver to loosen it.

Hate taking it to a mechanic and paying through the nose.

What would happen if I cut the bolt heads off?

It's a 2004 Megane Estate.

These are the 2 bolts holding the caliper carrier to the wheel knuckle I think it's called, NOT the part that holds the pads. That came off easily.

Thanks in advance,

Are Am Eye

Did you try some pb blaster.

rex-x

Those bolts are extremely tight, you will need a seriously good fit to open them. There are special sockets available for the job.

On a side note on most cars you don't actually need to remove the carriers to change discs, they leave you enough room to get them out So many mechanics take them off anyway though out of habit......

ukonline

Are Am Eye wrote: »

Did you try some pb blaster.

Hi there, thanks for the tip. No, I haven't tried PB Blaster, but tried WD40 Fast Release Penetrant.

Main problem is nothing will grip the rounded heads. Everything I've tried just slips off.

Thinking about it now, I've been using a dremel type grinding wheel to try to get square edges, but cannot due to the grinding disc edge itself rounding. Maybe I should try the cutting disc for more accuracy?

ukonline

rex-x wrote: »

Those bolts are extremely tight, you will need a seriously good fit to open them. There are special sockets available for the job.

On a side not on most cars you don't actually need to remove the carriers to change discs, they leave you enough room to get them out So many mechanics take them off anyway though out of habit......

Yes, getting something to fit tight is the problem. Will try again with a dremel cutting disc to square the bolt head.

I have the Irwin special spiral fluted sockets.

I did undo the hub nut but the disc would not pass the carrier. But will have another look and see.

Thanks.

clement

Cut the heads off with a cutting disc. They are stretch bolts. Remove the threaded bit on the bench when you have the bracket off. You will need new bolts to reassemble. Wasting your time now no matter what you do without new bolts ready to go.

ukonline

clement wrote: »

Cut the heads off with a cutting disc. They are stretch bolts. Remove the threaded bit on the bench when you have the bracket off. You will need new bolts to reassemble. Wasting your time now no matter what you do without new bolts ready to go.

Okay. The bolts are M12, 1.25 pitch flanged. They cost 4 or 5 Euro each.

I'd already bought half a dozen M12 high tensile, 12.9, bolts, same pitch, for a tenner online, and separate high tensile washers. Would they do?

Thanks.

ukonline

ukonline wrote: »

Okay. The bolts are M12, 1.25 pitch flanged. They cost 4 or 5 Euro each.

I'd already bought half a dozen M12 high tensile, 12.9, bolts, same pitch, for a tenner online, and separate high tensile washers. Would they do?

Thanks.

Probably not!

https://www.reddit.com/r/Cartalk/comments/2d6ebh/replace_stretch_bolts_with_nonstretch_bolts/

dev100

ukonline wrote:

It's a 2004 Megane Estate.

Any pics ?

ukonline

dev100 wrote: »

Any pics ?

Sorry, no pics. Will take some tomorrow. Since I'm not sure if I can use the bolts I've got, I'll order the Renaults ones if I can find them. So looks like a few days more delay.

jimbis

If you ring Renault in the morning they'll have the bolts for you in the afternoon.

hamburg

Could you not weld an old nut on top of the ruined bolts and the whip them off? The heat from the welding will probably free up the ruined bolts as a bonus.

ukonline

hamburg wrote: »

Could you not weld an old nut on top of the ruined bolts and the whip them off? The heat from the welding will probably free up the ruined bolts as a bonus.

Good idea, but I don't know how to weld.

hamburg

If the car is driveable,then bring it to someone who can. Probably won't cost more than 10 -20 euro.

JohnBoy26

ukonline wrote: »

Hi,

So I went to fit new rear discs and the caliper carrier bolts were seized. I ended up rounding the shizzle out of them.



I've tried Irwin bolt grips, vice grips, filed the bolt heads flat to get a smaller socket on them, cold chisel and hammer, heating with cheap blow torch, stilsen, cheap impact gun, nothing will even grip. Even cut a slot in one bolt head and tried with a large flat screwdriver to loosen it.

Hate taking it to a mechanic and paying through the nose.

What would happen if I cut the bolt heads off?

It's a 2004 Megane Estate.

These are the 2 bolts holding the caliper carrier to the wheel knuckle I think it's called, NOT the part that holds the pads. That came off easily.

Thanks in advance,

Except you probably wouldn't pay through the nose for the work you want done from a good independent and you'd have the car back and working by now

CJhaughey

JohnBoy26 wrote: »

Except you probably wouldn't pay through the nose for the work you want done from a good independent and you'd have the car back and working by now

In the immortal words of Casey Stoner: "Obviously your ambition, outweighed your talent."

Autochange

i would hate to be the guy who has to fix your mess up. I would charge through the nose for it. best of luck

shietpilot

Did you use a 12 point socket or a 6 point socket? If you used a 12 point, chances are a 6 point will work and it's what you should have used in the first place...

Autochange

shietpilot wrote: »

Did you use a 12 point socket or a 6 point socket? If you used a 12 point, chances are a 6 point will work and it's what you should have used in the first place...

Good point. another is to put some valve grinding paste into the socket. works a treat