Tips on removing a rusted-out rear caliper?

[CheeseHelmet]

I'm in the process of changing my rear disks and rotors but I'm stuck...

The rust is terrible; I've already broken the bolt that holds the parking brake bracket onto the caliper and now I can't seem to get off the 10mm bolt that holds the caliper onto the "Mounting Support" (I've also seen it referred to as the "shoe").

Do you guys have any tips for this job?

 

[MaxPower]

Try some PB Blaster to loosen the rust. Blast the bolt and let it sit. Also, use a 6-point socket instead of a 12-point to reduce the chance of rounding the bolt. And, of course, use the longest breaker bar you can.

Chances are the rotor will be rusted on, too. On the hat of the rotor is a small hole. Put an M8 bolt in there and turn until the rotor pops off. You can also spray some PB Blaster into the hole to loosen the rust. Gentle hammering can help a bit, too.

 

[P-Funk!]

Spray with PB Blaster and let it soak.

Hit the wrench with a hammer to break it loose (if possible)

 

[CheeseHelmet]

I sprayed it with PB blaster about an hour ago but I doubt it'll do much, there aren't many openings to spray into.

Also, I should have mentioned that the bolt head is already semi-rounded because of all the rust. I suspect I'll be resorting to using vice grips...

 

[msp5]

Hit the caliper mounting bracket with some heat, being careful not to cook the dust boot.

 

[drgnzadiel101]

spray with pb blaster and let it soak.

Hit the wrench with a hammer to break it loose (if possible)

+1

 

[CheeseHelmet]

Thanks for all the suggestions. I used all of them in one form or another (except heat, I didn't want to melt anything).

I ended up breaking one bolt (the one that holds the parking brake cable bracket to the caliper) but it shouldn't be all that hard to drill and tap a new hole. The others came out after using a lot of PB blaster and waiting. Oddly enough, the passenger side caliper was quite easy to remove; after a bit of forcing with the breaker bar they all broke free.

 

[msp5]

make sure to use antiseize on the bolts and brake lube in the slide pins

 

[CheeseHelmet]

make sure to use antiseize on the bolts and brake lube in the slide pins

Heh, I've got bigger problems. The caliper is seized pretty bad on the slide pin so I'm trying to figure out how to get that off ATM...

 

[CheeseHelmet]

Never mind, I just wasn't using a big enough hammer

Next up is the bleeder screws; I'm gunna let them soak in PB blaster until tomorrow, hopefully they'll come loose.

 

[ornithology]

Pics if you can!

 

[CheeseHelmet]

Pics if you can!

Pics of what?

Anyway, to keep you guys up to date... One of the bleeders broke when taking it out. I tried using an easyout with no luck, then I drilled and tapped the hole but the bleeder leaked when I tightened it. Then I tried some other useless s***, and now I'm waiting till Monday to go buy a re-manufactured caliper.

If anyone wants some good guides on changing pads and rotors, see:

• How-To: Complete Brake Service by rainierez
• Mazda Proteg5 Brake Overhaul from thinkythings.org