How to change seals/boots on your front brake calipers

mooch91

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Did this job myself tonight as part of my complete brake service, found it quite quick and easy and took some pictures. Thought I'd share.

Seems the boots are prone to degradation on our calipers. I'm sure the seals on mine were fine, but it's part of the job to replace them. You can see the condition of the boots on mine, caliper removed from the car:
DSCN3819_zpsd7874c58.jpg


The replacement parts I used. Only one set of seal/boot per package, two packages required for each caliper:
DSCN3831_zps1af57197.jpg


First thing is to remove the pistons from the caliper. A little bit of pressure works well here. Wear safety glasses and insert a block between the pistons and the other side of the caliper to prevent the pistons from flying out like the projectiles they will become. A 2x4 is a little bit too big to allow the pistons to pop out enough. I started with a 2x4 and ended with a sanding block I had around:
DSCN3821_zps20d13ecf.jpg

DSCN3822_zps6d5b6235.jpg

DSCN3823_zpsc0fb5d37.jpg


Wiggle the pistons out the rest of the way and remove and discard the boots. Here you can see how much dirt/grit can get in there, even with in-tact seals:
DSCN3826_zps9c8b1d42.jpg


Next step is to pop out the seal with a dental pick:
DSCN3827_zpsb6a63bc2.jpg


Seals out, throw them away too:
DSCN3828_zps272eb869.jpg


The caliper bores also look pretty dirty:
DSCN3829_zpsc0ac50d3.jpg


Use some brake cleaner to clean up the pistons, real well, spotless:
DSCN3830_zpsd25a5b68.jpg


Clean up the bores with brake cleaner as well:
DSCN3838_zpsde11576b.jpg


Install the new seals. They slip right in to the ridge inside the bore. Lubricate the seals and the bores extremely well with fresh brake fluid in doing so.
DSCN3839_zpsc01d9de4.jpg

DSCN3840_zpsebb530ff.jpg


Installing the new boots was the tricky part of the job. There seems to be one easy way, a trick if you will, for getting the boots on properly. Start by slipping the new boot (in the correct direction (wider diameter down, narrower diameter up) over the top of the piston:
DSCN3833_zps88d8098b.jpg

DSCN3834_zpsb1b6bb03.jpg


Slide it down beyond the ridge where it will sit in the piston:
DSCN3835_zps3fdc7656.jpg

DSCN3836_zps8f7d9268.jpg


And actually hang the wider diameter end over the bottom of the piston:
DSCN3837_zps6a02522a.jpg


Lubricate the piston up real well with brake fluid. Begin to re-insert the piston by installing the wider diameter of the boot in to its detent in the bore. Start at the point of the bore on the closed side of the caliper since you won't have access to this side once you get the piston moving in place. When you've got it, you know it - you can actually spin the boot in its detent with very little resistance. It's important to lock the boot in its detent before trying to insert the piston:
DSCN3841_zps9b2baa07.jpg

DSCN3842_zpse4e198cd.jpg


Now you can start to insert the pistons, gently and evenly, in to the bore. Make sure they don't go in cocked at an angle:
DSCN3844_zps3c056f18.jpg


Push the pistons in until the narrower diameter of the boots snap in to the detent in the piston. They should be bottomed out in the bore. Check to see that the boot is properly seated around the piston:
DSCN3845_zps7b4b8cbf.jpg


Clean your caliper up with some etching wheel acid (I used Eagle One Mag Wheel Cleaner) and it's just about ready for paint. Paint them after the seal and boot replacement; the brake fluid you encounter would almost certainly ruin the paint:
DSCN3846_zps9852a7b2.jpg
 
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mooch91

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I had no problem with it. It's just a mild etching acid. I suppose you could clean it before you begin the disassembly and then finish up the process with some brake cleaner to get rid of any residual brake fluid before paint.
 

HwyKng

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Thanks for sharing. Good stuff you have there. Im sure there are a ton of members that would like to do this.
 

mooch91

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What kind of paint did you use? That looks very nice.

VHT satin black caliper paint.

I baked (as suggested on the can) with a combination of the sun and a high-temp halogen work lamp before reassembly.

You have to be incredibly careful - although it says "chemical resistant", it seems as if brake fluid can still do a number on it, even if cured.

I'm hoping temps of braking will help it to cure further. Nonetheless, when I reconnected and bled the brakes, I was extremely careful not to get any on the caliper.

So far, so good. And I'm happy I had to take them off anyway so it was a no-brainer to spray the "off the car". I think I got better coverage and a cleaner look.

New rotors are Centric brand; they already had a satin black finish on the hat and edges, so it matches well.
 

bwahl602

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i was thinking about having some calipers powder coated.. anyone know if brake fluid will eat powder coating?

looks great
 

no cigar

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Hey fellas I finally got around to taking the calipers in to have the pistons blown out. Problem is only one piston came out of each caliper. Is it safe to grab the piston with channel locks or something and pull it out?
 

99lightning_svt

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Hey fellas I finally got around to taking the calipers in to have the pistons blown out. Problem is only one piston came out of each caliper. Is it safe to grab the piston with channel locks or something and pull it out?

As long as you dont leave marks or warp it in some way you should be fine. I just put the one that came out back in just enough to hold pressure and block it so it cant move then blow the other one out.
 

1Kona_Venom

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TY...been lookin around for a how to Ill be getting mine powdercoated then reassemble....but wasnt sure about the pistons and what not

again thanks:rockon:
 

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