Procedures

Rebuilding the Saab 9000 front brake calipers


By GirlySaabFan

Introduction

The Saab 9000 front brake calipers are quite simple parts but the rubber parts can deteriorate with consequent degradation of the piston. The following procedure applies to both types of front caliper fitted to the Saab 9000, as well as the front caliper fitted to rear-handbrake Classic 900 models.

(All the parts replaced in this procedure are available here)



There are two ways of removing the piston.  If you have access to a compressor, then that is probably the least messy way of doing it.  The other way is to push the piston out using the foot brake.
 
Foot brake method:
 
Remove the caliper and pads from the carrier but leave the hose connected. Tie the caliper up, so the hose isn't under strain and place a suitable container underneath or put a bag over the caliper to catch the piston and the quantity of brake fluid that will follow.  Have lots of rags handy!  Slowly pump the brake pedal until you hear the piston pop out, clamp the hose, disconnect the hose from the caliper and collect the piston from wherever it landed!
 
Compressed air method:
 
Remove caliper and pads, disconnect hose and blow the air into the inlet.  Have the caliper in a box or bag to catch the piston and brake fluid.
 
Eye protection is strongly recommended.
 
If the piston is very tight, try pushing it back in to free it up.
 
Once you have the piston out, clean it and the caliper bore out and check for pitting and scoring.  If this is excessive then you need to replace the piston or scrap the caliper, or both. A replacement piston is available here.

 
Clean out crud from caliper and piston.
 
 front_caliper1.jpg
front_caliper2.jpg

Check for damage. If the part below groove is corroded or badly scratched, it should be replaced. A replacement piston is available here.

 front_caliper3.jpg
 
Remove dust boot and seal and clean up the grooves.  The boot should just pull out if you're careful and the seal can be lifted out of it's groove using a small screwdriver.

  front_caliper4.jpg

All the parts I replaced are available from here.

Once you're satisfied the grooves are clean, dip the seal in brake fluid and fit into the innermost groove

 front_caliper5.jpg

Fit the dust boot to the groove in the top of the piston, making sure it is seated all the way round.

front_caliper6.jpg
 
Fit the piston into the bore.  It should slide in by hand with firm pressure, if it doesn't, don't force it as it's not going in straight.  Straighten it up and try again.  Once it's in, carefully push the bottom edge of the boot down into it's groove using a small screwdriver or similar.  Be careful not to tear the boot.  It's easier if you start at the side nearest to the body of the caliper and work outwards.

 front_caliper7.jpg

The boot should fit flush.

front_caliper8.jpg
 
Replace the dust covers for the sliding pins if necesary and refit caliper to car.
 
Don't forget to bleed the brakes!