I just compressed the calipers for a brake job and both had a small bulge where the boot did not collapse all around the piston. Is this normal or a bad sign?
Thanks.
Thanks.
Caliper boot had a small bulge when reset
- Thread starter ProfPS
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Normal. I run a pic around the boot to help seat it.
Originally Posted By: Chris142
Normal. I run a pic around the boot to help seat it.
On my last Caravan job I had trouble getting one boot to retract correctly. I discovered the problem was from air trapped under the boot. Using a pick where the boot attaches to the piston allowed the air to escape and the boot to retract normally.
You may have to carefully pump the piston partially out and then re-collapse the piston, using the pick to relieve the air pocket.
My 2 cents. Best of luck!
Normal. I run a pic around the boot to help seat it.
On my last Caravan job I had trouble getting one boot to retract correctly. I discovered the problem was from air trapped under the boot. Using a pick where the boot attaches to the piston allowed the air to escape and the boot to retract normally.
You may have to carefully pump the piston partially out and then re-collapse the piston, using the pick to relieve the air pocket.
My 2 cents. Best of luck!
Thanks for the responses. I made the mistake not to remove the master cylinder cap when I collapsed the calipers. If the bulge remains, will it cause a problem?
Originally Posted By: doitmyself
Originally Posted By: Chris142
Normal. I run a pic around the boot to help seat it.
On my last Caravan job I had trouble getting one boot to retract correctly. I discovered the problem was from air trapped under the boot. Using a pick where the boot attaches to the piston allowed the air to escape and the boot to retract normally.
You may have to carefully pump the piston partially out and then re-collapse the piston, using the pick to relieve the air pocket.
My 2 cents. Best of luck!
Be very careful with a pick. Wood or plastic is safer than metal.
Originally Posted By: Chris142
Normal. I run a pic around the boot to help seat it.
On my last Caravan job I had trouble getting one boot to retract correctly. I discovered the problem was from air trapped under the boot. Using a pick where the boot attaches to the piston allowed the air to escape and the boot to retract normally.
You may have to carefully pump the piston partially out and then re-collapse the piston, using the pick to relieve the air pocket.
My 2 cents. Best of luck!
Be very careful with a pick. Wood or plastic is safer than metal.
My brake expertise is based on modest personal experience and what I learn elsewhere (books, web, mechanic friends). In other words, don't depend on my advice!
I am not sure how removing the master cylinder cover would affect your current problem.
My understanding of disk brakes (someone correct me) is that there is no return spring to retract the pads/piston and that the shape and design of the piston o ring seals (not protective boot)results in a TINY retraction of the piston.
To me, if your caliper boot is not seated correctly, I would fear that it could impose a TINY amount resistance in the piston movement that MIGHT affect the TINY amount of retraction that is caused by the o ring seals.
Just my understanding of things. But, I would make sure the boot is seated as it was designed.
And yes user52165, thanks for clarifying the need to use a blunt tool to poke around the boot. I had to order a new OEM boot from the dealer once because of impatient use of a screwdriver!
I am not sure how removing the master cylinder cover would affect your current problem.
My understanding of disk brakes (someone correct me) is that there is no return spring to retract the pads/piston and that the shape and design of the piston o ring seals (not protective boot)results in a TINY retraction of the piston.
To me, if your caliper boot is not seated correctly, I would fear that it could impose a TINY amount resistance in the piston movement that MIGHT affect the TINY amount of retraction that is caused by the o ring seals.
Just my understanding of things. But, I would make sure the boot is seated as it was designed.
And yes user52165, thanks for clarifying the need to use a blunt tool to poke around the boot. I had to order a new OEM boot from the dealer once because of impatient use of a screwdriver!
Originally Posted By: ProfPS
I just compressed the calipers for a brake job and both had a small bulge where the boot did not collapse all around the piston.
If you mean the dust boot that surrounds the piston, it's normal; but it should be corrected so as not to risk tearing the boot when you put everything back together again.
Just push the bulge back in place with your finger or a Popsicle stick or other blunt instrument.
I just compressed the calipers for a brake job and both had a small bulge where the boot did not collapse all around the piston.
If you mean the dust boot that surrounds the piston, it's normal; but it should be corrected so as not to risk tearing the boot when you put everything back together again.
Just push the bulge back in place with your finger or a Popsicle stick or other blunt instrument.
When assembled and seated , are there any anomalies?
This is what counts.
This is what counts.
Finished putting everything together this evening and took it for a test drive. Made a few slow a steady stops and increased pedal pressure to burnish the pads & rotors and check for any leaks. Got them warmed up then drove a couple miles without using the brakes to check for a hanging caliper. Everything cooled down and seems to be working okay. I'll drive it tomorrow in traffic.
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