Summary
The piston is an integral part of the brake caliper. To help in stopping your car, the piston is in charge of bringing the brake pad into contact with the brake rotor. A corroded or rusted caliper piston, brought on by a defective piston boot, is usually to blame when the brake caliper piston fails to compress.
There are one, two, four, or six pistons needed for a brake caliper. Each piston was designed to enable the caliper to balance, applying an equal amount of pressure to all the brake pads.
There are several symptoms you may start to notice if your caliper pistons are failing. When you try to brake, you frequently get a dragging sensation. The piston doesn’t completely retract when you let go of the brake pedal because it is stuck in the bore. When you press down on the brake pedal, you can also notice that it feels spongy or mushy. This is yet another sign of a stuck piston.
The causes caliper piston won’t compress are corrosion, worn boots, or seals, broken brake hose, incorrect wind back procedure, and inactive of the vehicle.
Now, let’s go deep to explain causes caliper pieson won’t compress, prevention, and how to fix!
Contents
What causes the caliper piston not to compress?
Here are the most common causes for caliper piston that won’t compress:
Corrosion
The most common and possible reason why your caliper piston won’t compress is due to corrosion or rust. Most typically, corroded or rusted caliper pistons are to blame for the caliper piston’s inability to function because of a damaged caliper piston boot.
Generally speaking, corrosion can make the front wheels rub when driving or keep the brake calipers from working properly. You should be aware that even a little amount of rust might affect how well it compresses.
Worn Boot or Seals
The piston seals deteriorate with time. The seals will eventually stop functioning altogether, keeping the piston from moving. It might also be connected to the piston’s protective and lubricating rubber boot. Water will enter the piston as the rubber tears or deteriorates, causing the piston to lock up.
Broken brake hose
A broken brake hose is another possible cause of the brake caliper sticking. Brake fluid leaks onto the piston if the hose begins to crack or break. The caliper will become stuck since it can’t return to the master cylinder, where it belongs.
Sometimes, though, the caliper itself isn’t actually stuck. The brakes may occasionally feel the same as they did before the hose broke. To find the source of the issue, carry out an inspection.
Incorrect Wind Back Procedure
It is likely that you are not following the service procedure’s directions if the problem is with the rear caliper. Remember that the operation of the front and rear calipers differs. To compress them, you must adhere to the correct steps.
Undoubtedly, it is difficult to push the rear calipers in. You must simultaneously press and twist them. Additionally, using a wind-back tool is a good way to use them. Rewinding your parking brake might need a diagnostic tool if it’s electric. Always keep an eye out for additional damage signs, such as both front brake calipers that won’t release.
Inactivity of the Vehicle
Another possibility of the caliper piston not compressing is the inactivity of the vehicle. If you drive your vehicle regularly, you might not experience this problem. On the other hand, leaving your car unattended for several months might foster the ideal conditions for rust and corrosion.
The caliper cannot fully compress as a result of the rust that has developed on it, which can cause your car to struggle to move.
How do you fix a caliper piston that won’t compress?
Here’s how to compress a seized caliper piston:
Piston Compression Tool
Using a piston compression tool can make the task of compressing a caliper piston much simpler. It’s important to ensure that the compressor is properly configured for the specific brake system you are working on. Additionally, make sure that the push bar of the compression tool is not left protruding. Place the front caliper compressor next to the front caliper and install the brake pads.
Then, use the compression tool to apply pressure to the caliper piston, which should cause it to retract and compress. However, keep in mind that compressing a caliper piston can be a delicate process and requires a specialized tool, so it’s recommended to have a professional mechanic perform this task if you are not confident in your abilities.
C-Clamp
A basic C-clamp can be used as an alternative to a piston compression tool to compress a caliper piston. Place the C-clamp on the caliper with the screw positioned at the end of the piston. To prevent damage to the piston surfaces, it’s recommended to use a piece of hardwood between the C-clamp and the piston.
Slowly tighten the screw to apply pressure to the piston and compress it. However, it’s important to be cautious when using a C-clamp, as applying too much pressure too quickly can cause damage to the caliper or brake system. Additionally, C-clamps are not as precise as specialized piston compression tools, so it’s recommended to use a compression tool if possible.
Channel Locks
Channel locks can be used as an alternative to a piston compression tool to compress a caliper piston. To use channel locks, place one end behind the caliper and the other end behind the brake pad. Make sure that the brake caliper and pad are positioned halfway between the grips of the channel locks.
When you squeeze the channel locks together, they should compress the piston. However, it’s important to apply pressure gradually and carefully, as applying too much pressure too quickly can cause damage to the caliper or brake system. Additionally, channel locks are not as precise as specialized piston compression tools, so it’s recommended to use a compression tool if possible.
How do you prevent a caliper piston from not compressing?
Maintaining clean caliper pistons is the best way to prevent them from seizing up. Use the time you have when changing your brake pads to use some brake cleaner and a brush to clean up the piston bores.
By doing this, any dirt and debris that can cause the pistons to stick will be removed. After cleaning the bores, you can also blow them out with compressed air. Making sure your caliper pistons are properly oiled is another technique to prevent them from not compressing.
Apply a thin coating of lubricant to the piston bores while changing your brake pads. The pistons will be able to move more easily and won’t stick as a result of this.
Can you drive even if the caliper piston won’t compress?
It’s not safe to drive a vehicle if the caliper piston won’t compress. The caliper piston, a crucial part of the braking system, is in charge of exerting pressure on the brake pads in order to create the friction that slows and stops the car.
The brakes may not function properly if the caliper piston fails to compress, which could indicate that there is a problem with the braking system.
This could make stopping the car difficult or impossible, which can be dangerous. It is advised that you take your car to a qualified mechanic as soon as possible for an inspection if the caliper piston is causing you problems.
They will be able to identify the issue and carry out the required fixes to ensure that the brakes on your car are in good working condition. Learn about brake caliper here!
https://studentlesson.com/understanding-brake-caliper/
Conclusion
In conclusion, a variety of problems, including seized caliper slides, brake fluid blockages, or damaged caliper seals, can be responsible for a caliper piston that won’t compress. Neglecting this issue might compromise brake performance and safety. To maintain effective and safe brake functioning and ensure dependable stopping force when required, the primary cause must be promptly addressed through inspection and any necessary repairs or replacements.
It’s important to realize that a non-compressing caliper piston can lead to further problems with your car’s braking system. It not only limits your ability to stop quickly, but it also produces excessive heat that could harm the rotors and diminish the effectiveness of your brakes as a whole.
It is crucial to tackle this issue right now. Start by doing a complete inspection to determine the underlying problem. This inspection may involve looking for obstructions in the brake lines, examining the caliper slides for rust or debris, and checking the caliper seals.
A non-compressing caliper piston that is neglected can lead to dangerous driving conditions, higher repair expenses, and even dangerous situations on the road. Recognizing the importance of giving this problem immediate attention emphasizes your dedication to vehicle safety and good vehicle maintenance.
That is all for this article where I explained causes caliper pieson won’t compress, prevention, and how to fix. I hope you learn a lot from the reading. If you do, kindly share it with others. Thanks for reading, see you around!
