How To Bleed A Hydroboost Brake System
Many new brake system designs use what is known as a hydroboost or hydraulic boost technology. This type of design uses fluid pressure instead of metal pistons like with traditional drum-type brakes. A fluid source is connected to a booster chamber that contains fluid. When you apply foot pressure, the pedal does not fully depress until enough pressure is built up in this chamber. The booster then compresses some of the fluid into the other chambers of the vehicle, creating additional braking force!
This concept was first tried out back in the 1970s on semi trucks, but it did not become popularized until more recent times. Some vehicles now have these types of brakes installed as standard equipment!
There are many benefits to having a hydrailbost brake setup over normal piston-operated disc brakes. First, they can be much lighter and thinner than regular car brake systems due to no need for heavy components such as pistons. Second, there is no risk of dry braking because the fluid will always be present. Third, they do not require any maintenance beyond replacing the fluid every few months.
However, just like anything else, there are drawbacks too! Due to the way they work, they cannot easily correct wheel spin or prevent wheels from locking which could cause accidents. Also, people may develop muscle spasms in their legs due to the longer lever arm needed when applying the same amount of pressure.
Verify that all brake lines are not kinked
The last thing you want to do is use your brakes and find out that there is no fluid in the system! If this happens, then obviously your brake pads are no longer working effectively.
Make sure that none of the lines are kinked or pinched anywhere. This can cause excessive friction which will prevent adequate braking.
You may also need to check the reservoir for moisture/fluid loss. Make sure it is full and clear.
If everything looks okay, try pressing down on the pedal slightly (do not press hard as that could damage the pump) and see if there is still enough braking power.
Verify that all brake pads are not warped
The next thing you will want to do is test your brakes! Test by pumping the pedal down as hard as possible. If they feel good and are working, great! But if there is no response or only a slight improvement, it may be time to look into replacing them!
Brakes can become worn out due to excessive friction or heat. A factor of having too much friction is when one side of the pad sticks to the rotor longer than the other which creates unequal braking. This could also mean that the metal in the rotor has oxidized and fused together, creating a thicker layer of material and reducing efficiency.
To check for this, take off each piece of the wheel slowly so that you do not apply any force on the rotor. Check to see if both sides of the rotor are even. Also, make sure there are no drag marks left from where the brake was locked up before.
If you notice anything abnormal, have your mechanic check out whether or not the brake system needs to be replaced.
Make sure the wheel brakes are not dragging
For example, if your car is in gear with the brake pedal pressed down, this can quickly cause overheating of the braking system.
This happens because the wheels do not have enough friction with the surface to slow down the vehicle! As such, the engine has to work harder which costs money and energy.
To prevent this from happening, make sure that when you pull out of a parking lot or driveway, you allow for some drag. This helps reduce how fast you will be able to come to a stop!
Another way to ensure adequate slowing is by using proper torque settings on all four wheels.
Confirm that the bike is upright and not moving
Once you have verified that your brake is working and the wheels are still, it is time to begin bleeding your brakes!
To do this, first make sure that the handlebars of the bicycle are at a comfortable position for riding. If they are too low or too high, then feel free to adjust them so that when you apply pressure with your hands, there is adequate room for applying torque (turning force) with the pedals.
Next, pull the lever all the way up until there is no longer any fluid coming out. This may take several pulls as the hydrostatic pump will not quickly empty. When there is only very little fluid left, remove the bleeder screw completely!
Now push down hard on the piston using a tool such as a heavy hammer or even your hand. Make sure nothing is hooked onto the brake system, otherwise you could lose parts or damage the unit!
Once pressed down, turn the wheel slightly so that some slack is taken off of the braking system. Apply light pressure and see if the pedal turns without much resistance. You can now release the pressure fully and the bikes brakes should hold steady!
Removing most of the hydraulic fluid from the brake will reduce their effectiveness temporarily, but will also expose the pistons to air which allows for more efficient cooling.
Test the brake system by squeezing the levers firmly
The second way to test your brakes is by using the index finger method. This can be done at any time, not just while braking!
To perform this test, place your pointer (index) finger over the front lever of the wheel. Now push down hard with all your might. If the pedal goes up then the brakes are working properly.
You can also feel whether or not there is enough friction in the brakes by how firm the pedal is. A soft pedal indicates that the brakes need work and should be checked out more thoroughly.
Wipe down the components with rubbing alcohol
After cleaning off the shoes, next up is the booster plate. Use warm soapy water or paper towels to wipe it clean. Once cleaned, use an old thin piece of plastic or cardboard as a cover until you can put the plate in its proper container.
Next, wash the caliper body and hose out using hot, not boiling, water. This will remove any dirt or moisture that may have dried onto them. Make sure to dry each part completely before assembling back into the system.
Dip parts such as the piston in a solution of baking soda and vinegar to help prevent corrosion.
Loosen the brake pads and wipe down the rotor
The next step in bleeding your brakes is to loosen the friction discs or brake pads that are attached to the wheel. You can do this by using a tool called an adjustable torque wrench.
Most automotive manufacturers design their cars such as Honda with easy access to changing brake shoes or pads, so it’s not too difficult to work with them. For more exotic vehicles though, it may be harder to change the brakes so make sure you have a good amount of idle time before heading out!
Once you have loosened the pad, now it’s time to clean off the rotor (the part of the disc where braking takes place). Since most people don’t have special equipment for this, we will go over some tips here.
Don’t use soap to remove dirt from the rotor, instead use rubbing alcohol or acetone.
Disassemble the brake pads and clean them
After you have removed the rotor, wash it off with water and use a brush to remove any residue or dirt. If there is no brush available, you can use your fingernail to scrape away debris.
Once everything has been washed, put the brakes back together! Make sure that you do not forget anything as this could cause damage to the pistons or other components of the system!
After putting all parts back into place, make sure they fit properly and are able to move easily in both position and rotate. Test out the braking ability of the vehicle by taking some tight turns at low speeds.