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[html:2pp5pd7r]<p align="center"><font size="6"><b>How to Bleed Brakes – The <i>Right </i>Way</b></font></p>
<p class="copyHeading"><b>Brake System Basics</b></p>
<p class="copy">The workings of the brake system may, at first glance, seem
obvious: we push on the brake pedal, which clamps the pads onto
the rotor, which stops the car, right? But think further: a
2400-pound vehicle in motion possesses a great amount of kinetic
energy (the energy of motion.) And the laws of physics dictate
that energy cannot be created or destroyed. So what happens to
all of the kinetic energy from a moving vehicle when the vehicle
stops?</p>
<p class="copy">Since the energy cannot be destroyed, then it must be
converted into something else. In this case, it is converted into
heat. And it is this conversion process that is the true function
of the braking system. <i>Brakes convert kinetic energy into heat
energy through friction</i>. And once all of a vehicle’s
kinetic energy has been converted, the vehicle stops – since
it has no more kinetic energy – and ends up with lots of
heat energy. This heat energy is created as a result of friction
between the brake pad and the rotor (or the shoe and the drum,)
briefly stored in the rotor (or drum,) and eventually dissipates
into the surrounding air. </p>
<p class="copy">But how does the input of force at the brake pedal (from our
foot) result in clamping force – and hence friction -
between the brake pads and the rotor? Like most of the functions
of a modern car, the operation of the "brakes" is
actually part of a larger integrated "system." And
while there are many important parts of the braking system,
suffice it to say that brake fluid is a <i>very</i> vital
component within the system. </p>
<p class="copy">In a nutshell, when we apply force to the brake pedal with our
leg, this force is increased (thanks to the lever law) based upon
the length of the brake pedal lever. This force moves through the
vacuum booster – where it gets amplified by the motor’s
vacuum – and finally gets transferred into the piston within
the master cylinder. The force against the piston in the master
cylinder pushes the piston into brake fluid. The fluid is then
forced through the brake pipes toward the brake components at the
corners of the car. Finally, the fluid pushes against the piston
within the brake caliper - which clamps the brake pads against
the rotor.</p>
<p class="copy">Clearly, the fluid is vital – since we depend upon the
liquid properties of the fluid to transfer force through the
system into the brakes at the wheels. In theory, since a liquid
cannot be compressed, we can count on the hydraulic actuation to
result in a linear transfer of forces. (In other words, we do not
expect liquid to compress. If it did compress, then we would
"waste" energy compressing the fluid instead of using
the energy to create movement at the brake corners.)</p>
<p class="copy">In summary, the role of the brake fluid within the braking
system is to transfer the force from the master cylinder to the
corners of the car. And a vital characteristic of brake fluid
that allows it to perform its task properly is its ability to
maintain a liquid state and resist compression.</p>
<p class="copyHeading"><b>Why Bleed the Brakes?</b></p>
<p class="copy">The term "bleeding the brakes" refers to the process
in which a small valve is opened at the caliper (or drum) to
allow controlled amounts of brake fluid to escape the system.
(When you think about it, "bleeding" may appear to be a
somewhat graphic term, but it aptly describes the release a vital
fluid.)</p>
<table border="0" cellpadding="4">
<tr>
<td><font color="#FF0000" size="2">*Note: technically,
"air" only enters the lines if there is a
compromise of the system’s sealing (as when flex
lines are removed or replaced.) When fluid boils, it will
instead create "fluid vapor." Vapor will create
an equivalent efficiency loss. But we use the term
"air" here for simplicity.</font></td>
<td>We bleed the brakes to release air<font color="#FF0000">*</font> that sometimes becomes trapped
within the lines. When air becomes present within the
lines, it creates inefficiencies within the system
because, unlike liquid, air can be compressed. So when
enough air fills the lines, input at the pedal merely
causes the air to compress instead of creating movement
at the brake corners. In other words, when air is present
within the system, the efficiency and effectiveness of
the braking system is reduced. Usually, a small amount of
air within the brake system will contribute to a
"mushy" or "soft" pedal (since less
energy is required to compress the air than is required
to move fluid throughout the brake lines.) If enough air
enters the brake system, it can result in complete brake
failure.</td>
</tr>
</table>
<p class="copy">So how does air enter the lines in the first place? Sometimes,
it can be the result of a service procedure or an upgrade –
such as replacing the stock flex lines with stainless steel
braided lines. But often it is the result of high temperatures
that cause brake fluid components<font color="#FF0000"> </font>to
boil, thus releasing gasses from the boiling fluid into the brake
pipes.</p>
<p class="copyHeading">Brake Fluid Selection</p>
<p class="copy">This leads one to contemplate the type of liquid that is used
as brake fluid. In theory, even simple water would work –
since, being a liquid, water cannot be compressed. However, it is
important to remember that the fundamental function of the
braking system is to convert kinetic energy into heat energy
through friction. And the reality of this process is that certain
parts of the braking system will be exposed to very high
temperatures. In fact, testing on the scR showroom stock racecar
has shown that rotor temperatures during a race will become as
high as 1100 degrees Fahrenheit.<font color="#FF0000">*</font>
Since the boiling point of water is 212 degrees Fahrenheit, it is
easy to see that water within the brake system could boil easily
– and therefore release gases into the brake pipes –
which will reduce the efficiency of the system. (Water would also
present a big problem in cold weather if it froze to ice!)</p>
<table border="0" cellpadding="4">
<tr>
<td>The "obvious" solution to this problem is
to utilize a fluid that is less sensitive to temperature
extremes. Hence the development of "brake
fluid." However, there unfortunately is no such
thing as a "perfect" brake fluid. And like most
things in the world, the addition of certain beneficial
characteristics usually brings tradeoffs in other areas.
In the case of brake fluid, we generally must balance the
fluid’s sensitivity to temperature against its cost
and its impact upon other components within the system.</td>
<td><font color="#FF0000" size="2">*Note: Even though the
rotor gets very hot, the brake fluid will never see such
high temperatures – since the heat must be passed
through the brake pad, caliper, piston, and other
components. Most of the heat will dissipate along this
route before reaching the brake fluid. Previous testing
has indicated that a rotor temp between 800-900 degrees
Fahrenheit can result in a fluid temperature closer to
300 degrees Fahrenheit – still enough to boil water!</font></td>
</tr>
</table>
<p class="copy">Stated more bluntly, it is possible to reduce a fluid’s
sensitivity to temperature by varying the ingredients of the
fluid. However, certain combinations of ingredients can
significantly increase the cost of the fluid and may react with
OEM materials to damage seals and induce corrosion throughout the
braking system.</p>
<p class="copy">The chemical composition and minimum performance requirements of the fluid are generally
indicated through a rating such as "
OT3," DOT4,"
or "OT5." The DOT-rating itself is assigned after a
series of government tests. However, this rating is NOT intended
to indicate boiling points, even though higher DOT ratings
generally do correspond with higher boiling points. Perhaps more
importantly, the DOT rating <i>does</i> indicate the base
compound of the brake fluid - which allows manufacturers to
specify fluid types which are less likely to react negatively to
known materials used within a particular braking system.</p>
<p class="copy">The greatest irony about brake fluid, however, is the fact
that the chemical compositions that tend to be less sensitive to
temperature extremes also tend to attract and absorb water! So
even though the fluid <i>itself </i>is unlikely to boil (most
glycol-based DOT3 fluids have a "dry boiling point"
around 400 degrees Fahrenheit,) the water that it absorbs over
time tends to boil easily (at 212 degrees Fahrenheit.) It is this
characteristic of absorbing moisture that leads to the measure
known as the "wet boiling point." The wet boiling point
is the equilibrium boiling point of the fluid after it has
absorbed moisture under specified conditions. Because brake fluid
will absorb moisture through the brake system’s hoses and
reservoir, evaluation of the wet boiling point is employed to
test the performance of <i>used</i> brake fluid and the
degradation in it’s performance. (And it is why we still
need to bleed the brakes frequently on the racecars, even though
we use AP600 racing fluid that costs $18 per bottle!) The lesson:
do NOT expect to avoid bleeding your brakes just because you
bought expensive brake fluid.</p>
<p class="copy">As one might guess, "racing" fluids will use
relatively "aggressive" chemical compositions which
will tend to have higher wet boiling points and higher costs,
while the average street fluids will use more conservative compositions which will have lower wet
boiling points and lower costs. In some cases – such as a
purpose-built racecar – the tradeoffs of using the expensive
racing fluid is outweighed by the competitive advantages. But for
the average driver – whose driving style is less likely to
induce very high brake temps – the costs of the fluids and
potential wear-and-tear factors upon system components may
justify the use of a more conservative fluid with a lower wet
boiling point.</p>
<p class="copyHeading">The Proper Bleeding Procedure</p>
<p class="copy"><b>Supplies Preparation</b></p>
<p class="copy">You will need the following tools:</p>
<ul>
<li>10mm box-end wrench (8mm for rear drum brake units.) An
offset head design works best.</li>
<li>Extra brake fluid<font color="#FF0000"> </font>(1 pint if
you are just bleeding, 3 if you are completely
replacing).</li>
<li>14-inch long section of 3/16 in. ID clear plastic tubing.</li>
<li>Disposable bottle for waste fluid.</li>
<li>One can of brake cleaner.</li>
<li>One assistant (to pump the brake pedal.)</li>
</ul>
<p><b>Vehicle Preparation and Support</b></p>
<ol>
<li>Loosen the lug nuts of the road wheels using a 19mm
socket and place the entire vehicle on jackstands. Be
sure that the car is firmly supported before going <b><i>ANY</i></b>
further with this installation! </li>
<li>Remove all road wheels.</li>
<li>Install one lug nut backward at each corner and tighten
the nut against the rotor surface (to limit flex that may
distort pedal feel.)</li>
<li>Open the hood and check the level of the brake fluid
reservoir. Add fluid as necessary to ensure that the
level is above the seam of the reservoir. Do not let the
reservoir become empty during the bleeding process.</li>
</ol>
<p class="copy"><b>Bleeding Process</b></p>
<ol>
<li>Begin at the corner furthest from the driver and proceed
in order toward the driver. (Right rear, left rear, right
front, left front.)</li>
<li>Locate the bleeder screw at the rear of the caliper body
(or drum brake wheel cylinder.) Remove the rubber cap
from the bleeder screw.</li>
<li>Place the box-end wrench over the bleeder screw (10mm for
discs, 8mm for drums.) An offset wrench works best –
since it allows the most room for movement. (If you do
not have an offset wrench, avoid pushing the wrench head
to the bottom of the bleeder screw – since the
wrench may interfere with other parts during movement.
Allow a standard wrench to sit near the top of the
bleeder screw contact point.)</li>
<li>Place one end of the plastic hose over the nipple of the
bleeder screw.</li>
<li>Place the other end of the hose into the disposable
bottle.</li>
<li>Place the bottle for waste fluid on top of the caliper
body or drum unit. Hold the bottle with one hand and
grasp the wrench with the other hand.</li>
<li>Instruct the assistant to "apply." The
assistant should pump the brake pedal three times, hold
the pedal down firmly, and respond with
"applied." Instruct the assistant not to
release the brakes until told to do so.</li>
<li>Loosen the bleeder screw with a brief ¼ turn to release
fluid into the waste line. The screw only needs to be
open for one second or less. (The brake pedal will
"fall" to the floor as the bleeder screw is
opened. Instruct the assistant in advance not to release
the brakes until instructed to do so.) </li>
<li>Close the bleeder screw. </li>
<li>Instruct the assistant to "release" the brakes.
Note: do NOT release the brake pedal while the bleeder
screw is open, as this will suck air into the system! </li>
<li>The assistant should respond with "released."</li>
<li>Inspect the fluid within the waste line for air bubbles.</li>
<li>Continue the bleeding process (steps 11 through 16) until
air bubbles are no longer present. Be sure to check the
brake fluid level in the reservoir after bleeding each
wheel! Add fluid as necessary to keep the level above the
seam line.</li>
<li>Move systematically toward the driver – right rear,
left rear, right front, left front - repeating the
bleeding process at each corner. </li>
<li>When all four corners have been bled, spray the bleeder
screw (and any other parts that were moistened with
spilled or dripped brake fluid) with brake cleaner and
wipe dry with a clean rag. (Leaving the area clean and
dry will make it easier to spot leaks through visual
inspection later!) Try to avoid spraying the brake
cleaner DIRECTLY on any parts made of rubber or plastic,
as the cleaner can make these parts brittle after
repeated exposure. </li>
<li>Test the brake pedal for a firm feel. (Bleeding the
brakes will not necessarily cure a "soft" or
"mushy" pedal – since pad taper and
compliance elsewhere within the system can contribute to
a soft pedal. But the pedal should not be any worse than
it was prior to the bleeding procedure!)</li>
<li>Be sure to inspect the bleeder screws and other fittings
for signs of leakage. Correct as necessary.</li>
<li>Properly dispose of the used waste fluid as you would
dispose of used motor oil. <font color="#FF0000">Important:
used brake fluid should NEVER be poured back into the
master cylinder reservoir! </font></li>
</ol>
<p><b>Vehicle Wrap-Up and Road Test</b></p>
<ol>
<li>Re-install all four road wheels. </li>
<li>Raise the entire vehicle and remove jackstands. Torque
the lug nuts to 140 Nm (103 ft-lb) using a 19mm socket.
Re-install any hubcaps or wheel covers also using a 19mm
socket.</li>
<li>With the vehicle on level ground and with the car NOT
running, apply and release the brake pedal several times
until all clearances are taken up in the system.</li>
<li>Road test the vehicle to confirm proper function of the
brakes. <b><i>USE CAUTION THE FIRST TIME YOU DRIVE YOUR
CAR AFTER MODIFICATION TO ENSURE THE PROPER FUNCTION OF
ALL VEHICLE SYSTEMS!</i></b></li>
</ol>[/html:2pp5pd7r]
<p class="copyHeading"><b>Brake System Basics</b></p>
<p class="copy">The workings of the brake system may, at first glance, seem
obvious: we push on the brake pedal, which clamps the pads onto
the rotor, which stops the car, right? But think further: a
2400-pound vehicle in motion possesses a great amount of kinetic
energy (the energy of motion.) And the laws of physics dictate
that energy cannot be created or destroyed. So what happens to
all of the kinetic energy from a moving vehicle when the vehicle
stops?</p>
<p class="copy">Since the energy cannot be destroyed, then it must be
converted into something else. In this case, it is converted into
heat. And it is this conversion process that is the true function
of the braking system. <i>Brakes convert kinetic energy into heat
energy through friction</i>. And once all of a vehicle’s
kinetic energy has been converted, the vehicle stops – since
it has no more kinetic energy – and ends up with lots of
heat energy. This heat energy is created as a result of friction
between the brake pad and the rotor (or the shoe and the drum,)
briefly stored in the rotor (or drum,) and eventually dissipates
into the surrounding air. </p>
<p class="copy">But how does the input of force at the brake pedal (from our
foot) result in clamping force – and hence friction -
between the brake pads and the rotor? Like most of the functions
of a modern car, the operation of the "brakes" is
actually part of a larger integrated "system." And
while there are many important parts of the braking system,
suffice it to say that brake fluid is a <i>very</i> vital
component within the system. </p>
<p class="copy">In a nutshell, when we apply force to the brake pedal with our
leg, this force is increased (thanks to the lever law) based upon
the length of the brake pedal lever. This force moves through the
vacuum booster – where it gets amplified by the motor’s
vacuum – and finally gets transferred into the piston within
the master cylinder. The force against the piston in the master
cylinder pushes the piston into brake fluid. The fluid is then
forced through the brake pipes toward the brake components at the
corners of the car. Finally, the fluid pushes against the piston
within the brake caliper - which clamps the brake pads against
the rotor.</p>
<p class="copy">Clearly, the fluid is vital – since we depend upon the
liquid properties of the fluid to transfer force through the
system into the brakes at the wheels. In theory, since a liquid
cannot be compressed, we can count on the hydraulic actuation to
result in a linear transfer of forces. (In other words, we do not
expect liquid to compress. If it did compress, then we would
"waste" energy compressing the fluid instead of using
the energy to create movement at the brake corners.)</p>
<p class="copy">In summary, the role of the brake fluid within the braking
system is to transfer the force from the master cylinder to the
corners of the car. And a vital characteristic of brake fluid
that allows it to perform its task properly is its ability to
maintain a liquid state and resist compression.</p>
<p class="copyHeading"><b>Why Bleed the Brakes?</b></p>
<p class="copy">The term "bleeding the brakes" refers to the process
in which a small valve is opened at the caliper (or drum) to
allow controlled amounts of brake fluid to escape the system.
(When you think about it, "bleeding" may appear to be a
somewhat graphic term, but it aptly describes the release a vital
fluid.)</p>
<table border="0" cellpadding="4">
<tr>
<td><font color="#FF0000" size="2">*Note: technically,
"air" only enters the lines if there is a
compromise of the system’s sealing (as when flex
lines are removed or replaced.) When fluid boils, it will
instead create "fluid vapor." Vapor will create
an equivalent efficiency loss. But we use the term
"air" here for simplicity.</font></td>
<td>We bleed the brakes to release air<font color="#FF0000">*</font> that sometimes becomes trapped
within the lines. When air becomes present within the
lines, it creates inefficiencies within the system
because, unlike liquid, air can be compressed. So when
enough air fills the lines, input at the pedal merely
causes the air to compress instead of creating movement
at the brake corners. In other words, when air is present
within the system, the efficiency and effectiveness of
the braking system is reduced. Usually, a small amount of
air within the brake system will contribute to a
"mushy" or "soft" pedal (since less
energy is required to compress the air than is required
to move fluid throughout the brake lines.) If enough air
enters the brake system, it can result in complete brake
failure.</td>
</tr>
</table>
<p class="copy">So how does air enter the lines in the first place? Sometimes,
it can be the result of a service procedure or an upgrade –
such as replacing the stock flex lines with stainless steel
braided lines. But often it is the result of high temperatures
that cause brake fluid components<font color="#FF0000"> </font>to
boil, thus releasing gasses from the boiling fluid into the brake
pipes.</p>
<p class="copyHeading">Brake Fluid Selection</p>
<p class="copy">This leads one to contemplate the type of liquid that is used
as brake fluid. In theory, even simple water would work –
since, being a liquid, water cannot be compressed. However, it is
important to remember that the fundamental function of the
braking system is to convert kinetic energy into heat energy
through friction. And the reality of this process is that certain
parts of the braking system will be exposed to very high
temperatures. In fact, testing on the scR showroom stock racecar
has shown that rotor temperatures during a race will become as
high as 1100 degrees Fahrenheit.<font color="#FF0000">*</font>
Since the boiling point of water is 212 degrees Fahrenheit, it is
easy to see that water within the brake system could boil easily
– and therefore release gases into the brake pipes –
which will reduce the efficiency of the system. (Water would also
present a big problem in cold weather if it froze to ice!)</p>
<table border="0" cellpadding="4">
<tr>
<td>The "obvious" solution to this problem is
to utilize a fluid that is less sensitive to temperature
extremes. Hence the development of "brake
fluid." However, there unfortunately is no such
thing as a "perfect" brake fluid. And like most
things in the world, the addition of certain beneficial
characteristics usually brings tradeoffs in other areas.
In the case of brake fluid, we generally must balance the
fluid’s sensitivity to temperature against its cost
and its impact upon other components within the system.</td>
<td><font color="#FF0000" size="2">*Note: Even though the
rotor gets very hot, the brake fluid will never see such
high temperatures – since the heat must be passed
through the brake pad, caliper, piston, and other
components. Most of the heat will dissipate along this
route before reaching the brake fluid. Previous testing
has indicated that a rotor temp between 800-900 degrees
Fahrenheit can result in a fluid temperature closer to
300 degrees Fahrenheit – still enough to boil water!</font></td>
</tr>
</table>
<p class="copy">Stated more bluntly, it is possible to reduce a fluid’s
sensitivity to temperature by varying the ingredients of the
fluid. However, certain combinations of ingredients can
significantly increase the cost of the fluid and may react with
OEM materials to damage seals and induce corrosion throughout the
braking system.</p>
<p class="copy">The chemical composition and minimum performance requirements of the fluid are generally
indicated through a rating such as "
OT3," DOT4,"or "
OT5." The DOT-rating itself is assigned after aseries of government tests. However, this rating is NOT intended
to indicate boiling points, even though higher DOT ratings
generally do correspond with higher boiling points. Perhaps more
importantly, the DOT rating <i>does</i> indicate the base
compound of the brake fluid - which allows manufacturers to
specify fluid types which are less likely to react negatively to
known materials used within a particular braking system.</p>
<p class="copy">The greatest irony about brake fluid, however, is the fact
that the chemical compositions that tend to be less sensitive to
temperature extremes also tend to attract and absorb water! So
even though the fluid <i>itself </i>is unlikely to boil (most
glycol-based DOT3 fluids have a "dry boiling point"
around 400 degrees Fahrenheit,) the water that it absorbs over
time tends to boil easily (at 212 degrees Fahrenheit.) It is this
characteristic of absorbing moisture that leads to the measure
known as the "wet boiling point." The wet boiling point
is the equilibrium boiling point of the fluid after it has
absorbed moisture under specified conditions. Because brake fluid
will absorb moisture through the brake system’s hoses and
reservoir, evaluation of the wet boiling point is employed to
test the performance of <i>used</i> brake fluid and the
degradation in it’s performance. (And it is why we still
need to bleed the brakes frequently on the racecars, even though
we use AP600 racing fluid that costs $18 per bottle!) The lesson:
do NOT expect to avoid bleeding your brakes just because you
bought expensive brake fluid.</p>
<p class="copy">As one might guess, "racing" fluids will use
relatively "aggressive" chemical compositions which
will tend to have higher wet boiling points and higher costs,
while the average street fluids will use more conservative compositions which will have lower wet
boiling points and lower costs. In some cases – such as a
purpose-built racecar – the tradeoffs of using the expensive
racing fluid is outweighed by the competitive advantages. But for
the average driver – whose driving style is less likely to
induce very high brake temps – the costs of the fluids and
potential wear-and-tear factors upon system components may
justify the use of a more conservative fluid with a lower wet
boiling point.</p>
<p class="copyHeading">The Proper Bleeding Procedure</p>
<p class="copy"><b>Supplies Preparation</b></p>
<p class="copy">You will need the following tools:</p>
<ul>
<li>10mm box-end wrench (8mm for rear drum brake units.) An
offset head design works best.</li>
<li>Extra brake fluid<font color="#FF0000"> </font>(1 pint if
you are just bleeding, 3 if you are completely
replacing).</li>
<li>14-inch long section of 3/16 in. ID clear plastic tubing.</li>
<li>Disposable bottle for waste fluid.</li>
<li>One can of brake cleaner.</li>
<li>One assistant (to pump the brake pedal.)</li>
</ul>
<p><b>Vehicle Preparation and Support</b></p>
<ol>
<li>Loosen the lug nuts of the road wheels using a 19mm
socket and place the entire vehicle on jackstands. Be
sure that the car is firmly supported before going <b><i>ANY</i></b>
further with this installation! </li>
<li>Remove all road wheels.</li>
<li>Install one lug nut backward at each corner and tighten
the nut against the rotor surface (to limit flex that may
distort pedal feel.)</li>
<li>Open the hood and check the level of the brake fluid
reservoir. Add fluid as necessary to ensure that the
level is above the seam of the reservoir. Do not let the
reservoir become empty during the bleeding process.</li>
</ol>
<p class="copy"><b>Bleeding Process</b></p>
<ol>
<li>Begin at the corner furthest from the driver and proceed
in order toward the driver. (Right rear, left rear, right
front, left front.)</li>
<li>Locate the bleeder screw at the rear of the caliper body
(or drum brake wheel cylinder.) Remove the rubber cap
from the bleeder screw.</li>
<li>Place the box-end wrench over the bleeder screw (10mm for
discs, 8mm for drums.) An offset wrench works best –
since it allows the most room for movement. (If you do
not have an offset wrench, avoid pushing the wrench head
to the bottom of the bleeder screw – since the
wrench may interfere with other parts during movement.
Allow a standard wrench to sit near the top of the
bleeder screw contact point.)</li>
<li>Place one end of the plastic hose over the nipple of the
bleeder screw.</li>
<li>Place the other end of the hose into the disposable
bottle.</li>
<li>Place the bottle for waste fluid on top of the caliper
body or drum unit. Hold the bottle with one hand and
grasp the wrench with the other hand.</li>
<li>Instruct the assistant to "apply." The
assistant should pump the brake pedal three times, hold
the pedal down firmly, and respond with
"applied." Instruct the assistant not to
release the brakes until told to do so.</li>
<li>Loosen the bleeder screw with a brief ¼ turn to release
fluid into the waste line. The screw only needs to be
open for one second or less. (The brake pedal will
"fall" to the floor as the bleeder screw is
opened. Instruct the assistant in advance not to release
the brakes until instructed to do so.) </li>
<li>Close the bleeder screw. </li>
<li>Instruct the assistant to "release" the brakes.
Note: do NOT release the brake pedal while the bleeder
screw is open, as this will suck air into the system! </li>
<li>The assistant should respond with "released."</li>
<li>Inspect the fluid within the waste line for air bubbles.</li>
<li>Continue the bleeding process (steps 11 through 16) until
air bubbles are no longer present. Be sure to check the
brake fluid level in the reservoir after bleeding each
wheel! Add fluid as necessary to keep the level above the
seam line.</li>
<li>Move systematically toward the driver – right rear,
left rear, right front, left front - repeating the
bleeding process at each corner. </li>
<li>When all four corners have been bled, spray the bleeder
screw (and any other parts that were moistened with
spilled or dripped brake fluid) with brake cleaner and
wipe dry with a clean rag. (Leaving the area clean and
dry will make it easier to spot leaks through visual
inspection later!) Try to avoid spraying the brake
cleaner DIRECTLY on any parts made of rubber or plastic,
as the cleaner can make these parts brittle after
repeated exposure. </li>
<li>Test the brake pedal for a firm feel. (Bleeding the
brakes will not necessarily cure a "soft" or
"mushy" pedal – since pad taper and
compliance elsewhere within the system can contribute to
a soft pedal. But the pedal should not be any worse than
it was prior to the bleeding procedure!)</li>
<li>Be sure to inspect the bleeder screws and other fittings
for signs of leakage. Correct as necessary.</li>
<li>Properly dispose of the used waste fluid as you would
dispose of used motor oil. <font color="#FF0000">Important:
used brake fluid should NEVER be poured back into the
master cylinder reservoir! </font></li>
</ol>
<p><b>Vehicle Wrap-Up and Road Test</b></p>
<ol>
<li>Re-install all four road wheels. </li>
<li>Raise the entire vehicle and remove jackstands. Torque
the lug nuts to 140 Nm (103 ft-lb) using a 19mm socket.
Re-install any hubcaps or wheel covers also using a 19mm
socket.</li>
<li>With the vehicle on level ground and with the car NOT
running, apply and release the brake pedal several times
until all clearances are taken up in the system.</li>
<li>Road test the vehicle to confirm proper function of the
brakes. <b><i>USE CAUTION THE FIRST TIME YOU DRIVE YOUR
CAR AFTER MODIFICATION TO ENSURE THE PROPER FUNCTION OF
ALL VEHICLE SYSTEMS!</i></b></li>
</ol>[/html:2pp5pd7r]