Need to find out more about car brakes? What's a brake caliper? What does brake fluid do? Are squealing brakes always a bad sign? How do a install a auto brake conversion kit? This powerpoint is a great intro into everything that has to do with car brakes.
1. Car How To Brakes
Welcome to Brakes 101
source: http://www.buyautoparts.com/howto/repair-brake-system.htm
2. What is a Brake Caliper?
• The brake process is very straight forward - friction between a rotating component (the drum of disc) and
a stationary component (the brake shoe or pad) causes the drum or disk to slow down.
• The size of the pad itself and the clamping force that is used to generate the friction is ultimately a
function of the design of the caliper, which houses the pistons used to compress the pads onto the disc.
Many road car calipers use a single sided design on sliding pins. This means the piston or pistons are only
on one side of the caliper, usually the inside and as they extend they press the pad against the disc. The
reaction causes the whole caliper to slide on pins and pull the opposite pad onto the disc as well.
• A better option is to have at least a pair of pistons, one on each side of the caliper forcing the pads onto
the disc evenly. However, this inevitably increases the thickness of the caliper, which can cause problems
with the space behind the wheel.
• The number and size of the pistons in the caliper will be chosen the match the car. For example, a heavy
car may have four-piston calipers to allow a bigger pad to be used to generate more braking force.
• As a rough rule of thumb a four-piston caliper can handle a 131mm long pad while a six-piston version will
allow 152mm long pads. Because of the amount of friction generated is directly related to the size of the
pad contact area and the force clamping it, a bigger pad will give stringer brakes, with all other forces
being equal.
• Another benefit of multiple-piston calipers is to combat pad tapering. When braking is taking place, the
surface of the pad gets hot and it it gets too hot the material can begin to melt as the metallic elements
become molten. As it does so, it begins to flow in the same direction as the rotation of the disc. This in
turn leads to the pad becoming wedge shaped. So a smaller piston at the leading edge of the pad and a
larger one at the trailing edge will provide more force to the area when the material will build up and help
to keep the pad flat against the disc.
source: http://www.buyautoparts.com/howto/brake-calipers.htm
3. What is a
Brake
Caliper?
cont.
source: http://www.buyautoparts.com/howto/brake-calipers.htm
4. What is a Brake Disc?
• The disc brake slows or stops the rotation of a wheel. A brake disc is usually made
of cast iron or ceramic and is connected to the wheel. To stop the wheel, friction
material in the form of brake pads (mounted in a caliper) is forced hydraulically
against both sides of the disc. Friction causes the disc and attached wheel to slow
or stop.
• Disc brakes don't suffer the seizing (as drum brakes do) for several reasons. Firstly,
they work by forcing a pair of pads against the outside of a spinning disc. Because,
certainly on the front, they don't need to produce and hand brake effect, there is
no mechanical adjustment and wear in the pads is compensated by slightly greater
piston travel.
• Further benefit of disc brakes is that the friction generation process takes place in
open air, so there is far better cooling of the whole operator. To improve this even
further, for hard braking applications (such as track days or motorsports) additional
air can be ducted onto the brakes to cool them even more.
• Discs will also usually be ventilated, with a series of vanes allowing air into the
middle section of the disc. This increases the surface area that the cooling air
comes into contact with and removing yet more heat for better efficiency.
source: http://www.buyautoparts.com/howto/brake-disc.htm
5. What is a
Brake Disc?
cont.
source: http://www.buyautoparts.com/howto/brake-disc.htm
6. What is Brake Fluid?
• Brake fluid is possibly the most crucial aspect of the whole braking system, since it is what
transfers your stomp on the pedal into clamping force at the caliper.
• It is also the least considered aspect. With brake fade the remedy is to simply stop using
them and let them cool down. However, if you don't and keep trying to stop, then you would
start to transfer significant amounts of heat into the fluid, which is after all filling the calipers.
• If enough heat goes into the fluid, then it can boil, which is a very bad thing. Fluids are
incompressible but vapor is not. So when the fluid boils, it turns into vapor and as you hit the
brakes, just the vapor is compressed rather than forcing the fluid into the calipers. At that
point the pedal will go to the floor and nothing will happen.
• If you are planning on using your brakes in an extreme manner such as racing then an
upgrade to the fluid is recommended.
• The three main types of brake fluid now available are DOT3, DOT4 and DOT5. DOT3 and DOT4
are glycol-based fluids and DOT5 is silicon-based. The main difference is that DOT3 and DOT4
absorb water while DOT5 does not.
• AAs a DOT3 and DOT 4 brake fluid absorbs water, its boiling point decreases. It can absorb
water from the air, which is why you should avoid opening a cars brake system reservoir. For
the same reason, containers of brake fluid should be kept tightly sealed.
• DOT5 fluid does not absorb water. This means the boiling point will remain relatively stable,
but it also means that any water in the system will form pure water pockets, which could
cause brake corrosion.
• AAdditionally, none of the different types of brake fluid should be mixed. They can react
badly with each other and corrode the brake system.
source: http://www.buyautoparts.com/howto/brake-fluid.htm
7. What is
Brake Fluid?
cont.
source:
http://www.buyautoparts.com/h
owto/brake-fluid.htm
9. When are Squealing Brakes a Problem?
• Sometimes brake squeals are an indication that maintenance is required. Some
common conditions that cause brake noise are:
• Heat cracked or worn "un-true" rotors Rough finish on resurfaced rotors Loose
fitting brake pads in the caliper Lack of silicone compound on back of brake pad
Missing springs or anti-rattle clips that should be on the caliper or pad Improper
tightening sequence of lug nuts or caliper hardware.
• Most GM cars are equipped with a small thin piece of metal attached to the brake
pad to act as a warning indicator when the pad material is getting low and the
brake pads should be replaced. This inexpensive warning device can be deceiving
though, because this warning noise is present when the brakes are not depressed.
When the brakes are applied, the warning noise goes away because the indicator
has now been forced against the brake rotor and is not able to vibrate which
causes this whistling noise.
• If you hear brake noises other than a squeal, it could mean your brake pads are
worn out and need to be replaced. If your brake pedal feels different than normal
or if you've noticed any change in the way your vehicle brakes (pulls to one side
when braking or requires more pressure on the brake pedal), have the brake
system inspected at once.
source: http://www.buyautoparts.com/howto/when-are-squealing-brakes-a-problem.htm
10. When are Squeals NOT a Problem?
• Some brands of semi-metallic pads are inherently noisier than others
because of the ingredients used in the manufacture of the friction
material.
• Think of it this way, the longer life pads or pads that claim to have more
stopping power usually contain more metallic material. Yes, they will last
longer and could enhance braking but the chance of causing a squeal
noise is very high.
• The squealing noise that might be caused from use of these pads does not
affect braking performance and does not indicate a brake problem.
• Brake squeal is caused by vibration between the brake pads, rotors, and
calipers. Having the brake rotors refinished or trued (machining a small
layer of the metal away from the brake rotor to make it smooth and "true"
again) and a thin layer of a silicone compound placed on the back of the
brake pads are a great way to reduce the squeal if the semi-metalic pads
are the culprit of the noise and not due to a worn out brake pad.
source: http://www.buyautoparts.com/howto/when-are-squealing-brakes-not-a-problem.htm
11. What Should I Do About Squealing Brakes?
• First of all, noisy brakes should always be inspected to make sure
there isn't a problem with the braking system. If the pads have
worn down to the point where metal-to-metal contact is occurring,
your vehicle may not be able to stop safely, and you may damage
the brake rotors or drums to the point where they have to be
replaced. Sometimes a few harder-than-normal stops can "de-
glaze" the brake pads and help reduce the squealing noise for a
while.
• There are many aftermarket brake pads that claim to be "quiet" or
have been "designed" for import and front wheel drive vehicles that
you can choose from. Personally, I have had the best luck replacing
the brake pads on small vehicles like Honda and Toyota with original
equipment pads from the dealership rather than using aftermarket
brands. It is usually more expensive to purchase these pads from
the dealership, but the quality is much better.
source: http://www.buyautoparts.com/howto/what-can-be-done-about-squealing-brakes.htm
12. Now for something a little more
difficult
Disc Brake
Conversion Kits
13. How To Install Disc Brake Conversion Kit?
• The basic process for a disc brake conversion is very
straight forward but there are always small steps that
can be missed. The best way to avoid these small steps
is to have a step by step installation guide and a
mechanic who knows the process.
• This is following slides are not an official install or
instructional guide and BuyAutoParts.com is not
responsible for any damage or injury that can occur
during these procedures. It is always recommended
that all parts be installed by a licensed mechanic.
source: http://www.buyautoparts.com/howto/71-20010-install-instructions.htm
14. Parts
Commonly
Included in
a Kit
source:
http://www.buyautopar
ts.com/howto/71-
20010-install-
instructions.htm
23. Disc Brake Conversion Videos
• These series of videos documenting the installation of a disk brake
conversion system for a drum brake vehicle.
– First remove the wheel and old drum brake assembly. To remove the
axle a slide hammer will be needed to complete the job. Be sure that
the brake line is loose from the brake drum and detach the line from
the brake system.
– Now clean up the area to be sure there is no debris in the system
before the install.
– Install the spacer and reinstall the axle shaft into the rear end.
– Next attach the caliper mounting bracket to the axle assembly on the
OEM factory mounting holes.
• To Watch the video click this link,
http://www.buyautoparts.com/howto/install_disk_brake_conversio
n_kit_part_1.asp
24. Disc Brake Conversion Videos - 2
• In this second installment of the disk brake conversion
install videos you will see how to attach the mounting
brackets for the brake calipers.
– Next you will learn how to attach the brake rotor and
caliper on to the correct location.
– Installing a parking brake cable and adjusting the piston
internally to make correct brake pressure is also covered.
– When doing this install be sure that your brake master
cylinder to keep up with the new demand.
• To Watch the video click this link,
http://www.buyautoparts.com/howto/install_disk_bra
ke_conversion_kit_part_2.asp
25. Car How To Brakes
The End
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Thanks
source: http://www.buyautoparts.com/howto/repair-brake-system.htm