ASE A5 - key notes Flashcards
the metering valve
holds off pressure on the front brakes ever so slightly to allow the rear drums brakes to engage first
the pressure differential valve
is the device that alerts you if you have a leak in one of the brakes circuits
brake proportioning valve
are the parts of a vehicle’s brake system that limit the amount of pressure reaching the rear brakes, which helps to prevent rear wheel lock up.
master cylinder
can cause LOW brake pedal/ fades pedal to the floorboard when leaking cup seals.
low intake manifold/vacuum/clogged check valve
can all cause HARD brake pedal
sticking caliper piston seal
will make one brake rotor hotter than the others
residual check valve
used on DRUMS system to keep 5-12 psi on wheel cylinder cup seals/ can also cause SPONGY pedal
break accumulators
are found on Integral & NON- integral ABS/ stores pressures
double- walled STEEL tubing
always used to repair damaged section of Brake line
Brake Drag
can be caused by Weak return spring/ Twisted brake hose
dial indicator
check Lateral runout (WARPAGE) of rotor
outside micrometer
check Thickness of rotor
if you open the Bleeder and there isn’t fluid passing to the brake caliper- there is ________ on the hose
RESTRICTION
Short Push Rod
will result in excessive pedal travel
Air in the Hydraulic system
will cause SPONGY brake pedal
Free play brake pedal
pressure build up/ dragging brakes
Defective one-way check valve in Booster vacuum hose
will cause brake fluid into engine
Seized Caliper Piston
will NOT cause LOW brake pedal
Caliper- integrated parking brakes (EPB)
Does NOT use Hand-operated lever.
Excessive pedal travel
can be caused by Incorrect adjustment on Master Cylinder pushrod
Dot 3 & 4 Brake Fluid
is Hygroscopic, which means they absorb moisture.
Dot 5 Brake Fluid
is Silicon, High boiling point/ does not attract water
4 different methods for Bleeding Brakes
manual, pressure, vacuum, and surge
SINGLE channel ABS system
installed on rear wheels only
FOUR channel ABS sensors
will have 4-wheel speed sensors, one for each wheel
Silicone based brake grease
Is the type of Lubricant you use on brakes
Wheel torque that is TOO Tight
could cause warp on brake rotors/ pedal pulsation
Hydro-Boost
Power Steering issue
Worn Brake Pedal Linings
causes NOISE not pulsation
ABS LIGHT
wheel speed sensor issue
Red Brake LIGHT
hydraulic problem such as low fluid or LOSS of pressure
Brake pedal fade
can also be caused by Brake drum beyond its machined limit
Vacuum supply test
Involves inspecting the vacuum supply hose for kinks & checking the level of vacuum supplied by the engine or vacuum pump
2 main types of flares for brake lines
Bubble & Double Flare