Document pBe76eKDkNMDGGX1MaRy088jj
LESSON ONE-MODULE 2 BRAKE FLUID
BRAKE SYSTEM SERVICE
DOT3
BRAKE FLUID BOILING POINTS MINUMUM FEDERAL SAFETY STATNDARDS
*F 'C
DRY
WET
DRY
401 284
205
WET 140
FORD DOT3 550
EXCEEDS REQUIREMENTS
228 EXCEEDS REQUIREMENTS
NOTE: A NEWLY OPENED CAN EXCEEDS ALL MINIMUM REQUIREMENTS
BSR048-A
Brake Fluid Boiling Points
DOT 3 brake fluid is dear when originally installed in a vehicle. The color of brake fluid in a brake system over a period of time may vary for a number of reasons. Sometimes the fluid in a brake master cylinder may show significantly different shades of color between the two halves of the reservoir. Fluid color may appear to vary between cast steel and die cast aluminum reservoirs. Some of the reasons for the apparent difference in color in a system are listed below:
Fluid discoloration can occur due to heat and/or aging.
Difference in color between the two halves of the master cylinder can occur due to the different operating temperatures or different rates of normal oxidation between the different hydraulic circuits.
Fluid color may vary when different brands of brake fluid are used in topping off the master cylinder during normal service.
Fluid discoloration can occur through dissolution of color dye used in the manufacture of the springs used in the master cylinder.
NOTE: Brake fluid contaminated with a hydrocarbon/mineral based fluid (transmission fluid, power steering fluid) can be detected by an obvious swelling of the master cylinder cap gasket. If a swollen cap gasket is present, all rubber components in the brake system must be replaced (these components are listed later in this lesson).
CAUTION: Contamination of the brake hydraulic system requires the replacement of all rubber / ' ' components of the system. These include:
Fluid control valve(s)
Brake caliper seals
Rubber brake hoses
Brake wheel cylinder seals
Pressure control valves
Master cylinder primary and secondary piston assemblies
Reservoir Grommets
Cap assemblies
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September, 2005
Brake System Diagnosis and Repair