13940017 Brake-Chek Digital Pocket Refractometer DOT3 Celsius

Features

• Quick, automatic digital measurements
• Economical to operate, 10,000+ measurements on two "AAA" batteries
• World's smallest handheld brake fluid tester
• Test brake fluid without boiling
• Only small sample of brake fluid needed for results
• No messy cleanup
• Measure in degrees Fahrenheit both DOT3 and DOT4
• Measure in degrees Celsius both DOT3 and DOT4

With the simple push of a button, The Digital Brake-Chek, the world's smallest handheld tester, will quickly and accurately provide you with critical brake fluid boiling point date. 

When water content in brake fluid increases...

1. The boiling point decreases
Fluid with a reduced boiling point can create a vapor by boiling in the wheel cylinder. Normally this could happen under adverse conditions such as braking down a long steep grade or with stuck brake pads. Under these conditions rotor temperatures can climb high enough to boil brake fluid with high water content. Stepping on the brake pedal will now only compress the vapor instead of applying force to the pad. The result is sudden brake failure. DOT3 Fluid with no moisture content boils at greater than 401°F (205°C) as specified by DOT Standard 116.  The fluid in a 3 to 4 year old car with 3 to 4% moisture content could boil at less than 300°F (149°C).

The dry boiling points for the brake fluid classes are:
Fluid TypeDry Boil Point
DOT3   401°F/205°C
DOT4   446°F/230°C

2.  The viscosity increases
Brake fluid must flow freely to be effective. In extremely cold weather brake fluid with high water content is very viscous, causing slow pedal response and requiring more effort. 

3.  Corrosion problems can occur
Water in brake fluid can contribute to the corrosion of parts such as the steel pistons and ABS modulators. 

Specifications