Cooling Systems Flashcards
A water pump is what type of pump
Non positive displacement
What is thermal efficiency
The measure of an engines ability to convert energy content of fuel into mechanical force
What do the best heavy duty diesel engines operate at (thermal efficiency)
45% thermal efficiency
What is heat rejection
The release of heat to cooling system
What are 2 important reasons cooling systems are under pressure?
Maintain pressure higher than atmospheric pressure, 14.7. Pumps operate less efficiently without pressure
Increases boil point. Every 1 psi boiling point increases by 3°F
Wjat is a condition unique to diesel engines?
Cavitation of cylinder Walls and liners
What is the most significant additive that prevents cavitation?
Nitrate
What does DCA stand for
Diesel coolant additive
What does SCA stand for
Supplemental coolant additive
What does a heat exchanger do
Transfers heat from coolant to the atmosphere
Coolant PH is?
Measured on a scale from 0-14
7 is neutral
Below 7 is acidic
Above 7 is alkaline
Coolant PH should be between 8.5 and 10.5
How many ounces of ethylene glycol will cause kidney failure?
4 ounces
What are two types of rads
Down flow
Cross flow
At what temperature does the thermostat open?
180°F
What do calibrated pressure valves do
Increases pressure of system and Raises boiling point
