Cooling & Accessory Drive Systems Flashcards
How long does a serpentine belt last?
100k / 4 years
How do you measure belt tension?
Press belt midway by the longest span between 2 pulleys, if belt moves more then 1.25cm per 30cm, it should be adjusted
What is a V-belt?
Belt only rides on the inside of the belt, and makes contact on the belt sides
What is a V-Ribbed?
Belt rides and flexes both ways
What is the operating temperature of an engine?
just below 100 degrees
How much is a Rad cap typically rated for?
14PSI to 21PSI
What is the purpose of a Block Heater?
Heats up the coolant to warm up the combustion chamber allowing the liquid fuel to vaporize easier and not flood
How can a Voltmeter be used to check the condition of the coolant?
Can be checked for electrolysis. Attach negative to ground and place the positive lead into the coolant.
Readings of 0 to 0.3 volts are normal for a cast-iron engines and about half for aluminum engine
What is the most common cause for coolant hose failure?
Electrochemical degradation
If a thermostat has a locating pin, what orientation does it go?
Always up
How often should IAT coolants be flushed?
2 years
How often should DexCool or OAT coolants be flushed?
5 years
When doing a coolant flush, how much coolant should be added to the machine?
First determine the vehicles coolant capacity, then determine your coolant/water mixture (i.e. 60-40). Multiple the capacity by 0.01 times the coolant percentage (i.e. 0.6)
How much does water boiling point increase for every PSI increase?
1.6 degrees Celsius for every 1PSI
When does a thermostat begin opening and when is it fully open?
begins opening at 1.6 degrees Celsius above/below operating temp, and is fully open 11 degrees Celsius above that
What is the minimum percentage of coolant required in any climate?
44%
What is Cavitation?
Erosion or pitting caused by the formation & rapid collapse of vapor bubbles formed in fast-moving or boiling coolant
What are the 5 types of coolants?
Ethylene Glycol, Propylene Glycol, Phosphate-free, Organic Acid Technology (OAT) and Hybrid-OAT
Which coolant type is least abrasive to waterpumps?
Hybrid Organic Acid Technology
What coolant type is often referred to as DexCool?
Organic Acid Technology
What coolant type is most poisonous and typically green in color?
Ethylene Glycol
What coolant tester uses a pickup hose, reservoir and squeeze ball to test for coolants freezing point?
Hydrometer
How much should pulleys be in alignment of one another?
1.6mm per 30cm (1ft.)
What is the Wax in a Thermostat made up of?
Copper, Graphite and/or Aluminum
What is the freezing and boiling point for a 50/50 coolant mixture?
Freezes at -37 degrees Celsius and boils at 107 degrees Celsius
