202D - Cooling Flashcards
What are the two glycol based antifreezes used in modern vehicles?
- Ethylene glycol
- Propylene glycol
202da pg. 11
Is ethylene glycol or propylene glycol more toxic?
Ethylene Glycol
- More toxic
Propylene Glycol
- Exact degree of toxicity is unknown
202da pg. 11
At what temperature range will a 180F thermostat begin to open?
178F - 182F
Begins to open within 1C (2F) of the indicated (plus or minus 1C or 2F)
202db pg. 12
What percentage of combustion heat is removed by the cooling system?
Approximately 33%
202da pg. 2
A 1psi increase in pressure will raise the boiling point of water how much?
3F
1 psi increase = 3F increase boiling point
6.92kPa increase = 1.66C increase boiling point
202da pg.5
What is used to increase the efficiency at which an engine fan moves air past the radiator?
Fan shroud
202da pg. 23
What type are the majority of engine water pumps?
Non-positive displacement centrifugal
202da pg. 30
What two things are engine fan clutches designed to reduce?
- Horsepower loss
- Fuel consumption
202da pg.24
When is coolant drawn into the engine cooling system from the recovery tank?
When the engine cools down
202da pg.19
A water manometer can be used to check what two areas of a running engine?
- Inlet restriction: After air cleaner & before turbo
- Blow-by
What two valves are located in a radiator cap?
- Pressure valve
- Vacuum valve
202db pg. 7
What is a full blocking thermostat?
Thermostat that allows no coolant to flow through to the radiator when the coolant is cold. Allows for faster engine warm-up time.
202da pg. 20
What is a partial blocking thermostat?
Thermostat that allows up to 10% of the cold coolant to flow through to the radiator.
202da pg. 20
What are SCA’s?
Supplemental Coolant Additives
Corrosion inhibitors that can be added in after a coolant analysis to increase protection or replenish the original inhibitors.
202da pg. 13
