MARCH-2004 Oil Pumps 1. What are we looking at in this picture? 2. What type of oil pump is this? 3. What is the maximum generic tolerance measurement between the gears? 1. Oil Pump 2. Gear ”
MARCH-2004 Oil Pumps 1. What are we looking at in this picture? 2. What type of oil pump is this? 3. What type of displacement is this pump? 1. Oil Pump 2. Rotor 3. Positive
MARCH-2004 Cooling Systems 1. What are 2 types of cooling systems? 2. What are the 9 items listed in the diagram? 1. Air - Liquid
MARCH-2004 Cooling Systems One at a time, identify 1 component & a brief description of its purpose.
MARCH-2004Coolant 1. What is the ideal coolant mixture ratio? 2. What is the boiling point of water? 3. What is the boiling point of a 67/33 mix? 1. 67/ º F º
MARCH-2004 Radiator Caps 1. What is the purpose of a radiator cap? 2. Every PSI of pressure = how much of an increase in the boiling point? 1. Increase boiling point – Refill reservoir ºC or 3.2ºF
MARCH-2004 Radiator Caps 1. How many types of radiator caps are there? 2. What is the average pressure rating of today’s caps? 3. How do we test radiator caps? 1. 3 – constant/vent/closed PSI 3. Visual/Pressure test
MARCH-2004 Radiator Hoses 1. What is the purpose of radiator hoses? 2. What element is used to make the hoses black? 3. Which hose is subject to the roughest service life? 1. Contain/Transport coolant 2. Carbon 3. Upper radiator hose
MARCH-2004 Hose Clamps 1. How many types of hose clamps may we see? 2. What are the names of these hose clamps? 1. 5 Types 2. Screw Tower – Spring – Rolled Edge – Worm Gear – Twin wire
MARCH-2004Thermostats 1. What are 2 functions of a thermostat? 2. When must a thermostat begin to open? 3. When must the thermostat be “fully” open? 1. Control temperature & Flow 2. 3ºF above or below rating 3. 20ºF above “start to open”.
MARCH-2004 Fans & Fan Clutches 1. What 2 types of fans are shown? 2. Identify 2 types of downsides to these types of fans. 3. Why are fan shrouds used? 1. Flex - Clutch 2. Rob horsepower - Noisy 3. Efficiency –Engine placement
MARCH-2004 Electric Cooling Fans 1. Why are electric fans used? 2. What components are needed to make this system work? 3. Do these fans run while driving? 1. Efficiency - Control 2. Sensor-Switches-Relays-Wiring-Fuse 3. Typically they shut down at 40km/hr & up.
MARCH-2004 Service & Repair Oil pressure sending units External leaks Corrosion Belts Component failure Fluid breakdown – lack of maintenance Adjustments Electrolysis Common Failures
MARCH-2004Scenarios Customer complained of no heat. A vehicle was “taking coolant”. Gauge always reads lower than normal. Boils over during highway driving. Customer wants vehicle winterized. Electric fan won’t stop running. Lets try a few examples of complaints that you will see. What would you do if:
MARCH-2004 Review Questions 1. Why would coolant read 1 volt on a DVOM? 2. Why does a radiator hose show 12 volts on a DVOM 3. Where on an engine is an oil pressure test performed? 4. What would cause low oil pressure? 5. What would cause excessive oil pressure? 6. What is “viscosity”? 7. What could be the problem if a cam seal continues to leak externally after several replacements and the shaft is not scorn?