halderman ch023 lecture
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© 2011 Pearson Education, Inc.All Rights Reserved
Automotive Technology, Fourth EditionJames Halderman
LUBRICATION SYSTEM OPERATION AND
DIAGNOSIS
23
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
ObjectivesObjectives
• The student should be able to:– Prepare for ASE Engine Repair (A1)
certification test content area “D” (Lubrication and Cooling Systems Diagnosis and Repair).
– Explain hydrodynamic lubrication.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
ObjectivesObjectives
• The student should be able to:– Describe how the oil pump and engine
lubrication work. – Discuss how oil flows to the valve train
components. – Explain how to inspect an oil pump for
wear.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
INTRODUCTIONINTRODUCTION
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
IntroductionIntroduction
• Purpose of Lubrication System– Lubricating all moving parts to prevent
wear– Helping cool the engine
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
IntroductionIntroduction
• Purpose of Lubrication System– Helping seal piston rings– Cleaning and holding dirt in suspension
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
IntroductionIntroduction
• Purpose of Lubrication System– Neutralizing acids formed as the result of
combustion– Reducing friction– Preventing rust and corrosion
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
LUBRICATION LUBRICATION PRINCIPLESPRINCIPLES
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Lubrication PrinciplesLubrication Principles
• Purpose and Function– Lubrication creates oil film to separate
surfaces and support load
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-1 Oil molecules cling to metal surfaces but easily slide against each other.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Lubrication PrinciplesLubrication Principles
• Purpose and Function– Oil does not compress but may leak out
between shaft and bearing– Under some conditions, oil keeps surfaces
from seizing but some contact occurs• Condition called boundary lubrication
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Lubrication PrinciplesLubrication Principles
• Purpose and Function– Viscosity and oil clearances help prevent
boundary lubrication and wear– Boundary lubrication usually occurs under
heavy load and at low speed
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Lubrication PrinciplesLubrication Principles
• Purpose and Function– Lubrication occurs as wedge-shaped oil film
builds between object and surface
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-2 Wedge-shaped oil film developed below a moving block.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Lubrication PrinciplesLubrication Principles
• Hydrodynamic Lubrication– Wedging action of lubricant called
hydrodynamic lubrication– Depends on force applied to rate of speed
between objects and thickness of oil
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Lubrication PrinciplesLubrication Principles
• Hydrodynamic Lubrication– Thickness of oil is called viscosity– Viscosity is the ability of oil to resist flow– Prefix hydro- refers to liquids
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Lubrication PrinciplesLubrication Principles
• Hydrodynamic Lubrication– Dynamic refers to moving materials– Hydrodynamic lubrication occurs when
wedge-shaped film of oil develops between two surfaces that are moving
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-3 Wedge-shaped oil film curved around a bearing journal.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Lubrication PrinciplesLubrication Principles
• Hydrodynamic Lubrication– Engine oil pressure system feeds oil into
the lighted loaded part of bearing oil clearance
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Lubrication PrinciplesLubrication Principles
• Hydrodynamic Lubrication– Hydrodynamic lubrication takes over as
shaft rotates in bearing to produce hydrodynamic oil film
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Lubrication PrinciplesLubrication Principles
• Hydrodynamic Lubrication– Pressure between bearings and crankshaft
can exceed 1,000 PSI (6,900 kPa) due to wedging action
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
ENGINE LUBRICATIONENGINE LUBRICATIONSYSTEMSSYSTEMS
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Engine Lubrication SystemsEngine Lubrication Systems
• Purpose and Function– Primary purpose of lubrication system is to
maintain continuous oil supply to bearings
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Engine Lubrication SystemsEngine Lubrication Systems
• Purpose and Function– Oil pressure must be high enough to get oil
to bearings with force needed for proper cooling
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Engine Lubrication SystemsEngine Lubrication Systems
• Normal Oil Pressure– Normal engine oil pressure is from 10 to 60
PSI (200 to 400 kPa), or 10 PSI per 1000 engine RPM
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Engine Lubrication SystemsEngine Lubrication Systems
• Normal Oil Pressure– Higher oil pressure occurs when engine is
cold due to higher viscosity of cold oil– Lower oil pressure occurs when at normal
operating temperature
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Engine Lubrication SystemsEngine Lubrication Systems
• Normal Oil Pressure– Lower oil pressure at idle and higher
pressure at higher engine speeds because oil pumps are “positive displacement” pumps
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Engine Lubrication SystemsEngine Lubrication Systems
• Normal Oil Pressure– Oil pressure measurements show oil pump
pressure, not pressure due to hydrodynamic forces
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-4 The dash oil pressure gauge may be a good indicator of engine oil pressure. If there is any concern about the oil pressure, always use a mechanical gauge to be sure.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Engine Lubrication SystemsEngine Lubrication Systems
• Oil Temperature– Excessive high or low temperatures are
harmful to engine– Too cold and oil becomes too thick to flow
and lubricate engine parts
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Engine Lubrication SystemsEngine Lubrication Systems
• Oil Temperature– Too hot and oil becomes too thin to provide
sufficient film strength– Estimated oil temperature
• Estimated oil temperature = Outside air temperature + 120°F
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Engine Lubrication SystemsEngine Lubrication Systems
• Oil Temperature– Oil temperature should not exceed 300°F
(150°C)
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
OIL PUMPSOIL PUMPS
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Purpose and Function– Provide 3 to 6 gallons of oil per minute– Maintain pressure to force oil through
lubrication system
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Parts and Operation– In most engines with distributor, distributor
drive gear meshes with gear on camshaft
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-5 An oil pump driven by the camshaft.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Parts and Operation– Oil pump is driven from end of distributor
shaft – Distributor-driven oil pump turns pump at
one-half engine speed
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Parts and Operation– On crankshaft-drive oil pump systems, oil
pump turns at same speed as crankshaft
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– All oil pumps are positive displacement
pumps– Each rotation delivers same volume of oil– Delivers oil at higher pressure as speed of
pump increases
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– Two types of oil pumps: gear or rotor– External gear type
• Usually driven by shaft from distributor
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– External gear type
• Rotates at half crankshaft speed• Consists of two spur gears—one gear is
driven while one is idle
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– External gear type
• As gear teeth come out of mesh, they are filled by oil from pump inlet
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– External gear type
• When pump pumps, soil goes outside of each gear between gear teeth and housing
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– External gear type
• As teeth mesh, oil is forced into oil passage creating pressure
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-6 In an external gear-type oil pump, the oil flows through the pump around the outside of each gear. This is an example of a positive displacement pump, wherein everything entering the pump must leave the pump.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– Internal/external gear type
• Driven by crankshaft and operates at engine speed
• Two gears and crescent stationary element used
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-7 A typical internal/external oil pump mounted in the front cover of the engine that is driven by the crankshaft.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– Rotor type
• Driven by crankshaft• Uses lobe-shape gear meshing with inside of
lobed rotor
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– Rotor type
• Center lobed section is driven; outer section idles
• As lobes separate, oil is drawn in
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– Rotor type
• As pump rotates, oil is carried between lobes
• As lobes mesh, they force oil out from between them under pressure
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– Rotor type
• Pump maintains pressure of at least 10 PSI (70 kPa) when engine is hot and idling
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-8 The operation of a rotor-type oil pump.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– Gerotor type
• Uses inner and outer rotor• Term derived from “generated rotor”
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Types of Oil Pumps– Gerotor type
• Inner rotor has one fewer teeth than outer rotor
• Both rotors rotate
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-9 Gerotor-type oil pump driven by the crankshaft.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pressure Regulation– Maximum pressure is limited with pressure
relief valve– Relief valve sometimes called pressure
regulating valve– Relief valve limits maximum pressure by
bleeding oil to inlet side of pump
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-10 Oil pressure relief valves are spring loaded. The stronger the spring tension, the higher the oil pressure.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pressure Regulation– Relief valve spring tension determines
maximum oil pressure– Without relief valve, oil pressure increases
as engine speed increases
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pressure Regulation– Oil pump large enough to provide pressure
a low engine speeds– Oil pump small enough so it won’t cavitate
at high speed
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pressure Regulation– Cavitation occurs when pump pulls oil
faster than it can flow from pan to pickup– When pump cannot get enough oil, it pulls
air
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pressure Regulation– NOTE: Sheet metal covers over pickup
screen prevent cavitation. Oil under cover helps prevent pump from drawing air.
– Oil from pump flows through oil filter and then to moving parts
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-11 A typical engine design that uses both pressure and splash lubrication. Oil travels under pressure through the galleries (passages) to reach the top of the engine. Other parts are lubricated as the oil flows back down into the oil pan or is splashed onto parts.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Leaks
• Leaks are clearances at end points of lubrication system
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Leaks
• These clearances are necessary for proper engine operation
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Leaks
• As parts wear, leaks become greater and oil pressure drops
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Oil pump capacity
• Oil pump must supply extra oil for leaks
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Oil pump capacity
• Capacity of oil pump determined by size, rotating speed, condition
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Oil pump capacity
• If leaks are greater than pump capacity, oil pressure is low
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Oil pump capacity
• Higher engine speed increases capacity of pump to force oil out of leaks
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Oil pump capacity
• NOTE: Clogged oil pump pickup screen can cause lower oil pressure.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Viscosity of engine oil
• Viscosity affects pump capacity and leakage
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Viscosity of engine oil
• Oil with low viscosity slips past edges of pump and flows freely from leaks
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Viscosity of engine oil
• Hot oil has low viscosity so hot engine has lower oil pressure
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Viscosity of engine oil
• Cold oil is more viscous resulting in higher pressures
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Factors Affecting Oil Pressure– Viscosity of engine oil
• Higher viscosity oil raises oil pressure to regulating setting of relief valve at a lower engine speed
?
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Cover is removed to check condition of oil
pump– Visual inspection
• Inspect gears and housing for scoring
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Visual inspection
• Replace pump if heavy scoring apparent
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-12 (a) A visual inspection indicated that this pump cover was worn.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-12 (b) An embedded particle of something was found on one of the gears, making this pump worthless except for scrap metal.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Measurements
• If light scoring, measure pump clearances• Feeler gauge often used for measurements
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Measurements
• Gauging plastic used to measure space between side of gears and cover
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Measurements
• Replace if excessive clearance or scoring is found
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– NOTE: Oil pump is “garbage pit” of engine.
Debris is often forced through the gears and housing.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-13 (a) The oil pump is the only part in an engine that gets unfiltered engine oil. The oil is drawn up from the bottom of the oil pan and is pressurized before flowing to the oil filter.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-13 (b) If debris gets into an oil pump, the drive or distributor shaft can twist and/or break. When this occurs, the engine will lose all oil pressure.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Refer to manufacturer’s specifications
when checking pump for wear– Typical pump clearances
• End plate clearance: 0.0015 in. (0.04 mm)
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Typical pump clearances
• Side (rotor) clearance: 0.012 in. (0.30 mm)
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Typical pump clearances
• Rotor tip clearance: 0.010 in. (0.25 mm)
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Typical pump clearances
• Gear end play clearance: 0.004 in. (0.10 mm)
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Check all parts– Check relief valve for scoring
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PumpsOil Pumps
• Oil Pump Checks– Check condition of relief valve spring– When installing oil pump, coat sealing
surfaces with engine assembly lubricant
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
OIL PASSAGESOIL PASSAGES
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Purpose and Function– Oil from pump first flows through oil filter– Oil then flows through drilled hole to drilled
main oil gallery• Inline engines use one oil gallery
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Purpose and Function– Oil then flows through drilled hole to drilled
main oil gallery• V-type engines may use two or three
galleries
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Purpose and Function– Passages drilled through block bulkheads
allow oil to go from main oil gallery to main and cam bearings
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-14 An intermediate shaft drives the oil pump on this overhead camshaft engine. Note the main gallery and other drilled passages in the block and cylinder head.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Purpose and Function– In some engines, oil goes to cam bearings
first, then to main bearings– Oil holes in bearings must match drilled
passages
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Purpose and Function– Over time, bearings wear– Excess clearance allows excess leakage
around sides of bearings
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Purpose and Function– Little or no oil may be left for bearings
downstream in lubricating system– Bearing failure may result
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Valve Train Lubrication – Oil gallery may intersect or have drilled
passages to valve lifter bores– With hydraulic lifters, oil pressure in gallery
keeps them lubricated
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Valve Train Lubrication – On some engines, oil from lifters goes up
center of hollow pushrod to lubricate pushrod ends, rocker arm pivot, and valve stem tip
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Valve Train Lubrication – In other engines, drilled oil passage from
gallery or cam bearings leads to head gasket hole and drilled hole to carry oil to rocker arm shaft
– Some engines used enlarged bolt hold to rocker arm shaft
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Valve Train Lubrication– Holes in bottom of rocker arm shaft allow
lubrication of rocker arm pivot– Rocker arm assemblies need only surface
coating of oil• Restrictions or metered openings restrict oil
flow
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Valve Train Lubrication– Oil from rocker assemblies returns to oil
pan through drain holes– Oil drain holes often drain oil on camshaft
or cam drive gears
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-15 Oil is sent to the rocker arms on this Chevrolet V-8 engine through the hollow pushrods. The oil returns to the oil pan through the oil drainback holes in the cylinder head.
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Oil PassagesOil Passages
• Valve Train Lubrication– Some engines direct positive oil flow to
cam drive gears or chain• Nozzle
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Oil PassagesOil Passages
• Valve Train Lubrication– Some engines direct positive oil flow to
cam drive gears or chain• Chamfer on bearing parting surface
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
OIL PANSOIL PANS
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
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Oil Pans Oil Pans
• Purpose and Function– Oil pan, or sump, is where engine oil is
used for lubricating engine– Pan baffles and oil pan shapes keep oil inlet
under oil at all times
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
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Oil Pans Oil Pans
• Purpose and Function– Crankshaft rotation can churn oil causing
air bubbles in oil and foaming– Baffle or windage tray is sometimes used to
eliminate oil churning
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23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-16 A typical oil pan with a built-in windage tray used to keep oil from being churned up by the rotating crankshaft.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
DRY SUMP SYSTEMDRY SUMP SYSTEM
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Automotive Technology, Fourth EditionJames Halderman
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Dry Sump SystemDry Sump System
• Construction and Operation– Sump describes location where oil is stored– Most engines hold oil in oil pan; pump
draws oil from bottom
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
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Dry Sump SystemDry Sump System
• Construction and Operation– This system is called a wet sump oil system– Dry sump system uses shallow pan
• Oil is pumped into remote reservoir
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
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Dry Sump SystemDry Sump System
• Construction and Operation– Dry sump system uses shallow pan
• Oil is cooled and trapped air escapes
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Dry Sump SystemDry Sump System
• Construction and Operation– Dry sump system uses shallow pan
• Dry sump uses externally mounted oil reservoir
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Dry Sump SystemDry Sump System
• Advantages– Advantages of dry sump system
• Shallow pan allows engine to be mounted lower, improving cornering
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Dry Sump SystemDry Sump System
• Advantages– Advantages of dry sump system
• Oil capacity can be expanded because reservoir is not limited
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Dry Sump SystemDry Sump System
• Advantages– Advantages of dry sump system
• Vehicle can corner or brake for long periods
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Dry Sump SystemDry Sump System
• Advantages– Advantages of dry sump system
• Engine can develop more power because oil is kept away from crankshaft
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Dry Sump SystemDry Sump System
• Disadvantages– Disadvantages of dry sump system
• Expensive because it needs extra components and plumbing
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Dry Sump SystemDry Sump System
• Disadvantages– Disadvantages of dry sump system
• Complex because it creates more possibilities for oil leaks and changes routine maintenance
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-17 A dry sump system as used in a Chevrolet Corvette.
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
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OIL COOLERSOIL COOLERS
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Oil CoolersOil Coolers
• Larger capacity oil pan helps control oil temperature
• Remote mounted oil coolers– Warm oil in cold weather– Cool oil when engine is hot
23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
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© 2011 Pearson Education, Inc.All Rights Reserved
Oil CoolersOil Coolers
• Oil Temperature– Above 212°F (100°C)– Below 280°F to 300°F (138°C to 148°C)
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23 LUBRICATION SYSTEM OPERATION AND DIAGNOSIS
Automotive Technology, Fourth EditionJames Halderman
© 2011 Pearson Education, Inc.All Rights Reserved
Figure 23-18 Oil is cooled by the flow of coolant through the oil filter adapter.