Engine Rebuilding Ch 18.
Engine Rebuilding Ch 18. Auto 111
College of Lake County
Popular in Engine Rebuilding
Popular in Department
This 3 page Class Notes was uploaded by Amber Notetaker on Thursday September 29, 2016. The Class Notes belongs to Auto 111 at College of Lake County taught by Chess in Fall 2016. Since its upload, it has received 3 views.
Reviews for Engine Rebuilding Ch 18.
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 09/29/16
Ch. 18 Gasoline Engine Operation, Parts, and Specifications Convert heat energy of burning fuel into mechanical energy Mechanical energy is used to perform the following: o Propel the vehicle o Power the air-conditioning system and power steering o Produce electrical power for use throughout the vehicle Engines use energy to produce power Combustion-fuel is burned at a controlled rate to convert chemical energy to heat energy Combustion occurs within the power chamber in an internal combustion engine Engines in automobiles are internal combustion heat engines NOTE: An external combustion engine burns fuel outside of the engine itself, such as a steam engine Block o Solid frame from which all automotive and truck engines are constructed o Constructed of cast iron or aluminum Rotating Assembly o Constructed of pistons, connecting rods and a crankshaft Cylinder Heads o Seal top of cylinders in the engine block o Contain both intake valves and exhaust valves o Constructed of cast iron or aluminum Intake and Exhaust Manifolds o Air and fuel enter and exit the engine through manifolds o Intake manifolds are constructed of nylon-reinforced plastic or aluminum o Exhaust manifolds must withstand hot gases and are constructed of cast iron or steel tubing Cooling System o Controls engine temperature o Vehicles are cooled by circulating antifreeze coolant o Coolant picks up heat and releases it through radiator Lubrication System o Oil pumped from oil pan through oil filter, then into oil galleries to lubricate engine parts Fuel System and Ignition System o Fuel Tank-stores fuel and contains most fuel pumps o Fuel filter and lines-transfer fuel for the fuel tank to the engine o Fuel injectors-spray fuel into intake manifold or directly into the cylinder o Spark plugs- provide an air gap inside the cylinder where a spark occurs to start combustion o Sensor(s)- includes crankshaft position (CKP) and camshaft position (CMP) o Ignition coils-increase battery voltage to 5,000-40,000 volts o Ignition control module (ICM)- controls when the spark plugs fires o Associated wiring-electrically connects the battery, ICM, coil, and spark plugs Four-Stroke Cycle Operation o Engine cycles are identified by the number of piston strokes required to complete the cycle o Piston Stroke-one-way piston movement o Most engines use a four-stroke cycle o Intake Stroke o Compression stroke o Power stroke o Exhaust stroke The 720-degree cycle o In each cycle, the engine crankshaft makes two complete revolutions (or 720 degrees) o To fine the angle between cylinders of an engine, divide the number of cylinders into 720 Engines are classified by number of strokes, and cylinder arrangement, longitudinal and transverse mounting, valve and camshaft number and location, type of fuel, cooling method, type of induction pressure Push rod engine-camshaft is located in the block, the valves are operated by lifters, pushrods, and rocker arms Push rod engines are called cam-in-block design and overhead valve (OHV) Single overhead camshaft (SOHC) design uses one overhead camshaft Double overhead camshaft (DOHC) design uses two overhead camshafts Engine Rotation Direction- SAE standard for automotive engine rotation is counterclockwise (CCW) Direction is viewed from the flywheel end (principal end) of the engine (end to which power is applied to drive vehicle) Non-principal end is referred to as the front end and is opposite the flywheel end Bore o Diameter of a cylinder o Pressure measure in units, such as pounds per square inch (PSI) Stroke o Distance the piston travels from top dead center (TDC) to bottom dead center (BDC) o Determine by the throw of the crankshaft o The throw is the distance from the centerline of the crankshaft to the centerline of the crankshaft rod journal o The throw is one-half of the stroke Displacement o Displacement (engine size) is the cubic inch (cu. In.) or cubic centimeter (cc) volume displaced or how much air is moved by all of the pistons o Most engines today are identified by their displacement 1L = 1,000 cc 1L= 61 cu.in 1 cu.in = 16.4 cc Cubic inches = 226 cubic inches Changing Compression Ratio o Factors that can affect compression ratio: Head gasket thickness Increasing cylinder size Definition of Torque o Rotating force that may or may not result in motion o Measured as the amount of force multiplied by the length of the level through which it acts o Twisting force measure at the end of the crankshaft and measure on a dynamometer o Engine torque is always expressed at a specific engine speed (RPM) or range of engine speeds o Metric unit for torque is newton-meters Definition of Power o Rate of doing work o Power equals work divided by time o Power is expressed in units of foot-pounds per minute and power includes the engine speed (RPM) where the maximum power is achieved Horsepower and Altitude o Power that a normal engine can develop is greatly reduced at high altitude o
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'