Standard

AUT 126 - ENGINE PRINCIPLES OF OPERATION AND REPAIR

Course Description

Introduces automotive engine theory and repair, placing emphasis on inspection, testing, and diagnostic techniques. Topics include: general diagnosis; removal and reinstallation; cylinder heads and valve trains diagnosis and repair; engine blocks assembly diagnosis and repair; lubrication and cooling systems diagnosis and repair.

Competency Areas		Hours
General Engine Diagnosis; Removal and Reinstallation (R&R)		Class	3
Cylinder Head and Valve Train Diagnosis and Repair		D. Lab	0
Engine Blocks Assembly Diagnosis and Repair		P. Lab/O.B.I.	9
Lubrication and Cooling Systems Diagnosis and Repair		Credit	6
Prerequisite:	AUT 120
Corequisite:

Course Guide

Competency	After completing this section, the student will:	Hours
		Class	D.Lab	P.Lab/ O.B.I.
General Engine Diagnosis; Removal and Reinstallation (R&R)		10		15
	Verify and interpret engine concern; determine necessary action. Inspect engine assembly for fuel, oil, coolant, and other leaks; determine necessary action. Diagnose engine noises and vibrations; determine necessary action. Diagnose the cause of excessive oil consumption, unusual engine exhaust color, odor, and sound; determine necessary action. Perform engine vacuum tests; determine necessary action. Perform cylinder power balance tests; determine necessary action. Perform cylinder compression tests; determine necessary action. Perform cylinder leakage tests; determine necessary action. Remove engine (front-wheel drive); prepare for disassembly. Reinstall engine (front-wheel drive). Remove engine (rear-wheel drive); prepare for disassembly. Reinstall engine (rear-wheel drive).
Cylinder Head and Valve Train Diagnosis and Repair		10		32
	Remove cylinder head(s); visually inspect cylinder head(s) for cracks; check gasket surface areas for warpage and leakage; check passage condition. Install cylinder heads and gaskets; tighten according to manufacturer’s specifications and procedures Inspect and test valve springs for squareness, pressure, and free height comparison; replace as needed. Inspect valve spring retainers, locks, and valve grooves. Replace valve stem seals. Inspect valve guides for wear; check valve guide height and stem-to-guide clearance; recondition or replace as needed. Resurface valves; perform necessary action. Resurface valve seats; perform necessary action. Check valve face-to-seat contact and valve seat concentricity (runout); service seats and valves as needed. Check valve spring assembled height and valve stem height; service valve and spring assemblies as needed. Inspect pushrods, rocker arms, rocker arm pivots and shafts for wear, bending, cracks, looseness, and blocked oil passages (orifices); perform necessary action. Inspect hydraulic or mechanical lifters; replace as needed. Adjust valves (mechanical or hydraulic lifters). Inspect camshaft drives (including gear wear and backlash, sprocket and chain wear); replace as necessary. Inspect and replace timing belt(s), overhead camdrive sprockets, and tensioners; check belt tension; adjust as necessary. Inspect camshaft for runout, journal wear and lobe wear. Inspect and measure camshaft bearings for wear, damage, out-of-round, and alignment; determine necessary action. Verify camshaft(s) timing according to manufacturer’s specifications and procedure.
Engine Blocks Assembly Diagnosis and Repair		5		32
	Inspect and replace pans, covers, gaskets, and seals. Inspect engine block for visible cracks, passage condition, core and gallery plug condition, and surface warpage; determine necessary action. Inspect internal and external threads; restore as needed (includes installing thread inserts). Remove cylinder wall ridges. Inspect and measure cylinder walls for damage and wear; determine necessary action. Deglaze and clean cylinder walls. Inspect and measure camshaft bearings for wear, damage, out-of-round, and alignment; determine necessary action. Inspect crankshaft for surface cracks and journal damage; check oil passage condition; measure journal wear; determine necessary action. Inspect and measure main and connecting rod bearings for damage, clearance, and end play; determine necessary action (includes the proper selection of bearings). Identify piston and bearing wear patterns that indicate connecting rod alignment and main bearing bore problems; inspect rod alignment and bearing bore condition. Inspect, measure, and service pistons and pins; determine necessary action. Inspect, measure, and install piston rings. Inspect, repair or replace crankshaft vibration damper (harmonic balancer) Reassemble engine components using correct gaskets and sealants. Inspect auxiliary (balance, intermediate, idler, counterbalance or silencer) shaft(s); inspect shaft(s) and support bearings for damage and wear; determine necessary action; reinstall and time. Prime engine lubrication system.
Lubrication and Cooling Systems Diagnosis and Repair		5		11
	Prime engine lubrication system. Inspect oil pump gears or rotors, housing, pressure relief devices, and pump drive; perform necessary action. Perform cooling system, cap, and recovery system tests (pressure, combustion leakage, and temperature); determine necessary action. Inspect, replace, and adjust drive belts, tensioners, and pulleys. Inspect and replace engine cooling and heater system hoses. Inspect, test, and replace thermostat and housing. Test coolant; drain and recover coolant; flush and refill cooling system with recommended coolant; bleed air as required. Inspect, test, remove, and replace water pump. Remove and replace radiator. Inspect, and test fans(s) (electrical or mechanical), fan clutch, fan shroud, and air dams. Inspect auxiliary oil coolers; replace as needed. Inspect, test, and replace oil temperature and pressure switches and sensors. Perform oil and filter change.

Suggested Resources

Books

Duffy, J. E. (2000). Modern AutomotiveTechnology. South Holland, IL: Goodheart-Willcox.

Erjavec, J. (2000). Automotive Technology (3^rd ed.). Albany, NY: Delmar.

Erjavec, J. (2000). Automotive Technology Workbook (3^rd ed.). Albany, NY: Delmar.

Gilles, T. (1999). Automotive Service Inspection, Maintenance, and Repair (1^st ed.). Albany, NY: Delmar

Toboldt, W. K., & Johnson, L. (1995). Automotive Encyclopedia. South Holland, IL: Goodheart-Willcox.

Webster, J., & Owen, C. E. (2000). Basic Automotive Service & Systems (2^nd ed.).

Albany, NY: Delmar.