© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Chapter 13 Engine Sealing and Reassembly

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Torque Principles All metals are elastic Bolts can stretch and compress Stretch applies clamping force Too much stretch destroys the bolt Bolts torqued to yield never return to normal

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.

Torque Principles (Cont.) Most torque values are for dry fasteners Lubricants increase applied torque Visually inspect the bolts Use lubricants or sealers as specified Tighten in the correct sequence Ensure proper fastener is used

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Tightening Sequence Examples

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Threads must be clean and undamaged Use liquid sealant or engine oil on threads Install bolts in their proper holes Run a nut over the bolt’s threads by hand Clean bolt and cylinder block threads with a thread chaser or tap Tighten bolts to the proper torque specification Bolt Installation Tips

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Thread Cleaning

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Thread Repair Overtorquing or incorrect threading will strip threads May be repaired using thread insert or Helicoil

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Torque-To-Yield Bolts TTY fasteners are designed to stretch when properly tightened Once at yield point the bolt is permanently stretched Commonly used as cylinder head bolts Torqued in steps

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. TTY Bolts (Cont.)

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Knowledge Check Why is proper tightening of bolts necessary when installing engine components?

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Gaskets Used to provide a positive seal between parts bolted together Also act as spacers, wear insulators, and vibration dampers Gaskets are used on stationary parts Seals are used with moving parts

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Cut or Soft Gaskets – Made of cork, rubber, or paper Silicone Gasket Material – Three different types Hard Gaskets – Made of steel, copper, or a composite of metal and fiber Sealants – Usually in liquid form Gasket Classifications

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Paper/Fiber Gaskets – low temperature/low pressure Cork Gaskets – not commonly used today Cut Gaskets

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Other Gaskets Molded Rubber Gaskets – retain flexibility and are durable – May have steel insert around bolt holes – Do not use sealants or adhesives Hard Gaskets – made from steel and other materials – Used as cylinder head and exhaust manifold gaskets

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.

Replacement Gaskets Available individually or as sets A full set contains all gaskets necessary for rebuilding an engine Some components are assembled using form in place gaskets Check TSBs for updated gaskets

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Never reuse old gaskets Handle new gaskets carefully Ensure clean mating surfaces General Gasket Installation

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. General Gasket Installation Use the right gasket in the right position Only use sealants when specified Make sure all threads are clean and undamaged

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Head Gaskets – Seals combustion, coolant, and oil – Exposed to very low temperatures to combustion temps of 2000 – 4000 °F – Seals vacuum and combustion pressures (1000 psi peak pressures) – Allows for movement between head and block – Most late model engines use MLS gaskets Specific Engine Gaskets

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. MLS Gasket

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Common Head Gasket Failure Preignition/Detonation – Incorrect timing or mixture, vacuum leak, faulty cooling system Engine Overheating Improper Installation – Wrong head or block surface finish, incorrect bolt tightening, stretched bolts, improper sealant use, incorrect gasket

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.

Specific Engine Gaskets (Cont.) Manifold Gaskets – Intake, exhaust, or combination Valve Cover Gaskets – Must seal between different metals or materials Oil Pan Gaskets – Seal between the block and pan EGR Valve – Gasket may be used to regulate exhaust flow

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Adhesives Used only to hold a gasket in place Do not assembly until adhesive is dry

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Aerobic Sealants – Cure only when exposed to oxygen (air) – Are commonly used to form gaskets Anaerobic Sealants – Cure only in the absence of oxygen (air) – Are used for thread sealant Types of Sealants

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Types of Sealants (Cont.) General Purpose Sealants – Available in liquid, brush on, or aerosol types – Ensure sealant is O 2 sensor safe – Never use a hard drying sealant on gaskets Thread Sealants – Used on bolts passing through a liquid passage

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Types of Sealants (Cont.) Silicone Sealants – Formed-in-place gasket – Applied to mating surfaces – Room Temperature Vulcanizing (RTV) most common – Too much RTV can be squeezed out and into oil system

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Applying RTV

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Antiseize Compounds Prevents dissimilar metals from reacting with each other and seizing Commonly used on aluminum parts Always follow manufacturer recommendations when using

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Knowledge Check Technician A says gaskets are used between moving parts of the engine. Technician B says liquid RTV gasket maker can be used in place of any engine gasket. Who is correct?

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Engine Gaskets and Seals

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Used with rotating parts Three basic types – Fiber-packing – Two-piece lip – One-piece radial Oil Seals

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Oil Seals (Cont.)

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Two-Piece Lip Seal

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Engine Reassembly Clean and lubricate head bolts Match head gasket to block Place head on block and alignment dowels Torque head bolts in sequence Lube pushrods and rocker arms

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Timing Belts and Chains Cam and crank alignment is critical Follow timing procedures exactly Ensure the tensioners apply properly

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Methods of Valve Lash Adjustment Rocker arms with adjustable pivots Adjustable push rods Rocker arms with adjustable screws Adjustable cam followers Selective shims

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Final Assembly Steps Install various covers, pulleys, and sensors Ensure coolant drain plugs are installed Coat sensor O-rings with oil before installing Install vibration damper onto crankshaft Make sure manifold mating surfaces are clean and install manifolds

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Final Assembly Steps (Cont.) Install the thermostat and housing Install the flexplate and torque converter or the flywheel and clutch components Inspect and loosely install motor mounts Install all other related components as necessary

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Knowledge Check What are two methods of adjusting valve lash?

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Always refer to the manufacturer’s service information Prime the oil pump prior to starting the engine Follow the manufacturer’s computer relearn procedures if applicable Engine Installation Tips

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Starting Procedure Set ignition timing as closely as possible Fill fuel tank with several gallons of fresh fuel Start engine and run at 1500 RPM Run until engine reaches normal operating temperature then shut off Recheck all adjustments

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Break-In Procedure Test drive at 30 MPH and accelerate to 50 MPH at full throttle Repeat at least 10 times Apply loads to engine for short periods This helps assure the rings seat

© 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Relearn Procedures The computer will need to learn the engine condition and make adjustments Idle and transmission shift schedules will relearn Reset any memory functions such as the clock and radio presets