Chapter 60 PowerPoint

Define these Technical Terms using the textbook:

1. exhaust manifold

2. head gasket

3. intake manifold

4. intake manifold gasket

5. oil pan

6. oil pump

7. valve adjustment

8. valve cover

Answer these discussion questions using the textbook:

1. The first oil change after an engine rebuild will have a shorter oil change interval than normal. How many miles should you tell the customer to drive the vehicle before bringing it back for its first "post-rebuild" oil change?

Read the chapter summary below:

■ When assembling an engine, all parts must be perfectly clean. Parts should be reinstalled in their same locations. Lubricate moving parts. Make sure bolt lengths are correct. Keep components covered until assembly. Torque all fasteners properly. Inspect everything as it is installed.

■ When installing a used engine oil pump, make sure the pump is in good condition by measuring its internal wear. Many technicians prefer to use a new or factory-rebuilt oil pump any time the pump is removed from the engine.

■ When installing the oil pan, straighten its flange if bent. Adhere the gasket to the pan or block. Use RTV sealer where the end seals overlap the pan gasket.

■ When installing a head gasket, make sure it is facing in the right direction. Markings are normally provided showing the top or front of a head gasket. If dowels are not provided in the engine, install long stud bolts to align the head gasket during assembly.

■ Lower the cylinder head onto the block without hitting the head gasket. Start all of the bolts by hand and turn them down lightly. Use new bolts if they are torque-to-yield fasteners. Use a torque wrench to tighten the head bolts in an approved sequence. Tighten the bolts in steps and at full torque at least twice.

■ Before installing an intake manifold, check mating surfaces for warpage with a straight edge. Also, check the fit of the gasket. Adhere the gasket in place, if needed. If the gasket is a multi-piece, fiber type, simply place a bead of sealer where the gasket and end seals overlap. With a valve cover seal, apply silicone sealer to the ends of the seal where they curve around the ends of the camshaft. Also apply silicone sealer to the round spark plug hole seals to help hold them in place.

■ Place the intake manifold into position without shifting the gasket or end seals. Start all bolts by hand and then torque them to specifications using a criss-cross sequence. Tighten all bolts to 1/2, then 3/4, and finally to full torque twice.

■ Check the exhaust manifold for damage or warpage before installation.

■ Camshaft bearings in an OHC engine may be a one- or two-piece design. One-piece bearings are pressed into the cylinder head. Two-piece bearings snap into the head and camshaft bearing caps.

■ If pushrods extend through the intake manifold, you cannot install the pushrods until the intake manifold is installed. Make sure that the lower end of each pushrod is installed fully into its lifter.

■ After installation of the valvetrain components, you may have to adjust the clearance in the valvetrain. If the valves are too loose, valvetrain noise will result.

■ Non-adjustable rocker arms are used on some pushrod engines with hydraulic lifters. The hydraulic lifters automatically compensate for changes in valvetrain clearance to maintain a zero valve lash. If adjustment is needed, torquing the rocker arm nut or bolt to specifications normally adjusts the valvetrain clearance. Different pushrod lengths can sometimes be purchased.

■ With some OHV engine designs, you must adjust the rocker arms to center the hydraulic lifter plungers. Centering the lifter plungers in their bores allows the lifters to automatically adjust to take up or allow more valvetrain clearance.

■ There are many methods of adjusting valvetrain clearance on OHC engines. OHC engines may have self-adjusting hydraulic cam followers, valve adjusting shims, or an adjusting screw in the cam followers.

■ Before installing a valve cover, make sure the cover flange is not bent. Adhere the gasket to the cover or use a continuous bead of silicone in place of the gasket. Make sure the mating surface on the cylinder is clean, and then carefully lower the cover into place.Start all bolts by hand and then tighten them in a criss-cross sequence. Over-tightening valve cover bolts can bend the cover or split the gasket.

■ Final engine assembly involves installing the flywheel and clutch or torque converter, as well as attaching external components, such as brackets or sensors.

■ Before installing the flywheel, check its ring gear teeth for damage.

■ When installing the torque converter, make sure it is completely seated over its shaft.

■ When preparing to install the engine, make sure all needed parts are close by. Engine installation is basically the reverse of engine removal. Keep the engine crankshaft and transmission or transaxle input shaft in perfect alignment during installation. Do not use the bellhousing bolts to force the transmission against the engine. Make sure all external parts are installed.

■ After the engine is secured in the vehicle, fill the engine with motor oil, the radiator with coolant, and the transmission or transaxle with fluid.

■ For engine start-up, start and fast idle the engine. Check oil pressure and do not let the engine overheat. Let the engine run at fast idle and watch for leaks.

■ Engine break-in is done to seat and seal new piston rings and wear in other components. Test drive the vehicle, accelerating and decelerating several times.

■ Advise the vehicle owner about driving methods after an engine overhaul.