1. Engine Removal and Disassembly
Chapter 50

2. Objectives Label and organize parts prior to engine removal
Remove an engine from a vehicle in a safe and methodical manner
Disassemble the engine following the correct procedures
Keep parts organized for reassembly
Inspect and interpret causes internal engine wear

3. Introduction Procedures must be followed carefully
Parts must be removed and inspected in an orderly manner
You cannot hurry
Signs of wear can be clues
Correct repair will prevent the problem from occurring again
Be sure to consult the applicable repair manual
Procedures differ

4. Engine Removal Important steps Disconnect battery cables
Remove the hood
Remove air cleaner
Label all wires and vacuum lines
Drain coolant and oil
Remove the radiator
Remove the distributor and spark plug wiring
Remove the direct current (DC) generator
Remove the heater hoses and ground strap

7. Engine Removal (cont'd.)
Remove switches and sensors
Remove the throttle linkage, cable, or wiring
Mark accessory brackets and remove accessories
Remove exhaust components
Remove and plug the fuel line
Determine whether to remove the transmission
Separate the engine and transmission/transaxle
Unbolt the engine mounts

9. Engine Removal (cont'd.)
Remove the engine from the vehicle
Remove transaxle (if necessary)
Remove lower ball joints
Have drain pan ready
Disconnect speedometer cable, transmission shift linkage, and clutch cable
Attach a sling to the engine and transaxle assembly
Remove bolts
Roll shop crane until the engine can be lowered safely

10. Engine Disassembly Important steps Remove clutch parts
Remove hybrid armature (puller required)
Mount engine to a stand
Remove coolant pump
Remove oil pan
Remove valve covers
Slip a knife blade between head and sheet metal valve cover
Tap a curved, strong area with a rubber mallet

11. Engines with Pushrods Stud mounted rockers
Loosen nuts on studs before disassembly and cleaning
Turn rocker arms to the side to remove the pushrods
After heads are cleaned they can be removed one at a time
Keep pushrods in order

12. Engines with Pushrods (cont'd.)
Shaft-mounted rockers
Should be loosened slowly and evenly
Remove the pushrods
Pushrods can be pushed through holes made in a piece of cardboard
Pushrods must be kept in order

13. Engines with Pushrods (cont'd.)
Valve lifters
Remove valve lifters
Wipe oil off bottom of lifters
Label with a felt marker
Reused flat tappers must be used on original cam lobe
Usually replaced
Roller lifters are usually reusable
Use chemical cleaner to soften varnish

16. Engines with Pushrods (cont'd.)
Pushrod engine camshaft
Some pushrod engines use bolt-on cam thrust plate
Varnish may builds up on edges of cam journals
Makes it difficult to remove the cam
Vibration damper removal
Most engines have a bolt that holds it on the crankshaft
Some will slip off after the bolt is removed
Others are pressed-fit

17. Overhead Cam Cylinder Head Removal
Important steps
Position the number one piston at TDC and note the location of timing marks
Compare the sketch in the repair manual to the marks on the timing belt
Draw a sketch of the cam timing
Remove timing cover

19. Overhead Cam Engines (cont'd.)
Remove the cam drive assembly
Pushrod engines
Unbolt cam sprocket and slide or pry off the cam
Remove the chain
Reinstall sprocket and tighten one bolt finger tight
Overhead cam engines
Remove the chain or bolt tensioner

21. Overhead Cam Engines (cont'd.)
Remove the cylinder heads
Mark one of the cylinder heads “left” or “right” if there is more than one
Be careful not to break a casting
Inspect the head gasket
Evidence of coolant or oil leakage
Signs of detonation

22. Cylinder Block Disassembly
Modern engines use premium piston rings
Will not accommodate a worn cylinder bore
Ridge causes
Pressure of combustion forcing the piston ring against the cylinder wall
Lack of clean lubrication at the top of the cylinder

23. Cylinder Block Disassembly (cont'd.)
Important steps
Turn engine over and mark main caps and rod caps
Main caps must be installed in one direction only
Connecting rods and caps are mated to one another and must be marked for identification
Remove and inspect the piston and rod assembly
Inspect the piston, rings, rod, and bearings
Remove the crankshaft and inspect for wear
Remove the camshaft

25. Cylinder Block Disassembly (cont'd.)
Remove and label cam bearings
Remove core plugs
Clean engine parts
Remove the crank sprocket or gear
Finish diagnosis and repair of engine assembly