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Engine Installation, Break-In,
and In-Chassis Repairs
Chapter 56
© 2012 Delmar, Cengage Learning
Objectives
• Install an engine in a vehicle
• Pre-lube and make all required adjustments
prior to starting an engine
• Inspect and complete the job following engine
starting and break-in
• Overhaul an engine while it is in the vehicle
© 2012 Delmar, Cengage Learning
Introduction
• This chapter describes:
– How to install an engine in a vehicle
• After installation, certain procedures are followed
to break it in
– Some repairs done to an engine while it is in the
vehicle
© 2012 Delmar, Cengage Learning
Engine Installation and Install
Engine Mounts
• Engine installation
– Be sure fender covers are installed
– Be careful when using a chain hoist
• Chain may nick the car’s paint
• Install engine mount
– Install bolts loosely on the block
– Mounts are more easily aligned with frame mount
brackets
© 2012 Delmar, Cengage Learning
Install the Engine
• Major steps
– Raise and position engine in the engine
compartment
– Use a rolling head prybar when aligning bolts
– Bolt the engine to the transmission housing
– Install all previously disconnected parts
– Install fuel system components
– Install oil filter and add oil
© 2012 Delmar, Cengage Learning
© 2012 Delmar, Cengage Learning
Priming the Lubrication System
• Prime the system by driving the oil pump
– Drive tool with a slow drill
– Engines with hydraulic filters or cam followers
• Turn pump until pressure builds
• Turn crankshaft one complete revolution
– Turn the pump once more
• Distributor must have gear on bottom of its shaft
– Otherwise oil pump priming will be impossible
© 2012 Delmar, Cengage Learning
© 2012 Delmar, Cengage Learning
Pressure Priming
• Not possible to prime by removing distributor
– Use a pressure primer
– Remove all spark plugs and crank engine
• Pressure primer uses
–
–
–
–
Prime the system
Check excessive bearing clearance
Check for sufficient oil pressure
Flush oil galleries during in-car engine repair
• Remove oil pan and block off oil pump inlet
– Some pumps must be filled with assembly lube
© 2012 Delmar, Cengage Learning
Install Valve Covers
• Oil is apparent at some of the rocker arms
– Install valve covers
• Oil is not reaching the valve area during priming
– Double-check to see that an internal oil leak does
not exist
• Before installing the valve covers
– Easier to position the engine at top dead center
(TDC) on number one
© 2012 Delmar, Cengage Learning
Ignition System Installation and
Timing
• Predominant designs
– Distributor and
distributorless
• Major steps
– Align timing mark on
damper with pointer
on timing cover
– Before starting engine:
fill coolant overflow
reservoir at least half
full
© 2012 Delmar, Cengage Learning
Engine Starting and Initial
Break-In
• First few minutes of operation are critical
– Temperatures must be controlled
• When engine is first run, check:
– Oil pressure
– Coolant temperature
– Oil leaks
• Shut engine off immediately if adjustments are
needed
© 2012 Delmar, Cengage Learning
Valve Clearance Adjustment
• Mechanical valve clearance adjustment
– Clearance set during engine assembly
– Done with engine off
• Attempting an overhead cam (OHC) adjustment
with the engine running can be messy
© 2012 Delmar, Cengage Learning
Road Test and Break-in
• Take safety precautions before the test drive
– Double-check hose connections and fluid levels
– With key off, push accelerator to WOT
• Seat the piston rings
– Drive on freeway
– In high gear:
• Accelerate from 45mph to 50mph
• Coast back to 45 mph several times
– May take 2,000 to 3,000 miles to seat the rings
© 2012 Delmar, Cengage Learning
Final Inspection
• Major steps
– Double-check the engine for oil leaks
– Make certain all wires and lines have been
correctly installed
– Check all warning lights or gauges are operating
properly
– If malfunction indicator comes on, determine
cause of DTC and repair
© 2012 Delmar, Cengage Learning
Returning the Car to the
Customer
• Major considerations
– Return in a clean condition
– Raise the hood and explain what was done
– Return to shop after 500 miles for checkup
• Customer break-in procedures
– No excessive engine idle for first three hours
•
•
•
•
Keep in normal rpm range: first two to three hours
Engine speed: should vary
Full load or high-speed operation: should be limited
After high-load operation: allow engine to return to
a stable operating temperature
© 2012 Delmar, Cengage Learning
Engine Repair-Engine in the
Vehicle
• Technicians often perform major repairs to an
engine while it is in the vehicle
– Rebuilding cylinder heads
– Lower end work
– Overhaul: piston ring and crank bearing
replacement
• OHC engines
– Many require a new chain tensioner
© 2012 Delmar, Cengage Learning
Valve Job or Head Gasket
Repairs
• Major steps
– Unbolt head in direction opposite to normal
tightening sequence
– Check cleanliness of head bolt threads
– Be careful that nothing is accidentally pinched
between head and block when reinstalling
– Maintain valve timing
• Keep the timing chain or belt in place
© 2012 Delmar, Cengage Learning
© 2012 Delmar, Cengage Learning
Valve Job or Complete Engine
Overhaul and Head Gasket
Problems
• Valve guide seals
– Responsible for some oil consumption
complaints
• Inspect head gasket for damage
– Excessive temperatures can turn a metal head
gasket blue or black
– Teflon® gaskets can turn brown
– Look for signs of coolant leaks
© 2012 Delmar, Cengage Learning
In-Chassis Lower End Repairs
• Low-mileage engine
– Often repaired without
removing the engine
– Engine hoist can be
used to raise engine
and remove oil pan
© 2012 Delmar, Cengage Learning
Removing the Oil Pan
• Removing oil pan
– Could require removal of some steering linkage
© 2012 Delmar, Cengage Learning
Remove the Piston and Rod
Assembly
• Major steps
– Lower end is to be repaired: remove cylinder
heads
– In-car repair might call for replacement of one
defective piston
– Main bearings are replaced with the crankshaft in
the engine
– Bearings must be rolled out on side opposite
bearing locating lug
© 2012 Delmar, Cengage Learning
© 2012 Delmar, Cengage Learning
Remove the Timing Cover
• Major steps
– Remove radiator
– Remove accessory drive belts
– Remove vibration damper
• Service on belt drives
– Relatively simple
• Removing timing cover on some OHC engines
with timing chains is more difficult
© 2012 Delmar, Cengage Learning
Free-Wheeling and Interference
Engines
• Freewheeling
– An engine that has enough piston-to-valve
clearance to prevent contact
• Before a chain repair job
– Perform a leakage test on non-freewheeling
engines
• Check for bent valves
© 2012 Delmar, Cengage Learning
Replace the Timing Components
and Crankshaft Seal Replacement
• Reinstalling the head on an OHC engine
– Number one piston is at TDC and cam is
properly timed
• Drive sprockets
– Replaced with engine in the car
• Crankshaft front and rear seal replacements
– Performed with engine in the car
© 2012 Delmar, Cengage Learning
Flywheel Ring Gear Service
• Most vehicles with standard transmissions have
a replaceable ring gear on flywheel
– Flywheel ring gear can be worn by a defective
starter motor drive
• Heat the new ring gear evenly around its
circumference during installation
– Tempilstick® checks ring gear temperature
– Polishing and solder can also be used to check
temperature of ring gear
© 2012 Delmar, Cengage Learning
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