Chrysler PT Cruiser. Manual — part 708
(5) Install ignition coil and spark plug wires.
Tighten fasteners to 12 N·m (105 in. lbs.).
(6) If the PCV valve was removed, apply Mopar
t
Thread Sealant with Teflon to threads and install
valve to cylinder head cover. Tighten PCV valve to 8
N·m (70 in. lbs.).
(7) Connect PCV and make-up air hoses to cylin-
der head cover (Fig. 44).
(8) Install upper intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE
MANIFOLD
-
INSTALLATION).
HYDRAULIC LASH
ADJUSTERS
DIAGNOSIS AND TESTING
HYDRAULIC LASH ADJUSTER NOISE
DIAGNOSIS
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
(2) Insufficient running time after rebuilding cylin-
der head. Low speed running up to 1 hour may be
required.
(3) During this time, turn engine off and let set for
a few minutes before restarting. Repeat this several
times after engine has reached normal operating
temperature.
(4) Low oil pressure.
(5) The oil restrictor (integral to the cylinder head
gasket) in the vertical oil passage to the cylinder
head is plugged with debris.
(6) Air ingested into oil due to broken or cracked
oil pump pick up.
(7) Worn valve guides.
(8) Rocker
arm
ears
contacting
valve
spring
retainer.
(9) Rocker arm loose, adjuster stuck or at maxi-
mum extension and still leaves lash in the system.
(10) Faulty lash adjuster.
• Check lash adjusters for sponginess while
installed in cylinder head. Depress part of rocker
arm over adjuster. Normal adjusters should feel very
firm. Spongy adjusters can be bottomed out easily.
• Remove suspected lash adjusters, and replace as
necessary.
REMOVAL
NOTE: This procedure is for in-vehicle service with
camshafts installed.
(1) Remove cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER
HEAD/CYLINDER
HEAD
COVER(S) - REMOVAL)
(2) Remove rocker arm. (Refer to 9 - ENGINE/
CYLINDER HEAD/ROCKER ARMS - REMOVAL)
(3) Remove hydraulic lash adjuster (Fig. 50).
(4) Repeat removal procedure for each hydraulic
lash adjuster.
(5) If reusing, mark each hydraulic lash adjuster
for reassembly in original position. Lash adjusters
are serviced as an assembly.
INSTALLATION
(1) Install
hydraulic
lash
adjuster
(Fig.
50).
Ensure the lash adjusters are at least partially full of
engine oil. This is indicated by little or no plunger
travel when the lifter is depressed.
(2) Install rocker arm. (Refer to 9 - ENGINE/CYL-
INDER HEAD/ROCKER ARMS - INSTALLATION)
(3) Repeat installation procedure for each hydrau-
lic lash adjuster.
(4) Install cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER
HEAD/CYLINDER
HEAD
COVER(S) - INSTALLATION)
INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The valves are made of heat resistant steel. They
have chrome plated stems to prevent scuffing. Viton
rubber valve stem seals are integral with the spring
seats. The valves have three-bead lock keepers to
retain springs and to promote valve rotation.
Fig. 50 Hydraulic Lash Adjuster
9 - 112
ENGINE 2.4L DOHC
PT
CYLINDER HEAD COVER (Continued)
OPERATION
The four valves per cylinder (two intake and two
exhaust) are opened by using roller rocker arms
which pivot on hydraulic lash adjusters.
CLEANING
(1) Clean
all
valves
thoroughly
and
discard
burned, warped and cracked valves.
ROCKER ARMS
REMOVAL
NOTE: This procedure is for in-vehicle service with
camshafts installed.
(1) Remove cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER
HEAD/CYLINDER
HEAD
COVER(S) - REMOVAL)
(2) Remove spark plugs.
(3) Rotate engine until the camshaft lobe, on the
follower being removed, is positioned on its base cir-
cle (heel). Also, the piston should be a minimum of
6.3 mm (0.25 in) below TDC position.
CAUTION: If cam follower assemblies are to be
reused, always mark position for reassembly in
their original positions.
(4) Using Special Tools 8215A and 8436 slowly
depress valve assembly until rocker arm can be
removed (Fig. 51).
(5) Repeat removal procedure for each rocker arm.
INSPECTION
Inspect the rocker arm for wear or damage (Fig.
52). Replace as necessary.
INSTALLATION
(1) Lubricate rocker arm with clean engine oil.
(2) Using Special Tools 8215A and 8436 slowly
depress valve assembly until rocker arm can be
installed on the hydraulic lifter and valve stem (Fig.
51).
(3) Repeat installation procedure for each rocker
arm.
(4) Install spark plugs.
(5) Install cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER
HEAD/CYLINDER
HEAD
COVER(S) - INSTALLATION)
Fig. 51 Rocker Arm - Removal/Installation
1 - SPECIAL TOOL 8215A
2 - SPECIAL TOOL 8436
3 - 3/8
9
DRIVE RACHET
Fig. 52 Rocker Arm
1 - TIP
2 - LASH ADJUSTER POCKET
3 - ROLLER
PT
ENGINE 2.4L DOHC
9 - 113
INTAKE/EXHAUST VALVES & SEATS (Continued)
VALVE SPRINGS & SEALS
REMOVAL
CYLINDER HEAD ON
(1) Remove cylinder head cover (Refer to 9 -
ENGINE/CYLINDER
HEAD/CYLINDER
HEAD
COVER(S) - REMOVAL).
(2) Remove camshafts (Refer to 9 - ENGINE/CYL-
INDER HEAD/CAMSHAFT(S) - REMOVAL).
(3) Rotate crankshaft until piston is at TDC on
compression.
(4) With air hose attached to adapter tool installed
in spark plug hole, apply 90-120 psi air pressure.
(5) Using Special Tool MD-998772-A with adapter
6779 (Fig. 53), compress valve springs and remove
valve locks.
(6) Remove valve spring(s).
(7) Remove valve stem seal(s) by a using valve
stem seal tool (Fig. 55).
CYLINDER HEAD OFF
(1) With cylinder head removed from cylinder
block, compress valve springs using a universal valve
spring compressor.
(2) Remove valve retaining locks, valve spring
retainers, valve stem seals and valve springs.
(3) Before removing valves, remove any burrs
from valve stem lock grooves to prevent dam-
age to the valve guides. Identify valves, locks and
retainers to insure installation in original location.
(4) Inspect the valves. (Refer to 9 - ENGINE/CYL-
INDER HEAD/VALVE SPRINGS - INSPECTION)
INSPECTION
(1) Whenever valves have been removed for inspec-
tion, reconditioning or replacement, valve springs
should be tested for correct tension. Discard the
springs that do not meet specifications. The following
specifications apply to both intake and exhaust
valves springs:
• Valve Closed Nominal Tension—75 lbs. @ 38.0
mm (1.50 in.)
• Valve Open Nominal Tension—134 lbs. @ 29.75
mm (1.17 in.)
(2) Inspect each valve spring for squareness with a
steel square and surface plate, test springs from both
ends. If the spring is more than 1.5 mm (1/16 inch)
out of square, install a new spring.
INSTALLATION
CYLINDER HEAD ON
(1)
Install valve seal/valve spring seat assembly
(Fig. 54). Push the assembly down to seat it onto the
valve guide.
(2)
Install valve spring and retainer, use Special
Tool MD-998772-A with adapter 6779 to compress
valve springs only enough to install locks (Fig. 53).
Correct alignment of tool is necessary to avoid nick-
ing valve stems.
(3)
Remove air hose and install spark plugs.
(4)
Install camshafts (Refer to 9 - ENGINE/CYL-
INDER HEAD/CAMSHAFT(S) - INSTALLATION).
(5) Install cylinder head cover (Refer to 9 -
ENGINE/CYLINDER
HEAD/CYLINDER
HEAD
COVER - INSTALLATION).
Fig. 53 Valve Spring - Removal/Installation
1 - VALVE SPRING COMPRESSOR MD 998772A
2 - AIR HOSE
Fig. 54 Valve Stem Seal/Valve Spring Seat
1 - VALVE RETAINING LOCKS
2 - VALVE SPRING
3 - VALVE SEAL AND VALVE SPRING SEAT ASSEMBLY
4 - VALVE SPRING RETAINER
9 - 114
ENGINE 2.4L DOHC
PT
CYLINDER HEAD OFF
(1)
Coat valve stems with clean engine oil and
insert in cylinder head.
(2)
Install new valve stem seals on all valves
using a valve stem seal tool (Fig. 55). The valve stem
seals should be pushed firmly and squarely over
valve guide.
CAUTION: When oversize valves are used, the cor-
responding oversize valve seal must also be used.
Excessive guide wear may result if oversize seals
are not used with oversize valves.
(3)
Install valve springs and retainers. Compress
valve springs only enough to install locks, taking
care not to misalign the direction of compression.
Nicked valve stems may result from misalignment of
the valve spring compressor.
CAUTION: When depressing the valve spring retain-
ers with valve spring compressor the locks can
become dislocated. Ensure both locks are in the
correct location after removing tool.
(4) Check the valve spring installed height B after
refacing the valve and seat (Fig. 56). Make sure mea-
surements are taken from top of spring seat to the
bottom surface of spring retainer. If height is greater
than 38.75 mm (1.525 in.), install a 0.762 mm (0.030
in.) spacer under the valve spring seat to bring
spring height back within specification.
ENGINE BLOCK
DESCRIPTION
The cast iron cylinder block is a two-piece assem-
bly, consisting of the cylinder block and bed plate
(Fig. 57). The bed plate incorporates the main bear-
ing caps and bolts to the cylinder block. This design
offers a much stronger lower end and increased cyl-
inder block rigidity. The rear oil seal retainer is inte-
gral with the block. The bed plate and block are
serviced as an assembly.
STANDARD PROCEDURE
CYLINDER BORE HONING
(1) Used carefully, the cylinder bore resizing hone,
recommended tool C-823 or equivalent, equipped
with 220 grit stones, is the best tool for this honing
procedure. In addition to deglazing, it will reduce
taper and out-of-round as well as removing light
scuffing, scoring or scratches. Usually a few strokes
will clean up a bore and maintain the required lim-
its.
(2) Deglazing of the cylinder walls may be done
using a cylinder surfacing hone, recommended tool
C-3501 or equivalent, equipped with 280 grit stones,
if the cylinder bore is straight and round. 20–60
strokes depending on the bore condition, will be suf-
ficient to provide a satisfactory surface. Use a light
honing oil. Do not use engine or transmission oil,
Fig. 55 Valve Stem Oil Seal Tool
1 - VALVE SEAL TOOL
2 - VALVE STEM
Fig. 56 Checking Spring Installed Height and Valve
Tip Height Dimensions
1 - GARTER SPRING
2 - VALVE SPRING SEAT
3 - CYLINDER HEAD SURFACE
Fig. 57 Cylinder Block and Bed plate
1 - CYLINDER BLOCK
2 - BED PLATE
PT
ENGINE 2.4L DOHC
9 - 115
VALVE SPRINGS & SEALS (Continued)
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