Jeep Liberty KJ. Manual — part 887
VALVES & SEATS - INTAKE/EXHAUST
DESCRIPTION
The valves are made of heat resistant steel and have chrome plated stems to prevent scuffing. Each valve is actu-
ated by a roller rocker arm which pivots on a stationary lash adjuster. All valves use three bead lock keepers to
retain the springs and promote valve rotation.
STANDARD PROCEDURE - REFACING
NOTE: Valve seats that are worn or burned can be
reworked, provided that correct angle and seat
width are maintained. Otherwise the cylinder head
must be replaced.
NOTE: When refacing valves (4) and valve seats, it
is important that the correct size valve guide pilot
be used for reseating stones. A true and complete
surface must be obtained.
1. Using a suitable dial indicator measure the center
of the valve seat. Total run out must not exceed
0.051 mm (0.002 in).
2. Apply a small amount of Prussian blue to the valve
seat, insert the valve into the cylinder head, while
applying light pressure on the valve rotate the
valve. Remove the valve and examine the valve
face. If the blue is transferred below the top edge
of the valve face, lower the valve seat using a 15
degree stone. If the blue is transferred to the bot-
tom edge of the valve face, raise the valve seat
using a 65 degree stone.
3. When the seat is properly positioned the width of the intake seat must be 1.75 - 2.36 mm (0.0689 - 0.0928 in.)
and the exhaust seat must be 1.71 - 2.32 mm (0.0673 - 0.0911 in.).
4. Check the valve spring (6) installed height after refacing the valve and seat. The installed height for both intake
and exhaust valve springs must not exceed 40.74 mm (1.6039 in.).
5. The valve seat and valve face must maintain a face angle of 44.5 - 45 ° angle.
9 - 1506
ENGINE - 3.7L
KJ
REMOVAL
NOTE: The cylinder heads must be removed in
order to perform this procedure.
1. Remove rocker arms and lash adjusters (Refer to 9
-
ENGINE/CYLINDER
HEAD/ROCKER
ARM
/
ADJUSTER ASSY - REMOVAL).
2. Remove the camshaft bearing caps and the cam-
shaft.
NOTE: All valve springs and valves are removed in
the same manner; this procedure only covers one
valve and valve spring.
3. Using Special Tool C-3422–B or C-3422–C Valve
Spring Compressor and Special tool 8519 Adapter,
compress the valve spring.
NOTE: It may be necessary to tap the top of the
valve spring to loosen the spring retainers locks
enough to be removed.
4. Remove the two spring retainer lock halves.
NOTE: the valve spring is under tension use care when releasing the valve spring compressor.
5. Remove the valve spring compressor.
6. Remove the spring retainer, and the spring.
NOTE: Check for sharp edges on the keeper grooves. Remove any burrs from the valve stem before remov-
ing the valve from the cylinder head.
7. Remove the valve from the cylinder head.
NOTE: The valve stem seals are common between intake and exhaust.
8. Remove the valve stem seal. Mark the valve for proper installation.
TESTING VALVE SPRINGS
NOTE: Whenever the valves are removed from the
cylinder head it is recommended that the valve
springs be inspected and tested for reuse.
Inspect the valve springs for physical signs of wear or
damage. Turn table of tool C-647 (1) until surface is in
line with the 40.12 mm (1.579 in.) mark on the
threaded stud and the zero mark on the front. Place
spring over the stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until a
Ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by two. This will give the
spring load at test length. Fractional measurements
are indicated on the table for finer adjustments. Refer
to Specifications Section to obtain specified height and
allowable tensions. Replace any springs that do not
meet specifications.
KJ
ENGINE - 3.7L
9 - 1507
INSTALLATION
1. coat the valve stem with clean engine oil and insert
it into the cylinder head.
2. Install the valve stem seal. make sure the seal is
fully seated and that the garter spring at the top of
the seal is intact.
3. Install the spring and the spring retainer.
4. Using the valve spring compressor, compress the
spring and install the two valve spring retainer
halves.
5. Release the valve spring compressor and make
sure the two spring retainer halves and the spring
retainer are fully seated.
6. lubricate the camshaft journal with clean engine oil
then Position the camshaft (with the sprocket dowel
on the left camshaft at 11 o’clock and the right
camshaft at 12 o’clock), then position the camshaft
bearing caps.
7. Install the camshaft bearing cap retaining bolts.
Tighten the bolts 9-13 N·m (100 in. lbs.) in 1/2 turn
increments in the sequence shown .
8. Position the hydraulic lash adjusters and rocker
arms (Refer to 9 - ENGINE/CYLINDER HEAD/
ROCKER
ARM
/
ADJUSTER
ASSY
-
INSTALLATION).
9 - 1508
ENGINE - 3.7L
KJ
ROCKER ARM - VALVE
DESCRIPTION
The rocker arms are steel stampings with an integral roller bearing. The rocker arms incorporate a 0.5 mm oil hole
in the lash adjuster socket for roller and camshaft lubrication.
REMOVAL
NOTE: Disconnect the battery negative cable to
prevent accidental starter engagement.
1. Remove the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER
HEAD/CYLINDER
HEAD
COVER(S) - REMOVAL).
2. For rocker arm removal on cylinder No. 4, Rotate
the crankshaft until cylinder No. 1 is at BDC intake
stroke.
3. For rocker arm removal on cylinder No. 1, Rotate
the crankshaft until cylinder No. 1 is at BDC com-
bustion stroke.
4. For rocker arm removal on cylinders No. 3 and No.
5, Rotate the crankshaft until cylinder No. 1 is at
TDC exhaust stroke.
5. For rocker arm removal on cylinders No. 2 and No.
6, Rotate the crankshaft until cylinder No. 1 is at
TDC ignition stroke.
6. Using special tool 8516 Rocker Arm Remover (2) ,
press downward on the valve spring, remove
rocker arm.
INSTALLATION
CAUTION: Make sure the rocker arms are installed
with the concave pocket over the lash adjusters.
Failure to do so may cause severe damage to the
rocker arms and/or lash adjusters.
NOTE: Coat the rocker arms with clean engine oil
prior to installation.
1. For rocker arm installation on cylinders No. 4,
Rotate the crankshaft until cylinder No. 1 is at BDC
intake stroke.
2. For rocker arm installation on cylinder No. 1,
Rotate the crankshaft until cylinder No. 1 is at BDC
combustion stroke.
3. For rocker arm installation on cylinders No. 3 and
No. 5, Rotate the crankshaft until cylinder No. 1 is
at TDC exhaust stroke.
4. For rocker arm installation on cylinders No. 2 and
No. 6, Rotate the crankshaft until cylinder No. 1 is
at TDC ignition stroke.
5. Using special tool 8516 (2) press downward on the
valve spring, install rocker arm.
KJ
ENGINE - 3.7L
9 - 1509
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