NISSAN PRIMERA 1999 Electronic Repair Manual
Page 1681 of 2267
Removal
1. Drain coolant and disconnect front exhaust pipe from manifold.
2. Remove water hoses, air duct and intake manifold.
3. Remove heat shield and exhaust manifold.
4. Remove rocker cover and injection tubes.
5. Remove both timing belts.
Set No. 1 cylinder at TDC on its compression stroke. Refer to
ªTIMING BELTº (EM-134).
After timing belts have been removed, do not rotate crankshaft
and/or camshaft separately as valves will hit piston heads.
6. Remove cylinder head bolts in numerical order as shown in the
figure.
Disassembly
1. Remove front camshaft sprocket plate, front and rear sprock-
ets using special service tool or a suitable tool, and front back
cover.
2. Remove camshaft brackets in order from outside to inside.
ILoosen camshaft bracket nuts in two or three stages.
3. Remove camshaft and oil seals.
4. Remove valve lifters.
For valve lifter
IAttach tags to valve lifters for identification.
5. Remove valve component parts using special service tool or a
suitable tool.
IKeep each valve and its components together and mark
them so they can be reassembled in their original posi-
tions.
6. Remove valve oil seals using special tool.
SEM373D Drain plug
(cylinder block)
SEM682D
SEM864
SEM716B
SEM745BA
CYLINDER HEADCD20T
Removal
EM-141
Page 1682 of 2267
Inspection
CYLINDER HEAD DISTORTION
1. Visually check for cracks and deformation.
2. Check cylinder head for distortion.
Head surface flatness:
Less than 0.1 mm (0.004 in)
If beyond the specified limit, replace or resurface cylinder
head.
Resurfacing limit:
The resurfacing limit of the cylinder head is related to the
amount of resurfacing of the cylinder block.
When:
ªAº is the amount of resurfacing needed for the cylinder head
and ªBº is the amount of resurfacing needed for the cylinder
block, the maximum limit is determined by
A + B = 0.1 mm (0.004 in)
After resurfacing cylinder head, check that camshaft rotates freely
by hand. If resistance is felt, the cylinder head must be replaced.
Nominal height of cylinder head:
137.9 - 138.1 mm (5.429 - 5.437 in)
VALVE GUIDE CLEARANCE
1. Measure deflection across the cylinder head as illustrated.
Valve deflection limit (dial gauge reading):
0.1 mm (0.004 in)
2. If exceeding the limit, check valve-to-guide clearance.
a) Measure valve stem diameter and valve guide inner diameter
as illustrated.
b) Check that clearance is within the specification.
Valve stem to valve guide clearance limit:
0.1 mm (0.004 in)
c) If exceeding the limit, replace valve or valve guide.
VALVE GUIDE REPLACEMENT
1. Heat cylinder head in oil to 150 to 160ÉC (302 to 320ÉF).
2. Drive out valve guide using a press or hammer and a suitable
tool.
SEM595A Warpage of surface:
Less than 0.1 mm (0.004 in)
SEM870
SEM244D Micrometer
To p
Center
Bottom
Valve guide Valve
SEM871
CYLINDER HEADCD20T
Inspection
EM-142
Page 1683 of 2267
3. Ream cylinder head valve guide bore.
Reaming bore (service part):
11.185 - 11.196 mm (0.4404 - 0.4408 in)
4. Heat cylinder head to 150 to 160ÉC (302 to 320ÉF) and press
service valve guide onto cylinder head.
5. Ream valve guide.
Final size:
7.000 - 7.015 mm (0.2756 - 0.2762 in)
VALVE SEATS
1. Check valve and valve seat for contact.
Coat the valve face with prussian red lead. If contact is wrong,
correct valve seat. If the valve red lead appears 360É around
face, the valve stem and face are concentric. If not, repair or
replace valve.
2. Check valve seats for pitting at contact surface. Resurface or
replace if excessively worn.
Correct valve seat surface.
When repairing valve seat, check valve and valve guide for
wear beforehand. If worn, replace them. Then correct valve
seat.
VALVE SEAT REPLACEMENT
1. Bore out old seat until it collapses.
Set machine depth stop so that boring cannot contact bottom
face of seat recess in cylinder head.
2. Ream the cylinder head recess.
Reaming bore for service valve seat
[Oversize 0.5 mm (0.020 in)]:
Intake 41.432 - 41.454 mm (1.6312 - 1.6320 in)
Exhaust 35.432 - 35.454 mm (1.3950 - 1.3958 in)
Use the valve guide center for reaming to ensure valve seat
will have the correct fit.
.SEM245D
SEM246DA 10.3 mm
(0.406 in)
SEM722BA
SEM795A Recess diameter
CYLINDER HEADCD20T
Inspection (Cont'd)
EM-143
Page 1684 of 2267
3. Heat cylinder head to a temperature of 150 to 160ÉC (302 to
320ÉF) and press fit seat until it seats on the bottom.
4. Install valve seats.
When replacing valve seat, valve should be replaced as well.
5. Cut or grind valve seat using a suitable tool at the specified
dimensions as shown in SDS (EM-198).
The cutting should be done with both hands to obtain a uni-
form and concentric finish.
6. Apply a small amount of fine grinding compound to the valve's
contacting face and put the valve into its guide.
Lap valve against its seat until proper valve seating is
obtained.
7. Check valve seating condition.
VALVE DIMENSIONS
1. Check dimensions of each valve. For dimensions, refer to SDS
(EM-197).
2. Correct or replace any valve that is faulty.
SEM876
SEM877
SEM635AA W: Refer to SDS.
SEM188A T (Margin thickness)
CYLINDER HEADCD20T
Inspection (Cont'd)
EM-144
Page 1685 of 2267
3. Valve face or valve stem end surface should be refaced by
using a valve grinder.
When valve head has been worn down to 0.5 mm (0.020 in) in
margin thickness, replace the valve.
Grinding allowance for valve stem tip is 0.5 mm (0.020 in) or
less.
VALVE SPRING SQUARENESS
Check valve spring for squareness using a steel square and flat
surface plate.
If spring is out of square ªSº more than specified limit, replace with
new one.
Out-of-square:
Outer
Less than 1.8 mm (0.071 in) Ð Intake Ð
Less than 2.2 mm (0.087 in) Ð Exhaust Ð
Inner
Less than 1.6 mm (0.063 in) Ð Intake Ð
Less than 1.8 mm (0.071 in) Ð Exhaust Ð
VALVE SPRING PRESSURE LOAD
Measure the free length and the tension of each spring. If the
measured value exceeds the specified limit, replace spring. Refer
to SDS (EM-197).
VALVE LIFTER
1. Check contact and sliding surfaces for wear or scratches.
E M 111
SEM333
EM113
SEM723B
CYLINDER HEADCD20T
Inspection (Cont'd)
EM-145
Page 1686 of 2267
2. Check diameter of valve lifters.
Outer diameter:
34.959 - 34.975 mm (1.3763 - 1.3770 in)
3. Check valve lifter guide bore.
Bore diameter
34.998 - 35.018 mm (1.3779 - 1.3787 in)
Standard clearance
0.023 - 0.059 mm (0.0009 - 0.0023 in)
COMBUSTION CHAMBER REPLACEMENT
Usually combustion chambers should not be removed.
However, if they show cracks or extensive damage, they
should be replaced.
1. Remove glow plug connecting plate, glow plugs and injection
nozzle.
2. Heat cylinder head in oil to between 150 and 160ÉC (302 and
320ÉF).
3. Remove combustion chamber so that cylinder head will not be
damaged.
Be careful not to scratch inside of nozzle hole.
4. Install combustion chamber.
a. Heat cylinder head 150 to 160ÉC (302 to 320ÉF) in oil.
b. Align combustion chamber knock pin with cylinder head notch,
and install it into cylinder head using a plastic-tip hammer.
SEM724B
SEM725B
SEM720B
.SEM721B
CYLINDER HEADCD20T
Inspection (Cont'd)
EM-146
Page 1687 of 2267
CAMSHAFT VISUAL CHECK
Check camshaft for scratches, seizure and wear.
CAMSHAFT END PLAY
1. Install camshaft in cylinder head.
2. Tighten bracket bolts to the specified torque.
3. Measure camshaft end play.
Camshaft end play: Standard
0.115 - 0.188 mm (0.0045 - 0.0074 in)
CAMSHAFT RUNOUT
1. Measure camshaft runout at the center journal.
Runout (Total indicator reading):
Limit 0.05 mm (0.0020 in)
2. If it exceeds the limit, replace camshaft.
CAMSHAFT CAM HEIGHT
1. Measure camshaft cam height.
Cam height: Standard
Unit: mm (in)
Intake 48.70 - 48.75 (1.9173 - 1.9193)
Exhaust 49.15 - 49.20 (1.9350 - 1.9370)
2. If wear is beyond the limit, replace camshaft.
CAMSHAFT JOURNAL CLEARANCE
Using micrometer
1. Measure the inner diameter of camshaft bearings.
Standard inner diameter:
30.000 - 30.021 mm (1.1811 - 1.1819 in)
Tighten bracket bolts to the specified torque.
2. Measure the outer diameter of camshaft journals.
Standard outer diameter:
29.935 - 29.955 mm (1.1785 - 1.1793 in)
If clearance exceeds the limit, replace camshaft and/or cylinder
head.
Standard clearance:
0.045 - 0.086 mm (0.0018 - 0.0034 in)
Limit: 0.1 mm (0.004 in)
SEM726B
SEM155
.SEM730B
.SEM727B
SEM728B
CYLINDER HEADCD20T
Inspection (Cont'd)
EM-147
Page 1688 of 2267
Using plastigage
1. Wipe off oil from camshaft journal bracket caps and brackets.
2. Install camshaft in journal bracket caps and put plastigage on
each camshaft journal.
3. Install cam bracket caps and tighten cam bracket cap nuts in
the correct order to the specified torque.
: 18 - 22 N´m (1.8 - 2.2 kg-m, 13 - 16 ft-lb)
4. Remove cam bracket caps and measure maximum width of
plastigage.
Camshaft bearing clearance:
Limit
0.1 mm (0.004 in)
5. If clearance appears to exceed the limit, replace camshaft or
cylinder head.
IWhich parts to be replaced should be decided upon after mea-
suring the diameters of the parts concerned.
Valve clearance
Checking
Check valve clearance while engine is warm and not running.
1. Remove rocker cover.
2. Set No. 1 cylinder at TDC on its compression stroke.
IAlign pointer with TDC mark on crankshaft pulley.
ICheck that valve lifters No.
p1andp2are loose and valve
lifters No.
p7andp8are tight.
If not, turn crankshaft one revolution (360É) and align as
described above.
3. Check valve clearances of valve lifter No.
p1,p2,p4and
p6.
SEM879
SEM880
SEM369F
SMA406A
CYLINDER HEADCD20T
Inspection (Cont'd)
EM-148
Page 1689 of 2267
IUsing a feeler gauge, measure clearance between valve lifter
and camshaft.
IRecord any valve clearance measurements which are out of
specification. They will be used later to determine the required
replacement adjusting shim.
Valve clearance for checking (Hot):
Intake
0.25 - 0.35 mm (0.010 - 0.014 in)
Exhaust
0.39 - 0.49 mm (0.015 - 0.019 in)
3. Turn crankshaft one revolution (360É) until No. 4 cylinder is at
TDC on its compression stroke.
4. Check valve clearances of valve lifter No.
p3,p5,p7and
p8.
IUse the same procedure as mentioned in step 3.
5. If all valve clearances are within specification, install the fol-
lowing parts:
IRocker cover
Adjusting
Adjust valve clearance while engine is cold.
1. Turn crankshaft. Position cam lobe upward on camshaft for
valve that must be adjusted.
2. Place Tool (A) around camshaft as shown in figure.
Before placing Tool (A), rotate notch toward center of cylinder
head. (See figure.) This will simplify shim removal later.
CAUTION:
Be careful not to damage cam surface with Tool (A).
3. Rotate Tool (A) (See figure.) so that valve lifter is pushed down.
4. Place Tool (B) between camshaft and valve lifter to retain valve
lifter.
CAUTION:
ITool (B) must be placed as close to camshaft bracket as
possible.
IBe careful not to damage cam surface with Tool (B).
5. Remove Tool (A).
SEM634F Feeler gauge
SMA406A
.SEM636F Face directly upwards.
Notch
.SEM637F Tool (B)
KV10115120
Tool (A)
KV10115110
CYLINDER HEADCD20T
Checking (Cont'd)
EM-149
Page 1690 of 2267
6. Remove adjusting shim using a small screwdriver and a mag-
netic finger.
7. Determine replacement adjusting shim size using the following
formula.
IUse a micrometer to determine thickness of removed shim.
ICalculate thickness of new adjusting shim so valve clearance
comes within specified values.
R = Thickness of removed shim
N = Thickness of new shim
M = Measured valve clearance
S = Standard valve clearance (neutral value for calculation)
Unit: mm (in)
HOTIntake 0.30 (0.012)
Exhaust 0.44 (0.017)
COLDIntake 0.25 (0.010)
Exhaust 0.38 (0.015)
Intake:
N=R+[MþS]
Exhaust:
N=R+[MþS]
Shims are available in 15 sizes from 2.20 mm (0.0866 in) to 2.90
mm (0.1142 in), in steps of 0.05 mm (0.0020 in).
ISelect the closest size shim to the calculated thickness.
Refer to chart in SDS, EM-198.
8. Install new shim using a suitable tool.
IInstall with the surface on which the thickness is stamped
facing down.
9. Place Tool (A) as explained in steps 2 and 3.
10. Remove Tool (B).
11. Remove Tool (A).
12. Recheck valve clearance.
Valve clearance:
Unit: mm (in)
For adjusting
Hot Cold* (reference data)
Intake0.25 - 0.35
(0.010 - 0.014)0.20 - 0.30
(0.008 - 0.012)
Exhaust0.39 - 0.49
(0.015 - 0.019)0.33 - 0.43
(0.013 - 0.017)
*: At a temperature of approximately 20ÉC (68ÉF)
Whenever valve clearances are adjusted to cold specifications, check that the
clearances satisfy hot specifications and adjust again if necessary.
SEM638F Small screwdriver
Magnetic finger
SEM145D
AEM236 Indicate
T
1= 2.800 mm
(0.1102 in)
Shim
CYLINDER HEADCD20T
Adjusting (Cont'd)
EM-150