cylinder head HONDA CIVIC 1996 6.G Service Manual

Removal
Engine removal is not required for this procedure.
!@@ Make sure jacks and safety stands are placed
properly and hoist brackels are attached to correst posi-
tion on the engine,
CAUTION:
o Use fender covers to avoid damaging painted sur-
faces.
To avoid damage, unplug the wiling connectors
carelully while holding the connector portion.
To avoid damaging the cylinder head, wait until the
engine coolant temperature drops below 100"F {38'Cl
before loosening the retaining bolt.
NOTE:
. Unspecified items are common.
. Mark all wiring and hoses to avoid misconnection.
AIso, be sure that they do not contact other wiring or
hoses or interfere with other parts.
o Inspect the timing belt before removing the cylinder
n eao.
. Turn the crankshaft pulley so that the No. 1 piston is
at top dead center (see page 6-64).
1. Disconnect the negative terminal from the battery.
Drain the engine coolant {see page 10-7).
. Remove the radiator cap to speed draining.
Remove the strut brace (see page 5-2).
Remove the intake air duct and air cleaner housing
(see page 5-3).
Remove the adjusting bolt and mounting bolt, then
remove the power steering (P/S) pump belt and pump
(see page 5 5).
2.
3.
4.
\
ADJUSTING
6. Loosen the idler pulley bracket bolt and adjusting
bolt, then remove the air conditioning (A/C) com-
pressor belt.
IDLER PULLEY BRACKETBOLT10 x 1.25 mm44 N.m {4.5 kg,l.m, 33 lbt.ft}
7. Loosen the mounting nut and lock bolt, then remove
the alternator belt.
LOCK BOLT8 x 1.25 mm24 N.m {2.4 kgf.m,17 tbtftl
ALTERNATORBELT10 x 1.25 mm,l,l N.m {4.5 kgf.m,33 tbf.ft,
(cont'd)
6-67

Cylinder Head
Removal (cont'd)
8. Remove the P/S pump lower bracket.
8 x 1.25 mm24 N.m 12.4 kgf.m,17 tbtftl
9.
T SHIELD
10.
P/S PUMP LOWERBRACKET10 x 1.25 mm44 N.m {4.5 kgf.m,33 tbf.frl
Relieve fuel pressure (see section l1).
@ Do not smok6 while working on fuel
system, keep open flam€ or spark away lrom work
ar€a, Drain fuelonly into an approved cortain€r.
Remove the evaporative emission (EVAP) control
canister hose, fuel feed hose and breather hose.
BANJO BOLT33 N.m (3.4 kgl.m.25 lbf.ftl
BREATHERHOSE
WASHERS
6-68
\.
11. Remove the brake booster vacuum hose, fuel return
hose and vacuum hose (see page 5 4).
12. Remove the water bypass hose and positive crankcase
ventilation (PCV) hose.
WATER BYPASSHOSEWATER EYPASSHOSE
Remove the throttle cable and throttle control cable
by loosening the locknut, then slip the cable end out
of the throftle linkage.
NOTE;
. Take care not to bend the cables when removing
them. Always replace any kinked cable with a new
one.
. Adjust the throttle cable when installing (see sec-
tion I I ),. Adjust the throttle control cable when installing(see section 14).
CONTROLCABLE
1a
PCV HOSE

WATER BYPASS
HOSE
14. Remove the upper radiator hose, heater hose and
water bvpass hose.
HEATER
Remove the engine wire harness connectors and wlre
harness clamps from the cylinder head and the intake
manifold.
Four fuel injector connector
Engine coolant temperature (ECT) sensor connec-
tor
ECT gauge sending unit connector
ECT switch connector
ldle air control (lAC) valve connector
Manifold absolute pressure (MAP) sensor connec-
tor
Throttle position sensor connector
Primary Heated oxygen sensor (Primary HO2S)
connecror
VTEC solenoid valve connector
15.
a
a
a
a
a
\
16.
17.
Remove the spark plug caps and distributor form
the cylinder head.
Remove the upper bracket.
NOTE:
. Use a jack to support the engine before removing
the upp€r bracket is removed.
. Place a cushion between the oil panandthejack.
12 x 1.25 fin74 N.m 17.5 kgtm,
UPPER BRACKET
18. Remove the cylinder head cover.
{cont'd)
6-69

Cylinder Head
19.
20.
Removal (cont'dl
Remove the timing belt {see page 6-62).
Remove the back cover and camshaft pulleys.
BACK COVER
56 N.m (5.7 kgf m,
41 tbt.f06xl.0mm9.8 N,m (1.0 kgf.m, 7.2 lbf.ft)
21, Remove the exhaust manifold (see page 9-8).
22. Remove the intake manifold (see page g-5).
23. Loosen the adjusting screws.
INTAKE
No.4 No.3 No.2 No. 1
6-70
24. Remove the camshaft holder plates, camshaft hold-ers and camshafts.
CAMSHAFTHOLDER PLATE
Remove the cylinder head bolts, then remove the
cylinder head.
CAUTION: To prevsnt warpage. unscrew the bolts
in sequonc€ 1/3 turn at a tim€; lepeat lh6 sequence
until all bolts aro loosened.
CYLINDER HEAD BOLTS LOOSENING SEOUENCE:
CYLINDER HEADPLUGReplace. t
\1
\€\i
b4CAMSIIAFTS -

Rocker Arms and Lost Motion Assemblies
Inspection
NOTE: When reassembling the primary rocker arm, care-
fully apply air pressure to the oil passage of the rocker
arm.
PRIMARY ROCKER ARM
MID ROCKER ARM
Inspect each rocker arm piston. Push it manually
- lf it does not move smoothly. replace the rocker
arm assemDly.
1.
SECONDARY
Check prston movement
NOTE:
. Apply oilto the pistons when reassembling.
. Bundle the rocker arms with a rubber band to
keep them together as a set.
PISTONS
PRIMARY
\
6-73
2. Remove the lost motion assembly from the cylinder
head and inspect it. Test it by pushing the plunger
with your finger,
- lf the lost motion assembly does not move
smoothly, replace it.
LOST MOTION ASSEMBLY
Push
I

Camshafts
Inspection
NOTE:
. Do not rotate the camshaft during inspection.
. Removg the rocker arms and rocker shafts.
'L Put the camshafts and camshaft holders on the cylin-
der head. and then tighten the bolts to the specified
torque.
Specified Torque:
O -@: 8 mm botts 27 N.m {2.8 kgf.m,20 lbt'ft)
Apply engine oil to the threads,
O - @: 6 mm bolts 9.8 N.m (1.0 kgf m, 7.2 lbf'ft)
Seat the camshaft by pushing it toward the distribu-
tor end of the cylinder head.
Zero the dial indicator against the end of the distrib-
utor drive. then push the camshaft back and fonh
and read the end play.
Camshaft End Play:
Standard {New}: 0.05 - 0.15 mm
{0.002 - 0.006 inl
Service limil: 0.5 mm (0.02 in)
ooooooo
ooooo
\-
4.Remove the bolts. then remove the camshaft hold-
ers from the cylinder head.
- Lift the camshaft out of the cylinder head, wipe
clean, then inspect the lift ramps. Replace the
camshaft if lobes are pitted, scored, or excessively
- Clean the camshaft bearing surfaces in the cylin
der head, then set the camshaft back in place,
- Insert a plastigage strip across each iournal.
Put the camshaft on the cylinder head. then install
the camshaft holders, and then tighten the bolts to
the specified torque as shown in the left column on
this page.
Remove the camshaft holders, then measure the
widest portion of the plastigage on each journal.
Camshaft -to-Hold€1 Oil Clearsnce:
Standard {Newl: 0.050 - 0.089 mm
{0.002 - 0.004 inl
S6rvice Limit: 0.15 mm 10,006 inl
(cont'd)
6-75
PLASTIGAGE STRIP

Gamshafts
Inspection (cont'dl
7. lf the camshaft-to-holder oil clearance is out of tol-
erance:
- And the camshaft has already been replaced, you
must replace the cylinder head.- lf the camshaft has not been replaced, first check
the total runout with the camshaft supported on
V-blocks.
Camshaft Total Runout:
Standard (New): 0.03 mm {0.001 in} max.
Service Limit: 0.04 mm (0.002 inl
- lf the total runout of the camshaft is within toler,
ance, replace the cylinder head.- lf the total runout is out of tolerance. replace the
camshaft and recheck the camshaft to,holder oil
clearance. lf the oil clearance is still out of toler-
ance, replace the cylinder head.
INTAKEEXHAUST
PRIMARY33.088 mm
{1.3027 in)
32.785 mm
(1.2907 inl
MID36.267 mm(1.4278 in)
35.720 mm
{1.4063 in)
SECONDARY34.978 mm(1.3771 inl
3i1.691 mm(1.3658 in)
8. Check the cam lobe height.
Cam lobe height standard (New):
Cam Position
I
INTAKE
MID
EXHAUST
SEC MID PRI
TIB
T/B: TIMING BELTPRI: PRIMARYMID: MID
Check thrs area lor wear.

Valve Seats
Reconditioning
1. Renew the valve seats in the cylinder
valve seat cutter.
NOTE: lf any guides are worn (see
replace them (see page 6-80) before
valve seats,
head with a
page 6-79),
cutting the
Carefully cut a 45o seat, removing only enough mate-
rial to ensure a smooth and concentric seat.
Bevel the upper edge of the seat with the 30" cutterand the lower edge of the seat with the 60. cutter.Check width of seat and adjust accordingly,
Make one more very light pass with the 45" cutter toremove any possible burrs caused bv the other cut-
ters.
Valve Seat Width:
Standard (Newl: 1.25 - 1.55 mm {0.0't9 - 0.061 in)Service Limii: 2.0 mm 10,08 inl
Sear Widrh
6-78
5. After resufacing the seat. inspect for even valveseating: Apply Prussian Blue Compound to thevalve face, and insert the valve in its original loca-tion in the head. then lift it and snap it closedagainst the seat several times.
PRUSSIAN BLUE COMPOUND
The actual valve seating surface, as shown by theblue compound, should be centered on the seat.. lf it is too high (closer to the valve stem), you mustmake a second cut with the 60. cutter to move itdown, then one more cut with the 45. cutter torestore seat width.
. lf it is too low (closer to the valve edge), you must
make a second cut with the 30. cutter to move itup. then one more cut with the 45. cutter to restoreseat width.
NOTE: The final cut should always be made withthe 45" cutter,
7. Insen the intake and exhaust valves in the head and
measure valve stem installed heioht.
Intaka Valve Stem Installed Height:
Standsrd lNaw): 37.465 - 37.935 mm(1./P50 - r.4935 inl
Sorvice Limit: 38.185 mm 0.5033 in)
Exhau3t Valv€ Stem Installed Height:
Standard (New): 37.165 - 37.6i|5 mm(1.46:t2 - 1.i1817 inl
Servico Limit 37.885 (1.4915 inl
lf valve stem installed height is over the service limit,replace the valve and recheck. lf it is still over the ser-vice limit, replace the cylinder head; the valve seat inthe h6ad is too deep.
(

Cylinder HeadValve Guides
Warpage
NOTE: lf camshaft-to-holder oil clearances (see page 475)
are not within specification, the head cannot be resurfaced.
lf camshaft-to-holder oil clearances are within specifica-
tions, check the head for warPage.
. lf warpage is less than 0.05 mm (0.002 in) cylinder
head resurfacing is not required.
. lf warpage is between 0.05 mm (0.002 in) and 0 2 mm
(0.008 in), resurface cylinder head
. Maximum resurface limit is 0.2 mm (0.008 in) based
on a height of 142 mm (5.59 in).
PRECISION STRAIGHT EDGE
Measure along edges, and three ways across center'
Cylinder Head Height:
Standard lNewl: 1i11.95 - 142.05 mm
15.589 - 5.593 in)
Valve Movement
Measure the guide-to-stem clearance with a dial indica-
tor while rocking the stem in the direction of normal
thrust (wobble method).
lntake Valve Stem-to-Guide Cl6arance:
Standard (Newl: 0.05 - 0.11 mm
(0.0020 - 0.0043 inl
Service Limit: 0.15 mm {0.0059 inl
Exhaust Valve Stem-to-Guide Clealance:
Standard lNewl: 0.10 - 0.16 mm
(0.0039 - 0.0063 inl
Service Limit: 0.24 {0.0094 in)
Valve extended 10 mm out from seat.
lf the measurement exceeds the service limit, recheck
using a new valve.
lf the measurement is now within the service limit.
reassemble using the new valve
lf the measurement still exceeds the limit. recheck using
the alternate method below. then replace the valve and
guide, if necessary.
NOTE: An alternate method of checking guide to stem
clearance is to subtract the o.D. of the valve stem, mea-
sured with a micrometer, from the l.D. of the valve guide,
measured with an inside micrometer or ball gauge.
Take the measurements in three places along the valve
stem and three places inside the valve guide.
The difference between the largest guide measurement
and the smallest stem measurement should not exceed
the service limit.
lntake Valv€ Stem-to-Guide Clsarance:
Standard lNswl: 0.025 - 0.055 mm
10.0010 - 0.0022 inl
service Limit: 0.08 mm (0.003 in)
Exhaust Valve Stem-to Guide Cl€arance:
Standard {Newl: 0.050 - 0.080 mm
{0.0020 - 0.0031 inl
Service Limit 0.ll mm (0.004 in)
6-79

t
Valve Guides
Replacement
1. As illustrated below, use a commerciallv available
air-impact valve guide driver attachment modified
to fit the diameter of the valve guides. ln most
cases, the same procedure can be done using the
sDecial tool and a conventional hammer.
COMMERCIALLY AVAILABLEVALVE GUIDE DRIVER
87 mm -L- sz mm(3.43 inl I tz.zr int
rE-tt
10.8 mm10.42 inl
olVALVE GUIOE DRIVER,5.5 mm077,P - 0010100
Select the proper replacement guides and chill
them in the freezer section of a refrigerator for
about an hour.
Use a hot plate or oven to evenly heat the cylinder
head to 300"F (150"C). Monitor the temperature with
a cooking thermometer.
CAUTION:
. Do not use a torch; it may warp tho head.. Do not get tho head hotter than 300"F {150"C};excesgive heat may loosen thg valve seats.. To avoid burns. use haaw gloves whon handling
the heatod cylinder head.
6-80
Working from the camshaft side, use the driver and
an air hammer to drive the guide about 2 mm (0.1 in)
towards the combustion chamber. This will knock off
some ofthe carbon and make removaleasier.
CAUTION:
. Always wsar safety goggles or a face shield whsn
driving valve guides.
. Hold the air hammer dir€ctly in line with the
valve guide to prevont damaging thg dtiver.
Turn the head over and drive the guide out toward
the camshaft side of the head.
VALVE GUIOE DRIVER,5.5 mm077{2 - 0010100
lf a valve guide still won't move. drill it out with a8.0 mm (5/16 in) bit, then try again.
CAUTION: Drill guides only in extreme cases; you
could damago the cylinder head if ths guide br6aks.
Remove the new guide(s) from the freezer, one at a
time, as vou need them.
-:^-,65i^q
NNSp-<