1998 HONDA CIVIC exhaust

Cylinder Head
lllustrated Index (cont'dl
VALVE KEEPERS
SPRING RETAINER
INTAKE VALVE
VTEC SOLENOIDVALVE FILTEBReplace.
OIL CONTROLORIFICEClean.
INTAKE VALVE SEALReplace.VALVE SPRINGSEAT
INTAKE VAI.VEGUIOE
CAMSHAFTPULLEY
I
I
VALVE KEEPERS
SPRING RET
EXHAUST VALVESPRING
@
EXHAUST VALVESEALReplace.
8 x 1.25 mm37 N.m 13.8 kgt m,27 tbfitlApply engine oiltothe threads.
EXHAUSTVALVE
-vp
e,.io"o reassembring, crean at the parts in sorvent, dry them and appry rubricant to any contact parts.
D16Y8 engine:
LOST MOTIONASSEMgLY
ROCKER ARMASSEMBLYRemoval, page 6 30Inspection, page 6-34
5xl.0mm12 N.m {1.28.7 tbf.ft)
VALVE SPRINGSEATEXHAUSTVALVE O.RINGGUIDE Replace.Inspection, page 6 39Replacement, page 6 41Reaming, page 6 43
LOST MOTIONASSEMBLYHOLDER
INTAKE VALVEBemoval, page 6 38Installation, page 6 43
20 N.m 12.0 kgl.m, 14 tbf.ft)Apply engine oit to thethreads.
\
\
s9illl
CAMSHAFTInspection, page 6-36
OIL SEALBeplace.
CYLINDER HEADRemoval, page 6 27Warpage, page 6-40Valve seat reconditioning,page 6 40Installation, page 6-45
6x1.0mm12 N.m (1.2 kgt.m,8.7 lbf.ftlApply engine oil to thethreads,

13. Remove the upper radiator hose' heater hose and
water bYPass hose
WATEREYPASSHOSEUPPERRADIATORHOSE
14.
HEATERHOSE
Remove the engine wire harness connectors and
wire harness clamps from the cylinder head and the
intake manifold.
o Four fuel injector connectors
. Engine coolant temperature (ECT) sensor con-
nector
a
a
a
ECT switch connector
ECT gauge sending unit connector
Throttle position sensor connector
Manitold absolute pressure (MAP) sensor con-
nector
Primary heated oxygen sensor (primary HO2S)
connector
Secondary heated oxygen sensor (secondary
HO2S) connector (D16Y7 engine)
Exhaust gas recirculation (EGR) valve lift sensor
connector (D16Y5 engine)
. VTEC solenoid valve connector (Dl6Y5, D16Y8
engrnes)
. VTEC pressure switch connector (D16Y5. D16Y8
engrnes,
. ldle air control (lAC) valve connector
15.Remove the spark plug caps and distributor from
the cylinder head.
Remove the uPPer bracket.
NOTE:
. Use a jack to support the engine before the
upper bracket is removed.
. Make sure to place a cushion between the oil
pan and the jack.
12 x 1.25 mm
74 N.m {7.5 kgf m.
sil lbl.ftl
UPPERBRACKET
'17. Remove the cylinder head cover'
CYLINDERHEAD COVER
(cont'd)
6-29

Cylinder HeadRocker Arms
18.
19.
21.
22.
Removal (cont'd)
Remove the timing belt {see page 6-19).
Remove the camshaft pulley and back cover,
CAMSHAFTPULLEYClean when installing.
6x1.0mm8 x 1.25 mm37 N.m (3.8 kgf.m,21 tbtlrlApply engine oilto thebolt threads.
Remove the exhaust manifold {see pages 9-6 and 9_7).
Remove the intake manifold (see pages 9-2 thru 4).
Remove the cylinder head bolts, then remove thecylinder head.
CAUTION: To pr€vent warpage, unsclew lhe bohsin sequonce 1/3 turn at a time; rgpeat tho sequenceuntil all bolts are loosened.
CYLINDER HEAD BOLTS LOOSENING SEOUENGE:
6-30
Removal
1. Loosen the adjusting screws.
2. Unscrew the camshaft holder bolts, then,removethe rocker arm assembly.
NOTE:
a Unscrew the camshaft holder bolts two turns at at,me, in a crisscross pattern, to prevent damao_ing the valves or rocker arm assembly.. When removing the rocker arm assembly, do notremove the camshaft holder bolts. The bolts willkeep the camshaft holders, the springs and therocker arms on the shaft.
CAMSHAFT HOLDER BOLTS LOOSENINGSEOUENCE:
\(
ADJUSTING SCREWS

Rocker Arms
Disassembly/Reassembly (cont'dl
NOTE:
. ldentify pans as they are removed to ensure reinstallation in original locations.. Inspect rocker shafts and rocker arms (see page 6-34).. Rocker arms must be installed in the same position if reused.t when removing or installing the rockerarm assembly, do not remove the camshaft holder bolts. The boltswill keeptheholders, springs and rocker arms on the shaft.
I erior to reassembring, crean a

the parts in sorvent, dry them and appry rubricant to any contact points.
D16Y5 engine:
ROCKER ARMS
TIMING PLATERUBBER BANO
(\
-]-
-P'g,rpt+.t't ll
\--,?|, -\2i lNo.5 CAMSHAFT _ lHOLDER l
No. 4 CAMSHAFTHOLDERNo. 3 CAMSHAFIHOLDERNo.2HOLDER
ra
I
EXHAUST ROCKERARM B{,1 plac€s)
EXHAUST ROCKEE SHAFT
Letter "A" is slamped
II{TAKE ROCKER SHAFT
!-r I
?h'ffi*ffi'
/^ ---IOCKER SHAFT
Letter "8" is stamped
6-32

D16Y8 engine:
No. 5 CAMSHAFTHOLDER
ARM B
ROCKER ARMS
No. 4 CAMSHAFTHOLOER
No. 3 CAMSHAFTHOLDER
No. 2 CAMSHAFTHOLDER
No. 'l CAMSHAFTHOLDER
R(rcKER SHAFTSPRING
Letter "B" is stampedLetter "A" is stamped
L
INTAKE SOCKER SHAFT
ROCKER SI{AFT
COLLARNUBBER BANDCOLLAR
EXHAUST ROCKER SHAFT
6-33

Rocker Arms and Shafts
Clearance Inspection
Measure both the intake rocker shaft and exhaust rocker
shaft.
1. Measure the diameter of the shaft at the first rocker
locatron.
2. Zero the gauge to the shaft diameter'
I
3. Measure the inside diameter of the rocker arm and
check for an out of-round condition.
Rockel Arm-to-Shaft Clearance
Standard (Newl:
lntake: 0.017 - 0.050 mm
{0.0007 - 0.0020 inl
Exhaust: 0.018 - 0.054 mm
(0 0007 - 0 0021 in)
Service Limit:0.08 mm {0.003 inl
Repeat these measurements on all the rockers.
- lf the clearance is over the service limit, replace the
rocker shaft and all over tolerance rocker arms.
6-35

6, Remove the camshaft holders. then measure the
widest ponion of the plastigage on each journal.
Camshaft-to-Holder Oil Clearance:
Standard lNew):0.050 - 0.08!t mm
{0.002 - 0.004 in}
Service Limit : 0.15 mm {0.006 in)
lf the camshaft-to-holder oil clearance is out ot 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 inl max.
Service Limit: 0.04 mm {0.(X)2 in)
-7.
Rotate camshattwhile measuring.
L
- 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
O16Y/ engine35.299 (1.3897)37.281 (1.4678)
D16Y5
engrne
PRI38.427 11.5129138.784 (1.5269)
SEC32.193 (1.2674)
D l6Y8
engrne
PRI36.77811.44791
38.008 (1.4964)MID38.274 (1.5068)
sEu37.065 (1.4592)
8. Check the cam lobe height wear.
Cam lobe height standard (New)
t/g a* rN Ex
- D16Y5 engine
PRI; Primary cam lobe, SEC: Secondary cam lobe
MtD: Mid cam lobe. T/B: Timing belt
lN: Intake, EX: Exhaust
PRIsEcMIDSEC
rts
- Dl6YE ongine
Unit mm (in)
Check this area {or wear.
6-37

Valve Guides
lntake Valve Dimensions
A Standsrd lNewl: 29.9 - 30.1 mm
B Standard (New):
C Standald {Newl:
C Service Limit:
D Standard (New):
D Service Limit:
11.18 - 1.19 inl
117.42 - 117.72 mm
(4.523 - 4.635 inl
5.'18 - 5.49 mm
{0.2r57 - 0.2r61 in)
5.,[5 mm (0.21,16 in]
0.85 - 1.15 mm
(0.033 - 0.0'15 in)
0.65 mm (0.026 in)
Exhaust Valve Dimensions
A Standard lNew): 25.9 - 26.1 mm
B Standard {Newl:
C Standard {New):
C Service Limit:
D Standard {New):
D Service Limit:
(1.02 - 1.03 in)
114.60 - 114.90 mm
11.512 - 4.521in1
5.i[5 - 5.46 mm
10.21lt6 - 0.2150 inl
5.,12 mm 10.213'l in)
1.05 - 1.35 mm
{0.041 - 0.053 in)
0.95 mm {0.037 in}
Valve Movement
Measure the guide-to-stem clearance with a dial indi-
cator while rocking the stem in the direction of normal
thrust (wobble method).
lniake Valve Stem-to-Guide Clearance:
St8ndard lNew): 0.04 - 0.10 mm
10.002 - 0.004 in)
Service Limit: 0.16 mm 10.006 in)
Exhaust Valvs Stem-to-Guide Glearance:
Standard {New}: 0.10 - 0.16 mm
10.004 - 0.006 in)
Sorvice Limit 0.22 mm (0.009 in)
O/'-_)
. lf the measurement exceeds the service limit,
recheck using a new valve.
. lf the measurement is now within the service
limit, reassemble using a 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, measured 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 be-
tween the largest guide measurement and the
smallest stem measurement should not exceed the
service limit.
lntake Valve Stgm-to-Guidg clearance:
Standard {Newl: 0.02 - 0.05 mm
{0.001 - 0.002 in)
Ssrvico Limit 0.08 mm (0.003 in)
Exhaust Valvo Stem-to-Guide Clearance:
Standard {New): 0.05 - 0.OB mm
{0.002 - 0.003 in)
S€rvice Limit 0.11 mm (o'Ooil in)
Valve extended 10 mm out from seat.
6-39