CYLINDER HEAD DISASSEMBLY

⇐ ПредыдущаяСтр 9 из 19Следующая ⇒

Remove the valve spring cotters, retainers, springs and valves wi th the Valve Spring Compressor.

CAUTION

(11 GASK ET

(2) DOWE L PINS

NOTE

-.: 11

(1) VALVE SPRING COMPRESSOR

07757-0010000 OR 07957-3290001

Remove the valve stem seals and valve spring seats.

(1) VALVE STEM SEALS

(21 VALVE SPRI NG SEATS

Remove carbon deposits from the combustion chamber and clean off the head gasket surf aces.

N OTE

INSPE CTI ON

CYLIN D E R H EAD

Check the spark plug hole and valve areas for cracks.

Check the cylinder head for warpage with a strai!llt edge and feeler gauge as indicated.

SERVICE LIM IT: 0.10 mm (0.004 in)

INSP ECTI ON

VALVE SPR I N GS

Measu re the free length of the inner and outer valve springs.

SERVICE LIMITS:

I N NE R U NI: 35.58 mm (1.4008 in ) ( EX ): 43.32 mm (1.666 in)

OUTER U N J: 44.3 mm (1.744 in )

( EX): 44.29 mm (1.744 in)

R eplace th e springs i i they are shorter than the service limits.

VA LVE STEM-TO-GUIDE CLEAR ANCE

Inspect each valve for trueness,burning,scratches or abnormal nem wear.

Check valve movement in the guide and measure and record each va lve stem O.D.

SERVICE LIMITS:

IN: 5.45 mm (0.215 in) EX: 6.55 mm (0.258 in)

NOTE

Measure and record each valve guide 1.0.

SERVICE LIMIT :

IN: 5.56 mm (0.219 in)

EX: 6.65 mm (0.262 in)

Subtract each valve nem 0.0. from the correspond· ing guide 1.0. to obtain the stem to guide clearance.

SER VICE LIMITS :

IN: 0.10 mm (0.004 in) EX : 0.11 mm (0.004 in)

If the stem·to guide clearance exceeds the service limits, determine if a new guide with Handard dimensions (page 10·1) wou ld bring the clearance within tolerance. If so, replace any guides as neces sary and ream to fit.

If the stem·to-guide clearance exceeds the service limits with new guides. also replace the valves.

NOTE

VALVE GUIDE R EPLACEME N T

Heat the cylinder head to 100°C (212°F) w ith a

hot plate or oven.

CAUTION

Do n ot us e a rorch 1 0 he ar t h e cylinder head; ir may c au se "Vlfpf11g .

(1)

VALVE GUIDE REAMER

5.5 mm, 07984-2000000 (IN)

6.5 mm, 07984-6570100 (EX)

(1) VA LVE GUIDE REMOVER 5.5 mm, 07742-0010100 (IN) 6.6 mm, 07742-0010200 (EX)

Support the cylinder head and drive out the old guides from the combust ion chamber side of the cylinder head.

NOTE

I Avo i d damag i ng the cy l i nder head.

Drive new guides in from the rocker arm side of the cylinder head.

VA LVE GUIDE PROJECTION A BOVE

CYLINDER HEAD:

IN: 19.5 ± 0.1 mm (0.768 :t 0.004 in)

EX: 18.0 :t 0.1mm (0.719 :t 0.004 in)

Ream the new valve guides after installation. NOTE

Use cutting oil on the reamer during this operation.

It is important that the reamer always be

rotated in the cutting dlirection when it is inserted or removed.

Clean the head thoroughly after reaming the valve guides.

(1) VALVE GUIDE DRIVER

IN:07742-0010100 EX: 07742-0010

(2) VALVE GUIDE DRIVER ATTACHMENT

IN: 07943-MF50100 EX: 07943-MF50200

(1) VALVE GUIDE REAMER

IN: 07984-2000000

EX: 07984-6570100

CYLINDER HEADNALVE

H O NDA

VTSO OC

V ALVE SEAT INSPECTION / REFACING

Clean all intake and exh aust valves thoroughly to remove carbon deposits.

Apply a ligh t coating of Prussian Blue to each valve seat. Lap each valve and seat using a rubber hose or other hand-lapping tool.

Remove and inspect each valve.

CAUTION

Inspect the width of each valve seat.

STANDARD: 0.9-1.1 mm (0.0354-0.0433 in) SER VICE LIMIT: 1.50 mm 10.0591 in)

If the seat is too wide, too narrow or has low spots, the seat must be ground.

VALVE SEAT CUTTERS

Honda Valve Seat Cutters, grinder or equivalent valve seat refacing equipmen t are recommended to correct a worn va l ve seat .

NOTE

Follow the refacer manufactu rer's opera ting instruct ions.

CYLINDER HEAD/VALVE

VALVE SEAT R E FACING

Use a 45 degree cutter to remove any roughness or irregula ri ties from the seat.

NOTE

R eface the seat with a 45 degree cutter when a valve guide is replaced.

Use a 32 degree cutter to remove the top 1/4 of the existing valve seat material.

Use a 60 degree cutter to remove the bottom 1/4 of the old seat. Remove the cutter and inspect the area you have refaced.

Use a 45 degree f inish cutter and cut the seat to the proper width. Make sure that all pitting and irregu· larities are removed . R efinish if necessary.

c:iiJ\ H O NDA

VTSOOC

CYLINDER H E AD N ALV E

H O NDA

VTSO OC

Apply a thin coating of Prussian Blue to the valve seat. Press the valve th rough the valve guide and onto the seat to make a clear pattern.

NOTE

The location of the valve seat in relation to the valve face is very important for good seal i ng.

If the contact area is too h igh on the valve, the seat must be lowered usi ng a 32 degree flat cutter.

If the con tact area is too low on the valve, the seat must be raised usi ng a 60 degree inner cutter.

Refinish the seat to specifications, using a 45 degree f inish cutter.

After cutting the seat. apply lapping compou nd to the valve face, and lap th e valve using l igh t pressu re. After lapping, wash all residual compound of f the cylinder head and valve.

NOTE

CYLINDE R H EADNALV E

CYLINDER HEAD ASSEMBLY

I nstall the valve spring seal and a new stem seal . Lubricate each valve stem with molybdenum disul· fide grease and insert the valve into the valve guide. To avoid dama!ll! to the stem seal, tu rn the valve slowly when inserting.

I nstall the valve springs andl retai ners. The springs tigh tly wound coils should face in toward the com bustion chamber.

(1) VALVE SPR INGS

,,,,,...

(3) COTTERS (41 RETAINER

Q\ H O NDA.

VT500 C

(2) IN. V ALVE SPRINGS

NOTE

Springs wi th green pa in t are exhaust val ve

springs.

I nstall the valve cotters.

CAUTION

I 1 · I

THIS END TOWARDS \ COMBUSTION CHAMBER

(3) EX. VALVE SPRING

(1) VALVE SPRING COMPRESSOR

07757-0010000

Tap the valve stems gently with a sof t hammer to firm ly seat the cotters.

NOTE

Support the cyl inder head above the work bench surface to prevent possible valve da mage.

CYLI NDER HEAD INSTALLATIO N

Make sure that the cam chain guide bosses are in the grooves of the cylinder.

Clean the cylinder head surface of any gasket ma terial.

(2) GROOVES

I nstall the dowel pins and a new h ead gasket.

(1) HEAD GASKET

•

Install the cylinder head.

Install and tighten the 10 and 8 mm flange nuts and cylinder bolt to the specified torQue.

TORQUE:

10 mm nut: 35-45 N·m

(3.5-4.5 kg.m, 25-33 ft-lb)

8 mm nut: 20-25 N·m

(2.0-2.5 kg.m, 14-18 ft lb)

8 mm bolt: 20-25 N·m

(2.0-2.5 kg·m, 14-18 ft-lb)

6 mm bolt: 8-12 N·m

(0.8-1.2 kg-m,6-9 ft-lb)

Install the oil pipe and tighten the bolts.

TORQUE:

7 mm bolt: 8-12 N·m

(0.8-1.2 kg·m, 6-9 ft-lb)

10 mm bolt: 20-25 N·m

(2.0-2.5 kg-m, 4-18 ft-lb)

Tigh:en the cam chain tensioner bolts. Install the carburetor intake pipes.

CAMSHAFT INSTALLATION

Lubricate the camshaft journal surface of the cv·

linder head with molybdenum disulf ide grease.

Run the camshaft through the cam chain and install the cam sprocket on the shaft f lange.

(1) 10 mm NUT (2) 8 mm NUT

(3) 6 mm CYLINDER BOLT (4) 8 mm BOLT

(2) WASHERS (3) 10 mm BOLT

Place the camshaft into its correct positions.

Camshaft with tachometer gea r-F.cyl inder Camshaft whhou t tachometer gear -R .cylinder

Put each camshaft on the cylinder head with its lobe facing down.

Install the front cylinder camshaft f irst as shown

below.

While li fting the cam chain. rotate the crankshaf t clockwise and align the timing mark on the rotor with the index mark on the right crankcase.

Front cylinder ..• ....·"F.T"

Rear cylinder .....•.- - "R.T''

Al ign the ti ming marks oo the cam sprocket with the top of the cylinder head and place the cam chain on the sprocket.

Position the cam sprocket on the camshaft f lange.

NOTE

CAUTION

Apply a locking agent to the th reads and underside of the head of the cam sProcket bol t. I nstall the bolt, but do not tighten at this time.

Turn the crankshaft clockwise one tu m (360°). Apply a locking agent to the other cam sprocket bolt and install i t. Tighten the bolt to the specified torque.

TORQUE : 20-25 N·m

(2.0-2.5 kg-m. 14-18 ft·lb)

Tu rn the crankshaft clockwise one more tu rn and torque the remaining bolt to the same value.

Remove the 2 mm pin holding camshaft tensioner wedge A.

(1) TIMING MARK