Suzuki: Engine K6A-YH6. Manual - part 10

5-4

TESTS AND ADJUSTMENTS

5

IMPORTANT

The check and adjustment must be performed when 
engine is cold.

Continue turning the crankshaft so that each 
different cam lobe will point away from the shim face 
successively. Measure each valve clearance at this 
position. (All the valve clearances can be measured 
during two complete turns of crankshaft.)

Valve clearance and adjustment may be done in pairs 
(Example: #1 Intake valves, then #2 Intake valves, 
and so on.)

The valve clearance measurement must be 
performed with the timing chain installed in place.

Figure 5-8

3.

When the cam lobe (2) to be checked points 180° 
away from the shim face, measure the clearance 
between the camshaft and shim using a feeler gauge 
(3).

4.

Check measurement against valve clearance 
specification.

5.

Perform adjustment procedure if valve clearance is 
out of specification.

Adjustment

Figure 5-9

1.

If the valve clearance is out of specification, adjust it 
by replacing the shim (1).

2.

Ensure that the valve is closed for the shim being 
adjusted and turn the tappet to bring its cutaway (2) 
inward.

3.

Turn the crankshaft to open the valve needing 
adjustment.

Figure 5-10

4.

Remove the camshaft housing cap screws (3).

NOTE

The special tool stamped with “IN” must be used for 
intake camshaft and tool with “EX” for exhaust camshaft.

Check that the special tool is not pushing on the shim.

5.

Attach the special tool (4) with the camshaft housing 
cap screws. Torque to specification.

Tightening Torque: 97 lb-in. (11 N•m)

Required Tools

Tappet Holder: Jacobsen PN 4139726

TN0360

180

°

2

3

TN0361

2

1

TN0362

3

4

TESTS AND ADJUSTMENTS

5-5

5

Figure 5-11

6.

Turn the camshaft clockwise until the cam lobe is 
180° away from the tappet and remove the shim (5) 
from the tappet by lifting at the cutaway.

Figure 5-12

7.

Measure the thickness of the removed shim, and 
determine the required thickness of the new shim 
using the following equation:

IMPORTANT

If the value “A” equals an odd number, use a shim   
0.01 smaller than “A” value.

Shim Selection Chart

TN0363

5

TN0364

A = B + (C – 0.20 mm)

Where

 A

: Required thickness of new shim (mm)

B

: Thickness of removed shim (mm)

C

: Valve clearance measured (mm)

Part Number

Stamped 

Number

Thickness 

(mm)

4148102

218

2.18

4148103

220

2.20

4148104

222

2.22

4148105

224

2.24

4148106

226

2.26

4148107

228

2.28

4148108

230

2.30

4148109

232

2.32

4148110

234

2.34

4148111

236

2.36

4148112

238

2.38

4148113

240

2.40

4148114

242

2.42

4148115

244

2.44

4148116

246

2.46

4148117

248

2.48

4148118

250

2.50

4148119

252

2.52

4148120

254

2.54

4148121

256

2.56

4148122

258

2.58

4148123

260

2.60

4148124

262

2.62

4148125

264

2.64

4148126

266

2.66

4148127

268

2.68

4148128

270

2.70

4148129

272

2.72

4148130

274

2.74

4148131

276

2.76

4148132

278

2.78

4148133

280

2.80

4148134

282

2.82

5-6

TESTS AND ADJUSTMENTS

5

NOTE

Install the shim with its size marking facing tappet.

8.

Install the selected shim with its stamped number 
facing tappet side.

Figure 5-13

IMPORTANT

If the crankshaft is turned in the normal direction 
(turning the cam lobe clockwise), the valve may 
possibly hit the piston head.

9.

Turn camshaft counterclockwise until cam lobe has 
fully opened the valve.

10. Remove special tappet tool and reinstall cam 

housing cap screws.

11. Tighten the camshaft housing cap screws to 

specification

Camshaft Housing Cap Screws Torque: 97 lb-in. 
(11 N•m)

NOTICE

Installation Note

For installation procedure, reverse the sequence of 
removal.

Cylinder Compression Test

See Figure 5-14.

1.

Warm up the engine.

2.

Stop the engine, remove all the spark plugs and 
disconnect the cam angle sensor coupler.

Figure 5-14

3.

Install the special tools (1, 2, and 3) to the spark plug 
hole being checked.

4.

With the throttle fully open, operate the starter motor 
and check the maximum reading on the compression 
gauge.

4148135

284

2.84

4148136

286

2.86

4148137

288

2.88

4148138

290

2.90

4148139

292

2.92

4148140

294

2.94

4148141

296

2.96

4148142

298

2.98

4148143

300

3.00

Part Number

Stamped 

Number

Thickness 

(mm)

TN0365

6

After completing the valve clearance adjustment, 
check the clearance again to make sure it is 
within the specification.

Required Tools

Compression Gauge Set: Suzuki PN 09916-67011 or 
Equivalent
Compression Gauge Hose: Suzuki PN 09915-64530 
or Equivalent
Compression Gauge Hose Attachment B: Suzuki PN 
09915-64550 or Equivalent

1

Compression 
Gauge Set

3

Compression Gauge Hose 
Attachment

2

Compression 
Gauge Hose

TN0537

3

1

2

TESTS AND ADJUSTMENTS

5-7

5

NOTICE

5.

Carry out steps 3 and 4 above on all the cylinders.

6.

If the compression pressure is lower than the limit, 
check that the special tool is properly installed. If the 
installed condition is correct, the possible cause may 
be compression leak from piston ring or valve.

7.

After completing the inspection, install the spark 
plugs and connect cam angle sensor.

5.4 Lubrication System

Oil Pressure Test

See Figures 5-15 through 5-17.

1.

Check that the following items are satisfactory.

•

Oil Level

Refill

•

Oil Contamination

Replace

•

Oil Leakage

Repair

Figure 5-15

2.

Remove the oil pressure sending unit from the 
cylinder block. (See “Oil Pressure Sending Unit” on 
page 7-32.)

3.

Install the special tools (1 and 2) into the oil pressure 
sending unit hole.

4.

Warm up the engine.

Figure 5-16

5.

Raise engine speed to 4000 rpm and measure the oil 
pressure on the gauge (3).

Oil Pressure—Minimum at 4,000 rpm: 40 psi 
(276 kPa)

6.

If the oil pressure measurement is out of 
specification, check the oil pump and oil filter.

Compression Pressure at 400 rpm

Standard:

psi
kPa 
(kgf/cm²)

178.4
1,230 
(12.5)

Service limit

psi
kPa 
(kgf/cm²)

134.9
930 
(9.5)

Difference 
Between 
Cylinders
Maximum

psi
kPa 
(kgf/cm²)

14.2
98 
(1.0)

If the specified speed (400 rpm) is not attainable 
due to lowered battery voltage, recharge the 
battery and carry out the inspection again.

Required Tools

Oil Pressure Gauge: Suzuki PN 09915-77311 or 
Equivalent

Oil Pressure Gauge Attachment: Suzuki PN 
09915-78211 or Equivalent

TN0536

1

2

TN0353

3