EMAK 63.4 cm3 Instruction manual

WORKSHOP MANUAL
63,4 cm³ chainsaws

General failures’ analysis
63,4 cm³ chainsaws

General failures’ analysis
63,4 cm³ chainsaws
p/n 001000392A
p/n 3055125
I.
III.
II.
p/n 001000785
Suggested tools
I. Emak tool kit
II. Compression tester: to check thermal group
III. Electronic tachometer: for 2 and 4 stroke engines, measurement range from 100 to 30,000 RPM

General failures’ analysis
63,4 cm³ chainsaws
Index
1) Performance
a) Compression test
b) Cylinder and piston inspection
c) Decompressor inspection
d) Cooling system cleaning
e) Muffler inspection
2) Fuel system
a) Fuel and fuel filter inspection
b) Fuel system test
c) Tank breather inspection
d) Engine seal test
e) Manifold inspection
3) Ignition system
a) Starter housing inspection
b) Spark plug inspection
c) Spark test
d) Flywheel-coil air gap inspection
e) Flywheel key inspection
4) Oil pump, bar and shock absorber
a) Oil tank breather inspection
b) Oil filter inspection
c) Sprocket/power mate ring inspection
d) Oil pump inspection
e) Chain brake inspection
f) Lubrication and bar maintenance
g) Shock absorber replacement
5) Tuning
a) Air filter inspection
b) Needle valve inspection
c) Carburetor inspection
d) Suggested tools for carburetion setting
e) Carburetion tuning
6) Tightening torques
7) Trouble shooting
a) The engine does not start
b) Low performance
c) Additional problems

General failures’ analysis
63,4 cm³ chainsaws
I
p/n 001000392A
1) Performance
a) Compression test
b) Cylinder and piston inspection
c) Decompressor inspection
d) Cooling system cleaning
e) Muffler inspection
a) Compression test
• Apply the Emak compression
tester (I) on cylinder. Pull
energetically the rope 10
times
• Verify that the compression
value in not less than 8 bar –
130 psi
• If the value in higher than
8 bar – 130 psi, start
inspection c), if lower, carry
on with inspection b)

General failures’ analysis
63,4 cm³ chainsaws
Tightening torque cylinder-screws
1,2 Kgm (106,20 in lb) + Loctite 243
Warning: during assembly
make sure the circlip has
the feet pointing up
Warning:
The arrow on the top of the
cylinder points towards the
exhaust port.
b) Cylinder and piston inspection
• Verify the diamond scoring on piston and the nickel-lining on cylinder. Replace if necessary
• Verify the piston rings wear using feeler gauge (gap max 1,0 mm)

General failures’ analysis
63,4 cm³ chainsaws
c) Decompressor inspection
Verify that the decompressor and the decompression hole on the cylinder is not closed to carbon deposits.
Clean and/or replace if necessary.

General failures’ analysis
63,4 cm³ chainsaws
d) Cooling system cleaning
Blow, with compressed air, cylinder fins, starter
case and flywheel
Important:
•Cleanweekly the cooling system. For heavy
duty work, clean it every day
• Use Loctite 243 to tighten plastic component
Tightening torque
Cover
0,4 kgm (35,4 in lb)
+ Loctite 243
Tightening toque cover-basement
0,4 kgm (35,4 in lb) + Loctite 243

General failures’ analysis
63,4 cm³ chainsaws
Tightening torque cover muffler-basement
0,6 kgm (52,1 in lb) + Loctite 243
Tightening torque muffler-cylinder
1,0 kgm (88,5 in lb) + Loctite 243
Back to index
e) Muffler inspection
If the muffler is blocked or damaged, clean or
replace it

General failures’ analysis
63,4 cm³ chainsaws
a) Fuel and fuel filter inspection
• Verify fuel quality odor
• Dismount and check periodically the fuel filter
and the sintered internal filter. In case of dirt or
oxidation, replace it
2) Fuel system
b) Fuel system test
• Apply the pressure gauge at the fuel line. Check
any possible leakage at 0,5 bar
• If the pressure is not stable, it may indicate
worn fuel system or loose at the carburetor
parts
Sintered
internal
filter
a) Fuel and fuel filter inspection
b) Fuel system test
c) Tank breather inspection
d) Engine seal test
e) Manifold inspection
Carburetor inspection
Go to

General failures’ analysis
63,4 cm³ chainsaws
II
c) Tank breather inspection
• Dismount the breather and check the components
• Apply the pressure gauge (I), supplied with Emak tool kit, at the breather valve and verify the correct
working in both ways. To check the inlet direction use the adaptor (II), supplied with the pressure gauge’s
box, as shown on the photo. Replace or clean if necessary
I
p/n 1043900
Breather sealing test:
0,2 – 0,3 bar
Breathing system test:
0,00 bar

General failures’ analysis
63,4 cm³ chainsaws
I
p/n 001000368B
III
III
p/n 001000005A
IV
d) Engine seal test
• Remove air filter, cover, air filter support,
carburetor and muffler. Cover the intake side
with insulator and exhaust side using the
special flanges supplied with Emak tool kit (I
and II). Tap the impulse’s tube with a cap (III)
and replace the decompressor with a special
cap (IV)
• The pressure has to remain stable at 0,5 bar. If
the engine looses pressure, find the leakage and
fix it. Repeat seal test

General failures’ analysis
63,4 cm³ chainsaws
e) Manifold inspection
Check the manifold for wear. Verify that the manifold’s rubber is not deteriorated or hardened and check that
there are no cuts or holes. Replace if necessary
Back to index

General failures’ analysis
63,4 cm³ chainsaws
3) Ignition system
a) Check housing inspection
b) Spark plug inspection
c) Spark test
d) Flywheel-coil air gap inspection
e) Flywheel key way inspection Wind the spring 7 times
ø 4,0 x 1035 mm
a) Starter housing inspection
Remove housing. Inspect parts for wear. If
necessary clean or replace
Important: grease moving parts

General failures’ analysis
63,4 cm³ chainsaws
(0,5 mm) I
p/n 001000515R
b) Spark plug inspection
Remove the spark plug and check the gap
between the electrodes (0,5 mm)
c) Spark test
• Fit the tester (I) between spark plug and spark
plug cap. Pull the rope and verify the current
• Replace the spark plug if necessary
• Check the two wires, ignition coil and switch

General failures’ analysis
63,4 cm³ chainsaws
II
cod. 001000004 III
cod. 001000782
d) Flywheel-coil air gap inspection
• Check the air gap using the shim (II-0,3 mm)
• Adjust if not correct
Tightening torque coil-screws
0,35 kgm (30,98 in lb) + Loctite 243
e) Flywheel key way inspection
• Remove flywheel with corrector tool (III)
• Inspect key way’s condition and position. If
necessary, replace or adjust
Tightening torque flywheel-nut
2 kgm (177,0 in lb)
Back to index

General failures’ analysis
63,4 cm³ chainsaws
4) Oil pump, bar and shock absorber
a) Oil tank breather inspection
b) Oil filter inspection
c) Sprocket/power mate ring inspection
d) Oil pump inspection
e) Chain brake inspection
f) Lubrication and bar maintenance
g) Shock absorber replacement
Make sure that the
height of the oil tank
breather is 1 mm lower
than bar face
Tightening torque crankcase-screws
0,8 kgm (69,44 in lb)
+ Loctite 243
a) Oil tank breather inspection
• Clean with compressed air
• Verify the quality of the bar and chain oil
b) Oil filter inspection
Check the oil filter. If it is dirty, clean it

General failures’ analysis
63,4 cm³ chainsaws
OK REPLACE
Attention: always replace the snap ring after
removing.
Attention: When reassembling the clutch make
sure that the worm gear drive spring (I) lodges
into the clutch drum correctly (II)
I
II
c) Sprocket/power mate ring inspection
Check the sprocket/power mate ring wear
periodically. Replacement is suggested every
100 hrs or before

General failures’ analysis
63,4 cm³ chainsaws
I
p/n 001000684
c) Oil pump inspection
• Insert the piston stop (I) in the spark plug hole and remove the clutch
• Remove the oil pump, check the pump and worm gear
Important: If the gear inside the pump is hard to turn, disassemble all components and clean them using Emak
detergent
Tightening torque clutch
4,5 kgm (398,3 in lb)
+ Loctite 270

General failures’ analysis
63,4 cm³ chainsaws
e) Chain brake inspection
Check the brake band for wear. This must be changed if the wear limit is less than 0,6 mm