Cylinder; Leakage Test - Stihl 4180 Series Manual

7.10 Upper Half of Crankcase
with Cylinder
– Remove the valves, b 7.9
– Remove the cam gear, b 7.4
– Remove the muffler, b 7.5
– Remove the carburetor, b 6.2.2
1
: Take out the screws (1 and 2).
: Remove spacer flange (3) and
tensioner for throttle cable (4).
1
: Take screws (1 and 2) out of the
spacer flange.
Series 4180 Powerhead
: Remove the gasket (1) from the
cylinder head.
Reassemble in the reverse
sequence.
– Use a new gasket.
4
1
2
3
: Tighten down the screws (1 and
2) firmly. b 3.4
Screw heads (1 and 2) must be
completely recessed in the spacer
flange after installation.
2
7.11

Leakage Test

Damaged oil seals and gaskets or
cracks in castings cause leaks.
Such faults allow supplementary air
to enter the engine and upset the
1
fuel-air mixture.
This may prevent proper lubrication
or cause it to fail completely.
The engine can be checked for
leaks with the carburetor and
crankcase tester 1106 850 2905
and the vacuum pump
0000 850 3501.
Preparations
– Set the slide control to STOP.
– Remove the shroud, b 5.7
2
– Remove the filter cover and air
filter, b 6.1
– Remove the filter housing and
gasket, b 6.1
– Open the tank cap to release
pressure and then close it again.
– Disconnect the fuel hoses and
impulse hose from the
carburetor, b 6.2.2
– Disconnect the throttle cable,
b 6.2.2
– Pull off the carburetor, b 6.2.2
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