Vent Valve - Stihl 020 T Service Manual

9.2

Vent Valve

A valve is installed in the tank wall to
keep internal tank pressure equal to
atmospheric pressure.
Cleaning the valve
• Unscrew the oil tank filler cap.
• Drain the oil tank.
• Remove the chain sprocket –
see 3.3.
• Take out the screws (1).
• Remove the cover (2).
• Blow valve clear with
compressed air (from outside).
STIHL 020 T
• Flush out the oil tank.
• Refit the cover.
• Fit the chain sprocket - see 3.3.
• Fit the oil tank filler cap.
Replacing vent valve
• Unscrew the oil tank filler cap.
• Remove the chain sprocket –
see 3.3.
• Take out the screws.
• Remove the cover.
• Pull out the upper bumper strip.
• Use a 5 mm (0.2") drift to careful-
ly drive the vent valve out of the
crankcase from inside the tank.
• Place vent valve in position with
its smaller bore facing outwards.
• Use a 7 mm (0.3") drift to careful-
ly push home the valve until it is
recessed about 1 mm (0.04") be-
low the housing face.
• Fit the bumper strip.
• Fit the cover.
• Fit the chain sprocket - see 3.3.
• Fit the oil tank filler cap.
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