Stihl 029, 039 - 10.2 Vent Valve; 10.3 Removing and Installing the Oil Pump

STIHL 029, 039 56
10.3 Removing and Installing
the Oil Pump
Top:
Oil filler cap
Bottom:
Pushing bead of suction
hose into position
Top:
Vent valve
Bottom:
Installed position of valve a =
approx. 1 mm (3/64")
Top:
Removing the worm
Bottom:
Removing suction hose from oil
pump nipple
10.2 Vent Valve
- Remove the clutch - see 3.2.
- Pull the worm and drive spring off
the crankshaft stub.
- Take the spring off the worm.
- Push the suction hose off the
nipple on the oil pump.
A valve is installed in the tank wall to
keep internal tank pressure equal to
atmospheric pressure.
- Drain the oil tank.
- Use a 7 mm (9/32") dia. drift to
carefully drive the vent valve into
the engine housing and then
remove it from the oil tank.
- Carefully press in the new valve
until it is about 1 mm (3/64") below
the face of the housing.
- Remove the oil filler cap and the
cap retainer. Flush out the oil tank.
Assembly is a reversal of the
disassembly sequence.
Note: Coat the bead of the suction
hose with oil to simplify fitting.