Husqvarna 2011 TE 630 Workshop Manual page 178

ENGINE REASSEMBLY
Install mesh filters (17) and their cover (18) and tighten the screws (19) with an
8 mm wrench (see Section "X" for tightening torque figures).
Insert bushing (20) with its O-ring (21); the O-ring groove must be facing into
the engine.
Cover the upper section of the engine with a cloth, a sponge or the like to prevent
screws or other parts from accidentally falling into the engine.
H.22 Part. N. 8000 H2051 (02-2010)