Husqvarna 340 EPA II Manuel D'utilisation page 18

Fit the bar over the bar bolts. Place the bar in its rearmost
position. Place the chain over the drive sprocket locate it in
the groove on the bar. Begin on the top edge of the bar.
Make sure that the edges of the cutting links are facing
forward on the top edge of the bar.
Install the clutch cover and locate the chain tensioner pin in
the clutch cover. Check that the chain's drive links fit correctly
over the drive sprocket and that the chain is correctly located
in the groove in the bar. Install the chain tensioning pulley but
do not tighten.
Tension the chain by turning the wheel down (+). The chain
should be tensioned until it does not sag from the underside
of the bar. See instructions under the heading Tensioning the
chain.
The chain is correctly tensioned when it does not sag from the
underside of the bar, but can still be turned easily by hand.
Hold up the bar tip and tighten the bar clutch by turning the
knob clockwise.
18 –
Canadian
ASSEMBLY
When fitting a new chain, the chain tension has to be checked
frequently until the chain is run-in. Check the chain tension
regularly. A correctly tensioned chain ensures good cutting
performance and long life.