Husqvarna 455 Rancher - Manual (Page 15)

English – 15
GENERAL SAFETY PRECAUTIONS
Checking chain lubrication
• Check the chain lubrication each time you refuel. See
instructions under the heading Lubricating the bar tip
sprocket.
Aim the tip of the bar at a light coloured surface about 20
cm (8 inches) away. After 1 minute running at 3/4 throttle
you should see a distinct line of oil on the light surface.
If the chain lubrication is not working:
• Check that the oil channel in the bar is not obstructed.
Clean if necessary.
• Check that the groove in the edge of the bar is clean.
Clean if necessary.
• Check that the bar tip sprocket turns freely and that the
lubricating hole in the tip sprocket is not blocked. Clean
and lubricate if necessary.
If the chain lubrication system is still not working after carrying
out the above checks and associated measures you should
contact your service agent.
Chain drive sprocket
The clutch drum is fitted with one of the following drive
sprockets:
A Spur sprocket (the chain sprocket is welded on the drum)
B Rim sprocket (replaceable)
Regularly check the degree of wear on the drive sprocket.
Replace if wear is excessive. Replace the drive sprocket
whenever you replace the chain.
Needle bearing lubrication
Both versions of sprockets have a needle bearing on the drive
shaft, which has to be greased regularly (once a week).
CAUTION! Use a high-quality bearing grease or engine oil.
See instructions under the heading Maintenance, Needle
bearing lubrication.
Checking wear on cutting equipment
Check the chain daily for:
• Visible cracks in rivets and links.
• Whether the chain is stiff.
• Whether rivets and links are badly worn.
Replace the saw chain if it exhibits any of the points above.
We recommend you compare the existing chain with a new
chain to decide how badly the existing chain is worn.
When the length of the cutting teeth has worn down to only 4
mm the chain must be replaced.