To Do A Check Of The Spur Sprocket; To Lubricate The Needle Bearing; To Do A Check Of The Guide Bar; To Examine The Cutting Equipment - Husqvarna 439 Manual Del Usuario

To do a check of the spur sprocket

The clutch drum has a spur sprocket that is welded on
the clutch drum.
• Regularly do a visual check of the degree of wear on
the spur sprocket. Replace the clutch drum with the
spur sprocket if there is too much wear.

To lubricate the needle bearing

1. Pull the front hand guard rearward to disengage the
chain brake.
2. Loosen the bar nuts and remove the clutch cover.
Note: Some models have only one bar nut.
3. Put the product on a stable surface with the clutch
drum up.
4. Remove the clutch drum and lubricate the needle
bearing with a grease gun. Use engine oil or a
bearing grease of high quality.

To examine the cutting equipment

1. Make sure that there are no cracks in rivets and links
and that no rivets are loose. Replace if it is
necessary.
2. Make sure that the saw chain is easy to bend.
Replace the saw chain if it is rigid.
823 - 005 -
3. Compare the saw chain with a new saw chain to
examine if the rivets and links are worn.
4. Replace the saw chain when the longest part of the
cutting tooth is less than 4 mm/0.16 in. Also replace
the saw chain if there are cracks on the cutters.

To do a check of the guide bar

1. Make sure that the oil channel is not blocked. Clean
if it is necessary.
2. Examine if there are burrs on the edges of the guide
bar. Remove the burrs using a file.
3. Clean the groove in the guide bar.
4. Examine the groove in the guide bar for wear.
Replace the guide bar if it is necessary.
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