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13.0 TECHNICAL ISSUES.
13.1 BELT TENSION ADJUSTMENT.
The main rotor is driven directly from the gearbox via 2 V-belts at the right side of the head.
At the left side, the V belt drive for the second rotor is taken from the main rotor.
Both belts are tensioned via an identical idler.
Tensioning the belts goes as follows, see Fig 7:
1.
Switch off engine and lower the head on the ground.
2.
Remove the protection cover 7. NOTE. The cover at the left side ( second rotor) can
only be removed when the head is fully down or better the main frame is fully up.
Disassemble the cable 18 and spring 16 (fig 5), and move the main frame up via the
support jack. Next the cover can be removed.
3.
Check the tension. When a force of 150 N (33 lbs) is applied per belt, A should be 5-
10 mm ( ¼”- ½”).
4.
If the tension isn’t correct, slacken nut 4 and push the idler 5 down by hand. The
idler will slide into its support plate 6. Tighten nut 4 and check the tension as
mentioned under 3).
