Great Plains NTA3007HD Operator Manual - Manual (Page 111)

Maintenance and Lubrication 107
04/04/2011 166-207M
Chain Maintenance
Initially check the drive chains after the first 10 hours of
drill use. The slack of new chains tends to increase dur-
ing the first few hours of operation due to seating. There-
after, check the chains every 100 hours.
Lubricate chains any time there is a chance of moisture,
and when being stored at the end of the planting season.
Chain Slack
Refer to Figure 111, which, for clarity, greatly exaggerates
slack, and omits the idlers.
1.
Measure the span for allowable slack:
Locate the longest span of each chain (usually the
span which does not run through the idlers).
2. Determine the ideal slack:
Long chains (over 91cm/36in): 2.1cm/m (
1 ⁄
4
in per ft)
Vertical short chains: 2.1cm/m ( 1 ⁄
4
in per foot)
Horizontal short chains: 4.2cm/m ( 1 ⁄
2
in per foot).
3. Measure the current slack :
Acting at a right angle to the chain span at the center
of the span, deflect the chain in both directions. The
slack is the distance of the movement.
4. Adjust the idlers for ideal slack.
Whenever mounting a chain, make sure the clip at the
removable link is oriented to minimize snags.
Refer to Figure 112 (arrow shows chain direction)
Install clip with open end facing away from direction of
chain travel (shown by gray or striped arrows in chain
routing diagrams).
Null4:
Maintenance
.eps
50%
Figure 111
Measuring Chain Slack
27264
2
1
1
Null4:
.eps
60%
Figure 112
Chain Clip Orientation
26482
2