Great Plains NP4000B Operator Manual - Manual (Page 142)

138 2013+ NP4000/A/B Table of Contents Index Great Plains Manufacturing, Inc.
417-199M Table of Contents Index 2014-05-14
Chain Maintenance (Option)
Initially check the ground drive pump chains after the first
10 hours of applicator use. The slack of new chains
tends to increase during the first few hours of operation
due to seating. Thereafter, 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 93, 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 36 in. / 91 cm):
1 ⁄
4
in. per ft. (21 mm/m)
Vertical short chains:
1 ⁄
4
in. per ft. (21 mm/m)
Horizontal short chains:
1 ⁄
2
in. per ft. (42 mm/m)
3. Measure the current slack :
Acting at a right angle to the chain span at the centre
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 94 (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).
Figure 93
Measuring Chain Slack
27264
2
1
1
Figure 94
Chain Clip Orientation
26482
2