Great Plains YP1220 Operator Manual - Manual (Page 64)

60 YP1220 Great Plains Manufacturing, Inc.
401-506M 03/14/2012
Chain Maintenance
Inspect and lubricate chains regularly. The slack of new
chains tends to increase during the first few hours of
operation due to seating.
Chain Slack
Check slack within the first 8 hours of operation and
tighten idlers as necessary.
Refer to Figure 67, 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 36in/91cm):
1 ⁄
4
in per foot
Vertical short chains: 1 ⁄
4
in per foot (2.1cm/m)
Horizontal short chains: 1 ⁄
2
in per foot (4.2cm/m).
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 68 (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)
Row Unit Chain Tension
The seed meter drive has a spring-loaded idler which
requires no adjusting. However, chain stretch may make
it necessary to shorten the chain.
Refer to Figure 69
For best chain tension the recommended vertical dis-
tance
between chain idlers is:
minimum: 1 ⁄
4
in (6.4mm)
maximum: 1 ⁄
2
in (12.7mm)
This measurement should be taken with opener parallel
arms
. horizontal. The front idler should be below
the rear idler .
FigureSpacer:
Figure 67
Measuring Chain Slack
27264
2
1
1
FigureSpacer
Figure 68
Chain Clip Orientation
26482
2
Figure 69
20 Series Meter Chain
28024
1
3
2
4
1
4 2
3