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Nelson Irrigation Corporation 848 Airport Rd. Walla Walla, WA 99362-2271 USA Tel: 509.525.7660 Fax: 509.525.7907 [email protected] Web site: www.nelsonirrigation.com
10/13
SR75 BIG GUN MAINTENANCE
SEE FRONT FOR DRIVE ARM ASSEMBLY COMPONENTS / SEE SR75 PARTS LIST FOR COMPLETE PARTS LIST AND DESCRIPTIONS
DISASSEMBLY
STEP 1 (Trip Lever)
Remove two #8311 screws and
#10185 cap.
STEP 2
Using small retaining ring pliers,
remove #8323-201 ring.
STEP 3
Remove one #8311 screw from the
shift stop bracket. Rotate the trip
lever to pull follower from spring
guide. Pull entire trip lever assembly
from gun. Inspect wear on the
#8282 follower and #8193 pin.
STEP 4 (Drive Arm)
Remove four #8311 screws.
Remove #10231 cap.
STEP 5
Using an 11/16” socket, remove the
#6603 nut from left side of arm.
#8193 Pin
#8282
Follower
Spring Guide
#8323-201
#8282
STEP 6
Holding the range tube, pull drive
arm from the right side until it is
free from hub.
STEP 7
Inspect both left and right #6598
ball bearings. Replace if worn or
corroded. Inspect #6600 seals
as well. Lubricate seal with silicon
grease prior to reassembly.
STEP 8 (Shift Lever)
Remove two #8311 screws and
the #10364 cap. Using retaining
ring pliers, remove #8323-212
ring.
STEP 9
Pull #10226-004 shift lever from
mount. Inspect the mount shaft
and shift lever bushing for wear.
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