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Nelson Irrigation Corporation 848 Airport Rd. Walla Walla, WA 99362 USA Tel: 509.525.7660 Fax: 509.525.7907 E-mail: [email protected] Web site: www.nelsonirrigation.com
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SR/SRA150 MAINTENANCE
SEE SR/SRA150 PARTS LISTS FOR COMPLETE PARTS LIST AND DESCRIPTION
DISASSEMBLY
REASSEMBLY
STEP 4
Inspect seal spacer and counter-
weight spacer for wear. If spacers
show excessive wear, replace both
spacers and #6600 Seals. To
remove seals, drive thin-bladed
screwdriver under lip of seal and
pry seal out. To replace seals, use
block of wood over seal making
sure lip is to the outside, and secure
by lightly tapping on wooden block
until seal lip is flush with hub.
STEP 5
Remove #10070-001 Cap
Assem-bly. Using external retaining
ring pliers, remove #8323-017
Retaining Ring. Pull Shift lever from
mount. A gear puller will help in
removing the lever.
STEP 9
Snap in two #10067-001 Arm
Cap Assemblies. Install two
#6565 Retaining Rings. Arm
must have free movement at this
point. If arm feels sticky, assure
that lip seals at counterweight and
right arm hub are not rubbing on
each other.
STEP 10
Mount trip lever assembly along
with spring guide onto their
respective pins. Install #8323-04
Retaining Ring. Install #8263 Cap
using two #8311 Screws making
sure #8265 gasket is in place.
Install #8409 Washer and #7814
Cotter Pin onto spring guide.
STEP 3
Using a thin-bladed screwdriver,
push #8327-001 Spacer back
into arm hub. Holding onto
counterweight, remove arm and
weight. Be careful not to damage
seals.
STEP 8
Holding counterweight in place on
the left side of shift lever, roll drive arm
into position shown by pushing on the
left arm bearing. Work #8327-001
Spacer into seal on counterweight.
Be sure spacer is correctly positioned
in counterweight to prevent cutting
of the seal lip. Push shaft through
the bearings and spacers and
assemble #6603 Nut. Torque to 25
ft. lbs. using two 11/16” sockets.
STEP 2 (Drive Arm)
Using internal retaining ring pliers,
remove two #6565 Retaining
Rings from both arm hubs. Remove
two #10067-001 Arm Caps. Using
two 11/16” sockets, loosen and
remove one #6603 Nut from left
side of arm. Holding the opposite
#6603 Nut, pull shaft free from hub.
STEP 7 (Drive Arm)
Lubricate #6600 Seal lips with
#9673 Silicone Grease. Install
#8327-001 Spacer flush with
#6600 Seal in left arm hub. Insert
#6607-001 (coated spacer) in right
arm hub and #6607 (uncoated
spacer) in left counterweight seal
(or a second #6607-001 coated
spacer). Start #8297 Shaft into right
arm hub.
STEP 1 (Trip Lever)
Remove #6714 Cotter Pin from
#8197 Pin. Remove two #8311
Screws and #8263 Cap. Using
small retaining ring pliers, remove
#8323-004 Retaining Ring. Pull
entire trip lever assembly and
spring guide from gun. At this time
inspect wear on #8282 Follower.
Replace if worn.
STEP 6 (Shift Lever)
At the upper portion of the gun,
inspect the mount shaft for wear.
Press the #8589 Shift Lever
assembly onto the mount. With
external retaining ring pliers,
snap the #8323-017 Retaining
Ring on. Be sure #8272 Cap
Gasket is in place and in good
condition. Replace #10070-001
Cap Assembly
Spring
Guide
#8197
#8282
#8323-004
#6600
Counterweight
#8323-017
Mount Shaft
#10070-001
#8589
Left Hub
Right Hub
#8327-001
#8465
#10067-001