8
Repairs (cont.)
If after inspection of the rear tuning spring stack,
the front stack is suspected, use the ARMATURE
REPLACEMENT procedure as a guide for
re-assembly with special attention to the washer
shaped spacers between the spring bar and armature.
Carefully examine each tuning spring for signs of
delamination or breakage, especially in the area next
to the spring shims. A failed spring can be recognized
by the appearance of the spring surface. If this surface
is discolored or has a patchy whitish appearance,
perhaps accompanied by surface burying or other
irregularity, the spring is defective and should be
replaced with a new spring ordered from the parts list.
If the feeder still exhibits signs of spring malfunction
after the tuning spring has been checked and replaced,
check the two cylindrical elastomer springs after first
inserting the two gap spacers, then removing the
spring lever arms, and finally removing the elastomer
springs in the following manner:
1. Lay the unit on its side, making sure that the gap
spacers stay in place, and use a small hammer
and flattened round bar or dowel to tap the
elastomer spring out of the body housing. Next,
support the tiebar with a small block between the
tiebar and work surface, and tap the elastomer
spring out of the tiebar.
2. Carefully examine both springs for signs of failure
and replace if such signs are found. A failed
spring will exhibit one or more of the
following characteristics:
A. Looseness of the spring combined with signs
of rubbing or abrasion at the outer surface of
the cylinder. Looseness of the metal sleeve.
B. Small crack in the elastomer around the end
of the metal sleeve, possibly with small
abraded particles of the elastomer present.
C. Tackiness of the elastomer around the metal
sleeve and at the outer surface of the cylinder,
possibly with some outward bulging of
the elastomer.
3. In replacing the elastomer springs, lay the unit
on its side so that the chamfered ends of the
spring holes are up. After making sure that the
holes and their chamfered ends are clean and
free from obstructions, lubricate the elastomer
spring with a solution of water and 10% of liquid
dishwasher soap (NEVER use a petroleum or
silicone product) and press them partly into place
with the thumbs. Then tap the springs back into
place, again using the small supporting block
between tiebar and work surface. Make sure that
the springs go in straight and protrude equally at
both ends of both spring holes.
4. Replace the lever arms, tightening the two
fastening bolts securely, and remove the two
gap spacers. If a new elastomer spring has
been installed, it may be necessary to retune the
feeder. See Tuning Guide.
ARMATURE REPLACEMENT
Refer to the Parts List Drawing and Figs. 4, 5, 6 & 7.
Prolonged striking may damage the armature to an
extent that it will have to be replaced. If this should
become necessary, order a new armature from the
parts list and begin by following the same instructions
as for coil replacement.
1. Continue by removing, in order, the bolts securing
(A) the upper end of the front tuning spring
stacks to the spring bar and (B) the spring bar to
the armature. Retain the washer shaped spacers
located between the spring bar and armature.
2. Remove the bolts securing the elastomer
diaphragm to the body housing and lift the
armature out of the body cavity.
CAUTION
Make sure that all of the fasteners in the assembly
are tight or torqued to spec at all times. Periodic
checks for tightness should be made to insure
against possible malfunction or damage due to
loose parts.
Part Bolt Size Torque
m-kgs ft-lbs
Rear Spring Bolts M8-1.25 2.8 20.2
Front Tie Bar Bolts M8-1.25 2.8 20.2
Elastomer Nut M12-1.75 7.4 53.5
Front Spring Bolts M8-1.25 2.8 20.2
Electrical Assembly Bolts M8-1.25 2.8 20.2
Diaphragm Bolts M8-1.25 2.8 20.2
Tray Bolt M8-1.25 3.0 22
Table 1
Torque Chart HS36
