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(88). If it is worn badly, cracked, or broken, replace the
(3)  Remove valve spool (84) with extreme
entire valve assembly.
care. To remove valve spool (84), hold valve assembly
in both hands with stub shaft pointing downward. Push
(5)  Examine the spool (84) surface for nicks
lightly on valve spool with a small rod by inserting rod
and burrs. If any are found, they may be removed with
through openings in valve cap (91) until spool Is far
a very fine hone. A slight polishing is normal on the
enough out of valve that it may be grasped by the hand.
valving surfaces.
Withdraw spool with a steady oscillating pull to prevent
jamming.  If slight sticking occurs, make a gentle
(6)  Examine the valve body bore for nicks or
attempt to reverse withdrawal procedure. If this does
burrs. If any are found, they can be removed with light
not free the spool, it has become cocked in the valve
crocus cloth until the spool turns freely in the body. Be
body bore. Do not attempt to force the spool in or out if
careful not to remove any stock from the surface of the
it becomes cocked.
In this case, continue to
body. As on the spool, a slight polishing is normal on
disassemble the valve assembly as follows and return to
the valving surfaces.
the spool as described below.
CAUTION
6-152.
VALVE ASSEMBLY. Proceed as follows:
(1)  Lubricate  three  valve  ring  back-up
The diametrical clearance between the valve
packings (86) in SAE 10 engine oil. Assemble in three
body and the spool may be as low as 0.004
ring grooves on the valve body (87).  Assemble the
Inch.  The slightest cocking of the spool may
valve rings (85) in the ring grooves over the back-up
jam it in the valve body.
packings by carefully slipping the rings over the valve
body.  The rings may appear loose or twisted in the
(4)  Remove the stub shaft (88), torsion bar
grooves, but the heat of the oil after assembly will cause
and valve cap assembly (91) by holding the valve
them to tighten.
assembly in both hands as before, only with thumbs on
valve body.  Rap torsion bar lightly against the work
(2)  Install new valve spool dampener packing
bench. This will dislodge the cap from the valve body.
(83) in valve spool (84) groove.
If the valve spool has become cocked as described
above, it can now be freed. By visual inspection on a
(3)  Assemble the stub shaft in the valve
flat surface it can be determined in which direction the
body. Align groove in valve cap (91) with pin in valve
spool is cocked. A few very light taps with a Iight soft
body. Tap lightly on cap with plastic or rawhide mallet
plastic or rawhide mallet should align the spool in tile
until cap is against shoulder in valve body with valve
bore and free it.
body pin in cap groove.
CAUTION
CAUTION
Make sure groove and pin are in line before
Do not tap with anything metallic. If spool can
tapping on cap.  Hold these parts together
be rotated, it can be removed.
during the rest of the assembly.
(5)  Remove dampener seal packing (83) from
(4)  Lubricate valve spool with SAE 10 engine
spool and discard.
oil. Slide spool over stub shaft with notch toward valve
body. Align notch with spool drive pin in stub shaft and
(6)  Where the valve rings (85) show evidence
carefully engage spool in valve body bore. Push the
of excessive wear, carefully cut rings and ring back-up
spool evenly and slowly with a slight oscillating motion
packing (86), remove and discard. The valve rings are
until spool reaches drive pin. Rotate the spool slowly
made of filled teflon and it is very unusual that
with pressure until the notch engages the pin. Before
replacement is required.
pushing the spool completely in, make sure the
dampener packing is evenly distributed in the spool
6-151.
VALVE INSPECTION. Proceed as follows:
groove.  Slowly push the spool completely In.  Take
(1)  If the valve assembly leaks externally
extreme care not to cut or pinch the packing.
around the torsion bar (91) replace the entire assembly.
CAUTION
Because the clearance between the spool and
(2)  Check the pin in the valve body (87)
the valve body is very small, extreme care must
which engages the cap. If It is badly damaged, replace
be taken when assembling these parts.
the entire valve assembly.
(5)  Place seal protecting tool over stub shaft.
(3)  Check the worm pin groove (the smaller
Slide spool spring over seal protector and work spool
of the two) in the valve body). If It is damaged, replace
spring (82) down until it is seated in stub shaft groove.
the entire valve assembly.
Take care not to mar sealing surface of stub shaft.
(4)
Check the spool drive pin in the stub shaft
6-38

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