VALVE INSPECTION

(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

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