XVIII. Part Inspection of Pilot Valve
After the valve has been disassembled, all parts should be given a visual inspection. Some key areas to check with
the boundaries for reworking parts are listed blow.
A. 39PV07/37
1. Main Piston: Galling or excessive wear on the small
diameter end where it engages the spring seals or
on the spherical bearing surface. Any corrosion or
pitting that appears detrimental to the function of
the valve. The part can be polished as long as the
outside diameter of the stem remains at .243 ±
.001” (6.18 ± 0.03 mm). The stem itself must have a
T.I.R of .001” (0.03 mm) along its length. The upper
diameter where the Spring Seal (Main Piston) rides
must be 1.495 ± .001 (37.97 ± 0.03 mm) on 39PV07
model or .970 ± .001” (24.64 ± 0.03 mm) on 39PV37.
A surface finish of 8 RMS must be maintained for
proper sealing on these surfaces.
2. Insert Top: Galling or excessive wear on the
inside diameter that guides the Main Piston.
Check for any corrosion or pitting. Also, check
for galling of threads.
3. Insert Bottom: Galling or excessive wear on
the inside diameter that guides the Main Piston.
Check for any corrosion or pitting.
4. Adjuster Top: Galling or excessive wear on the
inside diameter that guides the Main Piston.
Check for any corrosion or pitting. Also, check
for galling of threads.
5. Adjuster Bottom: Galling or excessive wear on
the inside diameter that guides the Main Piston.
Check for any corrosion or pitting. Also, check for
galling of threads.
6
. Top Plate: Galling or excessive wear on the
inside diameter that guides the Main Piston.
Check for any corrosion or pitting. Also, check for
galling of threads.
7. Bonnet: Check for any corrosion or pitting. Also,
check for galling of threads for the compression
screw and where it attaches to the Pilot Base.
8. Compression Screw: Galling at the spherical
bearing surface or in the thread. Check for any
corrosion or pitting.
9. Spring Washer(s): Galling at the spherical bearing
surface. Check for any corrosion or pitting.
10. Pilot Base: Check for any corrosion or pitting.
Also, check for galling of threads.
11. Spring: Check for any corrosion or pitting.
B. 39MV07
1. Main Piston: Galling or excessive wear on the small
diameter end where it engages the spring seals or
on the spherical bearing surface. Any corrosion or
pitting that appears detrimental to the function of
the valve. The part can be polished as long as the
outside diameter of the stem remains at .243 ±
.001” (6.17 ± 0.03 mm). The stem itself must have a
T.I.R of .001” (0.03 mm) along its length. The upper
diameter where the Spring Seal (Main Piston) rides
must be 1.495 ± .001 (37.97 ± 0.03 mm) on 39PV07
model or .970 ± .001” (24.64 ± 0.03 mm) on 39PV37.
A surface finish of 8 RMS must be maintained for
proper sealing on these surfaces.
2. Insert Top: Galling or excessive wear on the
inside diameter that guides the Main Piston.
Check for any corrosion or pitting. Also, check
for galling of threads.
3. Insert Bottom: Galling or excessive wear on
the inside diameter that guides the Main Piston.
Check for any corrosion or pitting.
4. Adjuster Top: Galling or excessive wear on the
inside diameter that guides the Main Piston.
Check for any corrosion or pitting. Also, check
for galling of threads.
5. Adjuster Bottom: Galling or excessive wear on
the inside diameter that guides the Main Piston.
Check for any corrosion or pitting. Also, check for
galling of threads.
6. Top Plate: Galling or excessive wear on the
inside diameter that guides the Main Piston.
Check for any corrosion or pitting. Also, check for
galling of threads.
7. Bonnet: Check for any corrosion or pitting. Also,
check for galling of threads for the compression
screw and where it attaches to the Pilot Base.
8. Compression Screw: Galling at the spherical
bearing surface or in the thread. Check for any
corrosion or pitting.
9. Spring Washer(s): Galling at the spherical bearing
surface. Check for any corrosion or pitting.
10. Pilot Base: Check for any corrosion or pitting.
Also, check for galling of threads.
11. Spring: Check for any corrosion or pitting.
Consolidated 2900 Series POSRV Maintenance Manual
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