Sullair 20/12 500 CFM, Operator'S Manual And Parts List

Page: 33 / 66

Section 6
MAINTENANCE
29
the components of the compressor are cool to the
touch.
1. Unscrew the minimum pressure/check valve (P/N
018498A) from the receiver cover.
2. Remove the hexagonal retaining cover from the
main body.
3. Remove the flat washer and heavy spring from the
main body.
4. Tap the piston assembly (with a screwdriver) from
the bottom of the main body and remove. The
seal ring will now be seen easily.
5. Remove the seal ring and discard.
6. Clean piston assembly and valve thoroughly.
7. Replace seal ring and coat the piston and seal
with Parker Super “O” Ring Seal or an equivalent
quality grease.
WARNING
!
Extreme caution should be used when removing
the cap from the body because there is spring ten-
sion on the cap.
(P/N 018498A)
* Repair Kit P/N 018514A
Figure 6-12 Minimum Pressure/ Check Valve
8. Reset piston assembly into the main body and re-
position spring and flat washer.
9. Replace retaining cap.
10. Reattach valve to receiver cover and reconnect all
piping.
PILOT VALVE MAINTENANCE
Ref er t o F igur e 6 -- 13 . P ilot v alv e ( P / N 407390) m ain-
tenance is quite minimal but a periodic cleaning is de-
sirable. The time between cleanings will vary de-
pending on operating conditions. In general, if the
voltage to the coils is correct, sluggish valve operat-
ing or excessive leakage will indicate that cleaning is
required. If so, order repair kit no. 042246 and follow
the procedure explained below.
WARNING
!
Turn off all power, relieve the pressure and discon-
nect coil lead wire to the valve before making re-
pairs.
It is necessary to remove the valve from the pipe line
for repairs.
PILOT VALVE DISASSEMBLY FOR GENERAL
CLEANING AND INSPECTION
Ref er t o F igur e 6 -- 13 . Depr es s ur iz e v alv e and t ur n off
electrical power supply. It is strongly recommended
that the valve be removed from the pipe line for ease
of maintenance. It it is not practical to remove the
valve from the pipe line, and resetting of strokes is re-
quired if a new Spare Parts kit is to be installed; con-
sult factory for special bonnet tools which are avail-
able. When consulting the factory, be sure to include
the valve catalog number and serial number from the
nameplate on the valve.
1. Disassemble valve in an orderly fashion paying
careful attention to the exploded view provided for
identification of parts.
2. Remove retaining cap or clip and slip the entire so-
lenoid enclosure off the solenoid base sub--as-
sembly.
CAUTION
!
When metal retaining clip disengages, it will spring
upward.
For explosion--proof/watertight enclosure, refer to
Installation and Maintenance Instructions Sheet,
Form No. V--5381.
3. Unscrew solenoid base sub--assembly and re-
move bonnet gasket. For explosion--proof/water-
tight enclosure, a special bonnet adapter wrench
is available. Order No. 102--649--1.
4. Unscrew disc guide caps (both ends) and remove
disc guide cap gaskets, upper and lower springs,
and discs.
CAUTION
!
Tag springs and discs as they are not interchange-
able and must be returned to the original location.
Tag upper and lower for ease of identification.