Haskel AG Serie Instructions De Fonctionnement Et D'entretien page 6

NOTE: Unless excessive leakage occurs, it is not advisable to replace the o-ring seal for the shank of the
stem. This requires disassembly of the air section. If replacement is required, care must be taken in
installing the Tru-Arc retainer concentrically as shown in figure 5. Use the 27375 pilot stem valve as
seating tool. Place the rubber valve face against the retainer and tap the top of the valve lightly with a
light hammer to evenly bend the legs of the retainer.
Test Procedure for Pilot Control Valves - 27375:
After relube of the spool and reassembly, if the drive cycles erratically, the following test procedure will
determine which of the pilot valves is faulty.
1. Remove the 17658-2 1/8" pipe plug in the upper end cap.
2. Install 0-160 psi pressure gauge.
3. Apply air pressure to the air drive inlet. Gauge will read zero pressure if lower pilot valve has not
been actuated. Gauge will read full pilot air pressure if upper pilot valve has not been actuated.
Correct pilot valve action will cause gauge to immediately rise or fall from zero to pilot air pressure. A
slow increase in gauge reading indicates leakage past the seat of the pilot valve in the valve end
cap. A slow decrease in pressure indicates leakage past the seat of the opposite pilot valve. Examine
and replace as required. Check also for external air leaks at plugs.
4. If drive takes 1 stroke and stops, this is probably due to either pilot valve stem being too short. See
the assembly drawing for description of procedure to determine proper stem length.
For Disassembly and Repair of Air Drive Section and Air Piston:
1. Remove (4) tie bolts.
2. Remove air barrel and static seal o-rings.
3. Remove seal on air piston.
4. Remove air piston and rod assembly in air drive section.
5. See applicable assembly drawing. Note that the air drive seals and bearings for the rods are part of
the gas section seal kit.
6. Inspect, replace and install all internal parts in air drive section per assembly drawing.
7. Relubricate air barrel with 50866 Haskel lubricant. Re-assemble drive in reverse order of disassembly
instructions. Care must be taken in disassembly and assembly that the flow and pilot tube o-rings be
on the flow and pilot tubes prior to assembly. Alternately (crosswise) torque tie rods to a maximum
torque of 16-18 ft-lbs.
Air Driven Gas Booster Compressor, 5-3/4" Drive AG Series • OM-3F
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