Air Driven Air Amplifiers, AA-8, AA-15 & AA-30 • OM-15A
6
Test procedure for pilot control valve:
After reassembly, if the pump will not cycle or “short cycles”, the following test procedure will determine
which of the pilot valves is faulty.
1. Remove the 17658-2 1/8” pipe plug in 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 drive pressure if
upper
pilot valve has not been actuated. Correct
pilot valve action will cause gauge to immediately rise or fall from zero to drive pressure. A slow
increase in gauge reading indicates leakage in lower pilot valve or 568017 o-ring on inside end of
spool or 568020 o-ring on the inside end of the sleeve. A slow decrease in pressure indicates upper
valve or pilot tube end seals are faulty and repair is necessary. Check also for external air leaks at
plugs or worn 568015 o-ring inside exhaust fitting.
Disassembly and Repair of:
Air Drive Section and Air Piston
1. Remove (4) tie bolts. Then remove upper cap.
2. Remove air barrel and static seal o-rings.
3. Remove seal-on air piston.
Pump Section and Pump Piston
4. Remove high pressure end cap.
5. Remove, pin and nut on pump piston.
6. Refer to assembly drawing for further removal and reinstallation of piston parts. Do not use lubricants
of any type. These parts operate dry.
7. Inspect bore of high pressure barrel. Replace if worn or scratched.
8. Assemble all pump piston parts and tighten nut
while confined within barrel bore
.
Drive Reassembly
9. Inspect, replace and install all parts in air drive section per individual assembly drawing.
10. Relubricate air barrel with 50866 Haskel lubricant.
11. Alternately (cross-wise) torque air drive tie rods to a maximum torque of 16-18 ft-lbs.
Check Valves
Remove, clean, and inspect parts per individual assembly drawing. Replace any parts if damaged.
