Iron Curtain Aeration Pump Repair Instructions - Hellenbrand Iron curtain system 2.0 Owner's Manual

Iron Curtain Aeration Pump Repair Instructions

Air pump must be removed from Aeration Tank and have
power supply disconnected before proceeding.
1. Remove four front cover screws and remove front
cover and cover gasket.
2. Remove four pump head screws and remove pump
head.
3. Remove valve plate assembly.
4. Remove felt air filter on side of pump with a flat screw
driver prying under the flat center retainer.
5. Remove piston sleeve from connecting rod as-
sembly.
6. Using an 1/8" allen wrench through the air intake hole
loosen eccentric/bearing and piston connecting rod
assembly set screw and remove eccentric/bearing
and connecting rod assembly.
7A. If eccentric & bearing assembly need replacing: Us-
ing a 1/8 allen wrench through air intake hole, loosen
eccentric & bearing assembly screw and remove ec-
centric & bearing assembly. Remove piston sleeve
from connecting rod assembly. Remove valve flapper
screw and valve flapper. Remove intake valve plate
screws and remove ramped valve plate and piston
cup. Install new piston cup on connecting rod. Place
a dab of silicone caulk in the center dimple on bottom
side of ramped valve plate and install ramped valve
plate and intake valve plate screws (12" lbs.) mak-
ing sure the intake hole is aligned in the connecting
rod, piston cup and ramped valve plate. Install new
valve flapper and valve screw (12" lbs.). Slide new
piston sleeve upwards over connecting rod assembly
starting from the bottom, forcing new piston cup to
curve upwards inside piston sleeve. Note: If piston
sleeve slides over the top of connecting rod assembly,
reinstall, starting from the bottom.
8. If installing new connecting rod assembly, slide new
piston sleeve upwards over connecting rod assembly
starting from the bottom, forcing new piston cup to
curve upwards inside piston sleeve. Note: If piston
sleeve slides over top of connecting rod assembly,
reinstall, starting from the bottom.
9. From the top of the pump insert connecting rod/ec-
centric bearing assembly with set screw facing air filter
holes. Install on motor shaft all the way and tighten
set screw (8 inch pounds) Note: Set screw should
tighten onto flat spot on motor shaft.
10. Remove exhaust valve flapper screw, valve keeper strip,
valve flapper, valve flapper o-ring and piston sleeve
o-ring from valve plate. Lubricate new o-rings with
silicone lubricant to hold o-rings in place and install
in valve plate. Install new valve flapper, valve keeper
strip and exhaust valve flapper screw (12" lbs.) in valve
plate.
11. Install valve plate on pump, aligning piston sleeve o-
ring with top of piston sleeve.
12. Remove o-ring from pump head. Place 3-4 small dabs
of silicone lubricant in pump head o-ring groove to hold
o-ring in place and install o-ring in pump head.
13. Install pump head on pump, aligning exhaust port
with front of pump. Install four pump head screws and
tighten (48" lbs.).
14. Remove any remaining gasket material from front
cover and pump front and make sure both surfaces
are clean.
15. Install new front cover gasket with burr side in. Install
front cover and four cover screws and tighten screws
(20" lbs.).
16. Air pumps manufactured after 11/94 use an air filter
with a hole in the center and a plastic press in retainer
to hold it in place. To replace air filter, order p/n 74-
641169 Air Filter and Retainer. Place air filter in place
5