172-65169MA-08 (MC-COS Multi-control Valve) 28 May 2010
24
Disassembling the Pilot Section
The diaphragm is removed by utilizing the notch in the pilot body. Loosen and
remove the pilot valve seat with a box wrench. Pick up the pilot valve and the pilot
valve spring with a pair of tweezers. Loosen and remove the pilot screen holder to
remove the pilot screen.
Check for any fault on the seat of the pilot valve, flaws on the gaskets, and clogging
of the pilot screen. Check for deformation, corrosion or faults on the diaphragm. The
diaphragm should be convex (open downward), with the printed UP mark on the top.
15 – 50 mm (
1
/
2
– 2 in)
65 – 100 mm (2
1
/
2
– 4 in)
Diaphragm
Diaphragm
Pilot Valve Seat
(with gasket)
Pilot Valve Seat
(with gasket)
Pilot Valve Stem
Pilot Valve Stem
Pilot Valve
Pilot Valve
Pilot Spring
Pilot Spring
Bolt
Bolt
Notch
Notch
Pilot Body
Pilot Body
Pilot Screen
Pilot Screen
Pilot Screen
Holder (with
gasket)
Pilot Screen Holder
(with gasket)
Pilot Cover
Upper Pilot Body Gasket
Upper Pilot Body Gasket
Lower
Pilot
Body Gasket
Connector