172-65175MA-13 (COS Pressure Reducing Valve) 16 Feb 2022
18
Disassembling the Pilot Section
The diaphragm is removed by utilizing the notch in the pilot body. Loosen the pilot
valve seat with a box wrench and remove it. Lift the pilot valve spring up and out with
a pair of tweezers. Then loosen and remove the screen holder to remove the screen.
Check for any fault on the seat of the pilot valve, flaws on the gaskets, and
clogging of the 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 to 50 mm (
1
/
2
to 2 in)
65 to 100 mm (2
1
/
2
to 4 in)
Diaphragm
Pilot Valve Seat
& Gasket
Pilot Valve
Pilot Valve Spring
Plug
Pilot Body
Gasket
Notch
Hex Bolt
Pilot Screen
Pilot Screen Holder
& Gasket
Diaphragm
Pilot Valve Seat
& Gasket
Pilot Valve
Pilot Valve Spring
Plug
Hex Bolt
Pilot Body
Gasket
Notch
Connecting
Tubes
Hex Bolt
Pilot Cover
Pilot Screen
Pilot Screen Holder
& Gasket