Jordan Valve Mark 508 Series – Tank Blanketing Valve - Manual (Page 2)

Maintenance
Refer to the drawings for the proper orientation of the parts
and for proper nomenclature.
A. DIAPHRAGM OR GASKET REPLACEMENT
1. Remove all pressure from the line as outlined under WARNING.
2. Remove the compression of the adjusting spring (22) by ro-
tating the adjusting screw (19) counterclockwise.
3. Loosen the spring housing bolts (16) and remove spring
housing.
IF DIAPHRAGM IS NOT BEING REPLACED, SKIP STEPS 4
THRU 8
4. Remove diaphragm subassembly by sliding it away from the
valve body to disengage the lever arm (7).
5. Hold the lower diaphragm plate (5) and remove the screw
(6), separating the parts.
6. Clean the surfaces on the upper and lower diaphragm plates
that the diaphragm (3) seats against. Clean and degrease
the threads on the lower diaphragm plate and the screw.
(Degrease with Loctite primer T.)
7. Assemble the upper and lower diaphragm plates to the new
diaphragm with the screw. (Apply a few drops of Loctite #290
to the screw threads to lock the parts together.) The hole
through the lower diaphragm plate must align with any pair
of opposite holes in the diaphragm so that it will properly
engage the lever when reassembled into the valve.
8. Clean the flange surface on the diaphragm housing and re-
install the diaphragm subassembly onto the lever arm.
9. Clean the flange surface on the spring housing and install a
new gasket. The gasket may be temporarily held in place
using a few dabs of grease.
10. Set the spring housing on top of the diaphragm housing.
Using a 6” long screwdriver, or similar tool, reach through
the spring housing and push the diaphragm down to align
the diaphragm holes with the housings’ holes.
11. Drop the bolts into place and attach the lockwashers and
nuts, finger-right.
12. Continue to push the diaphragm down and snug-up the
bolts.
13. Evenly torque the bolts as described in the drawing, Figure
3.
14. Install the spring and adjusting screw. (Adjusting spring per
start-up instructions and replace cap.)
B. SEAT INSERT, PLUG, OR ASPIRATOR REPLACEMENT
CAUTION: WHEN REPLACING A PLUG OR SEAT INSERT,
THE LEVER MUST ALSO BE REPLACED TO INSURE SHUT-
OFF.
1. Remove all pressure from the line as outlined under WARNING.
2. Loosen the union nut (24) and separate the actuator from the
body.
MK608 only:
3a. Inspect the plug (11) and seat insert (26) to determine if
replacement is required. Replace if there are signs of wear
or uneven seating on either part.
4a. To replace the seat, simply unscrew it from the body using a
7/8" thinwall socket wrench. Install the new seat. An antiseize
compound applied to the threads will aid in future removal.
5a. To replace the plug or aspirator (12), disassemble the ac-
tuator as described in steps A2, A3, A4.
MK508 only:
3b. Remove the bottom cap (32) and gasket (33). Remove
retainer screw (34) and seat retainer (35) to determine if
replacement of the seat (26) or soft seat insert (36) is re-
quired. Replace if there are signs of wear or uneven seat
on either part.
4b. To replace the sat (26), simply unscrew it from the body
along with the o-ring (31) using a 7/8" thinwall socket wrench.
Install the new o-ring and seat. Apply antiseize compound
to the threads to aid in future removal. To replace the soft
seat insert, carefully remove it from the seat retainer with a
pocket knife and insert the new one in its place. Use of a
suitable rubber to metal adhesive is required.
5b. To replace the stem (11), or aspirator (12), disassemble the
actuator as described in steps A2, A3, and A4.
MK508/608:
6. Remove the two screws (9) fastening the lever arm bracket
(8) to the diaphragm housing and lift out the lever arm bracket
with the lever.
7. Inspect aspirating hole in aspirator to be sure it is clean.
Remove and replace aspirator if stem guide bores are worn.
Remove and replace plug.
8. Remove the screws from the lever arm bracket and clean the
threads. Degrease with Loctite Primer T. Also clean and
degrease the tapped holes in the diaphragm housing.
Possible Cause and Cure
• Oversizing causes cycling and hunting
and reduces the rangeability of the valve.
Make certain that your sizing is correct.
•
Attempting to exceed flow capacity.
Make certain that your sizing is correct.
•
Blocked vent line or vent passage in
spring housing. Clean.
•
Inlet pressure varying greatly. Stabilize or
use second regulator to control inlet
pressure closer.
•
Aspirator blocked. Clean.
• Orifice too large for inlet pressure.
• Improper spring.
• Diaphragm ruptured. Replace.
• Adjusting spring broken. Replace.
• Improper spring setting. Reset.
WARNING:
Be sure that there is no pressure in the valve before loos-
ening any fittings or joints. The following steps are recom-
mended:
1. Close the inlet shut-off valve, and by-pass valve.
2. Back off adjusting screw to allow inlet pressure to open
seats.
3. Allow pressure to bleed off through downstream piping.
4. When the inlet pressure gauge indicates no pressure
in the line, close the outlet shut-off valve.
Trouble Shooting
Trouble
Erratic
Control
Cannot Set
Outlet
Pressure
Will Not Operate