WARNING:
Installation, disassembly, repair and maintenance
must be performed only by qualified personnel.
All gas MUST be evacuated from the system before starting repairs.
Installation, usage and maintenance of this product must be in
compliance with all RegO
®
instructions as well as requirements
and provisions of NFPA #54, NFPA #58, DOT, ANSI, all applicable
federal, state, provincial and local standards, codes, regulations
and laws.
Inspection and maintenance on a periodic basis is essential.
Be sure all instructions are read and understood before installation,
operation and maintenance. These instructions must be passed
along to the end user of the product.
CAUTION:
Contact or inhalation of liquid propane, ammonia and
their vapors can cause serious injury or death! NH
3
and LP-Gas
must be released outdoors in air currents that will insure disper-
sion to prevent exposure to people and livestock. LP-Gas must be
kept far enough from any open flame or other source of ignition to
prevent fire or explosion! LP-Gas is heavier than air and may not
disperse or evaporate rapidly if released in still air.
Disassembly and Repair Procedure
CAUTION: READ THROUGH ALL OF THESE INSTRUCTIONS, IN-
CLUDING THE NOTICE AND WARNINGS ON THE BACK OF THIS
SHEET, BEFORE BEGINNING ANY DISASSEMBLY OR REPAIR.
NOTE: Repairs must be performed in a clean area. Hands, cloth-
ing, tools and work area must be completely free of oil, grease
and foreign matter to prevent contamination of component parts
and valves.
A. Disassembly
1.
EVACUATE ALL GAS FROM THE SYSTEM BEFORE ANY DIS-
ASSEMBLY OR REPAIR. Turn handwheel counterclockwise as
far as it will go to release any gas remaining in the container.
CAUTION: Do not apply force after valve is fully open.
2.
Using a 13/16" wrench, remove four cap screws from bonnet by
turning counterclockwise. Remove bonnet assembly from valve
body.
3.
Remove body gasket and discard.
To Install New Seat Disc:
4.
Clamp the square section of bonnet in a vise.
Figure 1
– TA7894P
5.
Use wrench flats on the seat disc retainer to secure while using
a 1-5/16" wrench, use another wrench to remove the seat disc
retainer nut.
6.
Remove and discard seat disc. Install a new one by pressing into
recess of seat disc retainer as shown in Figure 2.
7.
Apply Loctite 271
®
thread locking compound to the first three
threads of seat disc retainer.
CAUTION: Do not allow Loctite to contact seat disc.
8.
Thread on disc retaining nut and tighten with a wrench to 240-
270 in-lbs torque. Stake nut in two places at retainer threads
(See Figure 2) to prevent loosening.
NOTE: If no further repairs are required, disregard steps A-9 through A-14
and B-1 through B-9 of the instructions. Finish reassembly by following
steps B-10 through B-15 only. TO INSTALL ALL OF THE TA7894-50
REPAIR PARTS, FOLLOW ALL OF THE REMAINING INSTRUCTIONS.
9.
Remove handwheel locknut by turning counterclockwise with a
small wrench to allow removal of washer, information disc and
handwheel.
10. Using a 1- 3/8" wrench with a handle of sufficient length to develop a
minimum of 1000 in-lbs torque, turn seal housing counterclockwise
and carefully remove from bonnet.
CAUTION: Do not mar finish of stem.
11. Remove and discard pressure seal rings and o-ring from seal hous-
ing.
12. Using a small wrench on the square section, screw the stem down
and out through the bottom of bonnet by turning clockwise (as
viewed from top).
CAUTION: If stem** is scratched or scored, a new one must be
installed.
13. Remove and discard seal housing gasket, washer and jam ring
from bonnet. Save spring for reassembly.
14. Inspect stem** threads and mating threads in bonnet**. If any
Locknut
Information Disc
Washer
Handwheel
Seal Housing
O-Ring*
Pressure Seal Rings (2)*
Jam Ring*
Washer*
Gasket*
Spring
Cap Screw (4)
Bonnet
Body Gasket*
Plug
Stem
Stem Holder
Stem Retainer (2)
Seat Disc Retainer
Seat Disc*
Flange Gasket*
Cap Screw (8)
Seat Disc Retainer Nut*
Body
* These items are included in the TA7894-50 assembly,
recommended for most repairs.
** Must be ordered separately from RegO
®
.
TA7894-50 Repair Kit For
TA7894P Tank Car Valves
Apply minimum 540±25 in-lbs torque using a tight-
ening sequence of alternating bolts in a crisscross
pattern.
Figure 3
Bonnet Flange Cap Screw
Tightening Sequence
1 - 3 - 2 - 4
stake here
Seat Disc
Retainer
Seat Disc*
Seat Disc
Retainer Nut
Figure 2 -
Seat Disc and Retainer Assembly
1- 5/16"
Wrench Flats
