Doc. #: A-718C, Rev. 1
Page 17 of 36
5.1.7.1 At this point, remove the seat insert (item 31) from the body
(item 4). The seat insert will be held in place by pressure exerted
by the two (2) O-rings (item 33). One possible option to assist
in the removal of the seat insert is by placing a circular piece of
hardwood or plastic on top of the seat insert on the inside of the
body through the outlet hole. Once this block of wood or plastic
is in place, insert a 3/4" diameter plastic or aluminum rod
through the top of the body until it contact the block of
wood/plastic sitting inside the body, resting against the seat
insert. Once contact is made, using a hammer or mallet, lightly
tap the top portion of the rod until the insert is pushed out of the
body. Handle the insert with care, as this is where the crowned
seat is located.
ATTENTION
: Do not use a steel block to assist in the
removal of the seat insert as it might nick or damage the top surface of the insert. Additionally,
ensure that the body assembly is supported by the body flange outer edges, as so when the insert
is being pushed out it can come out easily with its path being obstructed.
ATTENTION
: The seat insert is not threaded into the body; it is held in place only by the
compressive force of two (2) O-rings. Do not place the bottom of the insert in a vise to assist in
removing it as it may deform the tongue and gasket surfaces, which are machined to a close
tolerance to fit into the groove in the cover plate.
5.1.8 Use a 1-1/16" open-end wrench to unscrew the packing screw (see Figure 5-5). Then remove the hand
wheel nut and washer (items 13 and 25, respectively). Using the hand wheel, screw the stem down through
the bonnet as far as it can go. It should be possible, gripping by hand on the retainer end of the stem, to
screw it all the way out of the bonnet. If it binds on the last threads, put the retainer end of the stem into the
vise, gripping it lightly and proceed to back the bonnet off from the stem.
Figure 5-14 Remove Nut and Washer
Figure 5-15 Lower the Stem
Figure 5-13 Remove Seat Insert
