Series 1250 Pneumatic Chemical Injection Pump
Operating Manual
Page 14 of 19
Packing which is non-adjustable, such as Part Number VXXX-2LXL Uniseal packing, must be replaced
as soon as it begins to leak. To function properly, this style of packing should always be held in place
with the packing nut fully engaged. This style packing is now discontinued.
The 3/16”, 1/4”, and 3/8” plunger sizes require a metal adapter sleeve in the packing gland. When
removing the packing, this sleeve should also be removed and cleaned. It is important to remember
to re-install the sleeve prior to installing the new set of packing. 1/8” plunger sizes containing serial
numbers AB056731 (B Model) and AG057154 (GR Model) and earlier serial numbers require a sleeve.
The 3/16” plunger size also require an O-ring, a backup ring, and a snap ring. Please refer to the
drawings at the end of this Guide. If your early model 1/8” Series 1250 does not have a new-style
large sleeve with a backup ring, O-ring, and snap ring, please contact CheckPoint to obtain the
updated parts. 1/8” plunger sizes containing serial numbers AB056731 (B Model) and AG057154 (GR
Model) and earlier serial numbers require a O-ring, a back-up ring, and a snap ring.
5.1 Packing Adjustment
Packing adjustment is usually indicated whenever adjustable packing is installed in the pump and leakage can be
observed around the packing nut or coming out of the weep hole drilled through the packing nut. In most cases, if
there is no leakage, no adjustment is necessary.
5.1.1 Use a CheckPoint T55-101 packing adjuster, which is specifically designed for this purpose. If one is not
available, you may order one at no charge directly from CheckPoint. In an emergency or if time is short, a 6” length
of ¼” OD tubing or metal rod may be used.
5.1.2 It is highly recommended that the packing is adjusted while the pump is not running.
5.1.3 To tighten the packing, insert the tool into one of the six shallow radial holes in the packing nut, and tighten
the nut clockwise (when looking at the pump from above) or from right to left (when viewing the pump from the
side while it is in a vertical position). Snug the nut until light pressure with one finger on the packing nut tool no
longer moves the packing nut.
5.1.4 From this point, TIGHTEN THE NUT 1/6 TURN ONLY (there are six holes, so each 1/6 turn moves the next hole
into the position of the previous one):
5.1.5 If adjusting the packing prior to new installation or when not currently running, tighten the nut 1/6 turn from
the finger tight position.
5.1.6 If adjusting the packing while pump is operating, pause after each 1/6 turn to determine if the leakage has
stopped, allowing for enough time to ensure previous leakage has already drained from the nut weep holes and
threads. If pump is still leaking, turn packing nut an additional 1/6 turn and check again. Continue turning the nut
1/6 turn at a time as often as necessary to stop the leakage. If the leakage cannot be stopped, or if excessive force
is required to stop leakage, it is time to replace the packing.
5.2 Packing Replacement
Follow the steps below to change the packing in your Series 1250.
CP/MAN-PRD-015 REV. 15 EFF. DATE: 07/08/2022
