5373 Air Activated Tube Tester
7
OPERATING INSTRUCTIONS (CONT.)
Installing Replacement Seals:
Replacement seals for the 5373 guns are supplied with the corresponding size washers. Always
replace the seals and washers on both guns at the same time. (See chart on page 9 for seal selection.)
1. Remove the locknut (1) from the end of the support tube (4) and set it aside.
2. Remove the Seal and Washer Set (2) from the support tube (4). Discard if worn. Under optimum testing
conditions you should be able to test between 100 to 500 tubes per replacement Seal and Washer Set.
3. For replacement Seal and Washer sets of the same size, install on existing support tube (4). If you are
changing the Seal and Washer set to a different size, keep in mind that the support tube assembly
(5) may be required to change as well. To replace the support tube assembly, refer to the procedure
outlined below.
4. When replacing the locknut (1) on the support tube (4) do not use a wrench, screw it on finger tight
only. A small space between the locknut, seal and washer set, and back-up washers is normal.
There will be enough stroke in the air cylinder to compensate for this space.
Replacing the Support Tube Assembly:
The 5373 test guns are originally shipped with three sets of support tube assemblies (5). These
support tube assemblies will allow you to test tubes with ID’s from 0.28” to 0.48”, 0.49” to 0.83” and
0.84” to 1.23” (7.1mm to 12.3mm, 12.4mm to 21.2mm, and 21.3mm to 31.3mm respectively).
1. Remove the Seal and Washer Sets (2) as outlined above.
2. Using an open end wrench on the wrench flats provided on the piston and a pipe wrench on the
support tube (4) gently unscrew the support tube from the piston inside the cylinder.
3. Choose the correct size support tubes for the tube ID being tested. All three sizes of support tubes will
fit into the piston of the test gun. Use Never-seize or similar product to lubricate and seal the threads.
Do not over tighten the support tube.
4. Repeat steps 1 thru 3 for the remaining gun.
5. If testing tube ID’s from 0.28” to 0.48” (7.1mm to 12.3mm) thread the regulator assembly with arrow
pointing towards gun onto reducing nipple leak tight.
6. Prior to replacing the Seal and Washer Set (2) and the Back-up Washer Set (3) inspect the support
tube for scars left from the replacement procedure. File smooth if present.
Other Replacements and Repairs:
Under no conditions should you attempt to service the air cylinders. Any attempt to perform service
on the cylinders may void any and all remaining warranties, implied or otherwise.
