2-3. Exercising Equilibrators.
a. General. Pneumatic and hydropneumatic equilibrators must be exercised periodically for reasons given in
paragraph 1-3. Proper exercising of equilibrators at least every six months, as outlined in paragraph 2-3b below, is
essential to maintain them in serviceable condition.
b. Angled Equilibrators. To exercise equilibrators mounted on a carriage or vehicle, elevate and depress the
cannon at least three times.
c. Equilibrated Elevating Cylinders (Howitzer M109 Series).
(1) To exercise the equilibrated elevating cylinders on the howitzer M109 series, activate the cab hydraulic
system and elevate and depress the cannon through its full range at least three times.
(2) If it is not practical to activate the cab hydraulic system, use the elevation hand pump and elevate and
depress the cannon through its full range at least once.
2-4. Exercising Unmounted Hydropneumatic Recoil Mechanisms and Equilibrators In Storage.
a. General. The procedures given in the preceding paragraphs apply to hydropneumatic type recoil mechanisms or
equilibrators in storage. When exercising has been completed, restore proper preservatives in accordance with MIL-P-
14232 and pertinent Packaging and Data Sheets. Record the date of exercising on a tag and attach to recoil mechanism
b. Unmounted Hydropneumatic Recoil Mechanisms. If the hydropneumatic recoil mechanism is of the
independent type and unmounted, it will be necessary to exercise the recoil cylinder assembly and counterrecoil assembly
separately. The force required to exercise the recoil cylinder assembly is only that force necessary to overcome friction.
Extension of 6 inches will be enough for the recoil cylinder and counterrecoil assembly. An adapter may be improvised for
extending and retracting the recoil piston by a direct pull or a jacking process. The counter recoil assembly will return to a
retracted position on its own volition due to nitrogen pressure. Recoil mechanisms may also be exercised with 7 1/2
horsepower portable gymnasticator (RIA drawing E7113950) and pertinent adapters as follows:
Adapter D7123504 (RIA drawing (for M1 series recoil mechanisms)
Adapter D7123508 (RIA drawing (for M2 series recoil mechanisms)
Adapter D7123510 (RIA drawing (for M6 series recoil mechanisms)
Adapter D7123512 (RIA drawing (for M4 series recoil mechanisms)
c. Equilibrators. Equilibrators in storage may or may not contain high nitrogen pressure. Equilibrators may be
exercised by anchoring one end to the floor or wall and pulling the other end with a suitable power source. Extend the
equilibrators 8 inches.