Maintainers, note that there are updated maintenance procedures for the M109A6 and M109A7 howitzers’ variable recoil and variable recoil housing.
M109A6 Changes
Maintainers will no longer conduct tasks for Item 1, Variable Recoil Housing, and Item 2, Variable Recoil, as they currently appear in the semi-annual PMCS tables in TM 9-2350-314-13&P (Dec 14).
These tasks have been rewritten with changes to the steps and NMC criteria for checking the recoil sector gear. The elevations at which the sector gear should stop moving has changed to 622 mils for long recoil and 978 mils for short recoil.
A maximum allowable gap of 1/16th inch between the sector gear and stop, measured at 622 mils and 978 mils, has been incorporated and will be measured using the machinist's rule, NSN 5210-00-600-5757, from the Forward Repair System (FRS). These tasks will be conducted as part of the annual PMCS requirements.
See the changes to the annual PMCS requirements
HERE
M109A7 Changes
Maintainers will no longer conduct the task for Item 9, Variable Recoil and Variable Recoil Housing, as it currently appears in the quarterly PMCS tables of TM 9-2350-401-23&P (Nov 20).
This task has been rewritten with changes to the steps and NMC criteria for checking the recoil sector gear. The elevations at which the sector gear should stop moving has changed to 622 mils for long recoil and 978 mils for short recoil.
A maximum allowable gap of 1/16th inch between the sector gear and stop, measured at 622 mils and 978 mils, has been incorporated and will be measured using the machinist's rule, NSN 5210-00-600-5757, from the Forward Repair System (FRS).
This task will be conducted as part of the semi-annual and annual PMCS requirements. See the semi-annual PMCS requirement change
HERE and the annual PMCS requirement change
HERE.
For more information, check out TACOM Maintenance Action Message 22-038
HERE.