PS Magazine - TB 43-PS-713
PS, The Preventative Maintenance Monthly
ISSUE 713
APRIL 2012
8
PS 713
APR 12
9
PS 713
± Here’s±the±way±we±lube±the±lead±screw:
1.
±Raise±the±cannon±tube±to±its±maximum±elevation.
2.
±Loosen±the±clamp±attached±to±the±back±of±the±elevation±gearbox±and±
slide±back±the±boot.
3.
±Clean±off±all±the±old±grease±and±
dirt.±Then±apply±fresh±WTR±grease±
to±the±elevation±lead±screw.±NSN±
9150-00-944-8953±brings±a±1±
3/4-lb±can±of±WTR.
4.
±Reinstall±the±boot,±then±check±
it±carefully±to±make±sure±it±didn’t±
rip±or±tear.±A±damaged±boot±lets±
in±moisture±that±will±wash±away±
the±WTR±and±quickly±rust±the±lead±
screw.±A±replacement±boot±comes±
with±NSN±5342-01-571-9453.
5.
±Fully±depress±the±cannon±tube.
6.
±Lower±the±undercradle±electronics±assembly±(belly±pan)±located±under±the±
cradle.±Inside±you’ll±find±the±lead±screw±cover.
7.
±Open±the±cover±to±access±the±lead±screw.±Clean±the±exposed±portion±of±
the±screw±and±apply±new±WTR.±If±the±gasket±on±the±lead±screw±cover±shows±
no±damage,±you±can±reuse±it±until±a±new±one±is±available.±Install±a±new±gasket±
from±the±elevation±gearbox±screw±seal±kit,±NSN±1090-99-282-2448.
8.
±Close±the±lead±screw±cover±and±secure±the±belly±pan±back±in±place.
9.
±Fully±depress±and±elevate±the±cannon±tube±a±few±times.±That±will±ensure±
the±entire±length±of±the±lead±screw±is±properly±lubed.
Dear±Editor,
± The±importance±of±lubing±the±elevation±gearbox’s±lead±screw±during±
quarterly±services±
cannot±be±
overstated.±If±the±
lead±screw±is±left±
unlubed±or±only±partly±
lubed,±it±will±rust±and±
the±cylindrical±nut±
seizes±in±place.
± Repairing±the±
damage±is±a±very±
expensive±and±time-
consuming±process.±
It±means±removing±
the±cannon±tube,±
cradle±and±possibly±
even±replacing±the±
elevation±gear±box.
CW3±Robert±M.±Goldsmith
Ft±Carson,±CO
Rick±Banning
Ft±Sill,±OK
Curtis±Bradley
Ft±Bragg,±NC
CW3±Brent±Wacasey
Ft±Sill,±OK
Editor’s note:
Excellent work,
gentlemen!
Keeping that rust
at bay will save
units a lot of time
and money later.
M777A2 Towed Howitzer…
A Little
lube
Now
Beats a
Lotta
RUST
Lat
er!
Without lube, lead screw and nut will rust
Check boot for damage after reinstalling
Lower belly pan to access lead screw cover
how’re
you doing
today,
rusty?
I told
you
not
to call
me that!
it wasn’t
my fault
that
no one
lubed my
elevation
gearbox
lead screw!
713 08-09.indd
1-2
3/7/12
5:30 PM
Click here for a copy of this article to save or email.
Back to Top Back to Top
