PS Magazine - TB 43-PS-569
PS, The Preventative Maintenance Monthly
ISSUE 569
APRIL 2000
PS 569
3
APR 00
PS 569
2
APR 00
ontrary to what we printed on Page 3 of PS 539 (Oct 97), the presence of a
smoky mist coming from the air/hydraulic power unit when you raise or lower
the cab on your FMTV does
not
mean the gasket has failed.
A mist of hydraulic oil may come out of the power unit pump’s pneumatic
muffler at any time. You see the mist just like you see your breath on a cold day.
There’s nothing wrong.
The gasket between the oil reservoir and
the power unit is not under pressure. It just
keeps moisture and dirt from getting into the
reservoir.
If the gasket goes bad, and dirt and mois-
ture get into the reservoir, they could cause
pump seizure or clog the restrictors behind
the CAB TILT and SPARE TIRE valves. So
check the restrictors and gasket if the cab or
the spare tire bracket won’t go up or down.
hey look like washers, but they’re re-
ally fuses—and if they short out, you’ll
probably never know it until your
FMTV’s batteries run down.
They
are the fuse links under the 12-
and 24-volt DC cable connectors on the
FMTV’s alternator. Normally, when a
fuse link burns or shorts out, you won’t
have an electrical connection any more,
so you know something is wrong.
Not so with these fuse links. Depend-
ing on how they fail, you’ll have a con-
stant drain on the batteries, or the batter-
ies won’t charge. In either case, it’s bye-
bye batteries.
So remove those fuse links before they
cause problems. Here’s how:
1.
Turn the vehicle’s master switch off.
2.
Raise the cab.
3.
Disconnect the negative battery
cables.
4.
Remove the hardware on the 12-volt
DC power cable, discarding the self-
locking nut.
5.
Remove the fuse link and discard it.
6.
Reinstall the hardware, using a new
self-locking nut, NSN 5310-01-423-
0880.
7.
Remove the hardware on the 24-volt
DC power cable, discarding the old self-
locking nut.
8.
Remove the fuse link and replace it
with washer, NSN 5310-01-042-8391, so
the hardware won’t bottom out on the
stud. Discard the fuse link.
9.
Reinstall the hardware, using a new
self-locking nut like the one in Step 6.
Family of Medium Tactical Vehicles . . .
uh-oh!
that mist
doesn't
look good!
wait!
as long as the
cab
can still tilt
,
that mist is
ok
.
Smoky mist from here is OK
hoo-boy!
i feel a battery
drain
!
Remove fuse link
PS 569
3
APR 00
PS 569
2
APR 00
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