PS Magazine - TB 43-PS-564
PS, The Preventative Maintenance Monthly
ISSUE 564
NOVEMBER 1999
PS 564
26
NOV 99
O
perators, your dump truck’s hydraulic cylinders leak. Some leak just a dab,
others a bit more. But don’t call your mechanic—the cylinders are supposed to
leak.
The single ram cylinders on all M929/M930 dump trucks seep just enough to
keep the rod coated with oil and the seal wet. The oil protects the rod from the
elements and corrosion.
Telescoping hydraulic cylinders—like the hoist cylinders on M917 and F5070
dump trucks—have seals at each segment of the cylinder. Each seal seeps a bit to
lube the seal and coat the cylinder. The seepage adds up—as much as a quart a
day. But, this type of leakage does not make
your truck NMC.
If the hoist cylinder will raise the empty
body, your truck’s OK.
Check the fluid level daily. If it takes more
than a quart a day to refill the reservoir, get
your mechanic to look things over.
Dump Trucks . . .
Oil Seepage Protects Cylinders
perators, before you head out to the work site, eyeball the clamps holding
together your scoop loader’s brake actuator air chambers.
The retaining bolts and nuts vibrate loose. When that happens, air leaks from
the chamber. No air means no brakes.
So, grab the clamp to see if it’s loose. If it is, get your mechanic to torque the
nuts to 70–80 lb-ft. Between scheduled 250-hr services, look for loose nuts,
shiny spots or rust around the bolt
heads and nuts on
both
the front
and rear air chambers. If you spot
any, report them to your mechanic.
MW24C Scoop Loader . . .
Clamp loose?
Oil protects cylinder rod
i should've
checked
those
brake
clamps
!
PS 564
26
NOV 99
Back to Top Back to Top
