TM 5-3820-256-10
(2)
Remove rust and corrosion as they appear and repaint affected surfaces.
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Power Take-Off/Hydraulic Pump.
a. Cold Weather Operation.
CAUTION
Use caution during entire warmup procedure. Run the truck engine at the slowest possible speed and
actuate all controls slowly.
CAUTION
The hydraulic oil provides lubrication to the hydraulic pump. When the oil in the suction line and
reservoir is too cold and stiff to flow easily, it cannot keep the pump inlet supplied with oil, thus cavitation
occurs. If this condition continues for more than a few moments, serious damage will result.
(1)
To prevent cavitation, "jog" the PTO/hydraulic pump on and off by depressing and releasing the clutch until
oil has warmed enough to permit adequate flow to the pump.
(2) If jogging the pump for 10 minutes does not produce acceptable results, do not attempt to operate the unit
until the vehicle can be taken inside a heated enclosure and serviced for cold weather operation. Refer to
the lubrication instructions in Chapter 3.
(3)
With adequate oil flow, continue to run pump until oil reservoir feels warm to the touch.
CAUTION
If, at any time, the sound of the pump changes from its usual "hum" to a "screaming" noise, stop the
pump immediately. The "screaming" indicates cavitation.
(4)
Resume jogging procedures until the pump can again be run continuously without cavitating.
b. High Humidity and/or Salt Water Conditions.
(1)
Protect painted or polished surfaces by keeping them well lubricated or coated with a thin layer of grease or
similar preservative.
(2)
Remove rust and corrosion as they appear and repaint affected surfaces.
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