limit, not merely suggested. With the PTO being driven at approximately 3 times engine speed, any PTO and pump
overspeeding will damage these components. With the PTO mounted at the eleven o'clock position on the transmission,
overspeeding damage to the PTO usually will require an overhaul to a very expensive automatic transmission, that would
otherwise last the life of the truck. Carefully watch the tach and get use to the 1500 RPM engine sound limit.
h. When operating in cold weather, usually defined as colder than 400F, let the PTO and hoist pump circulate the oil
with the engine at or a little above idle RPM to ease the load on the hoist hydraulic system and to warm up the system.
Leave the hoist control valve in neutral during warm up and don't race the engine.
i. Upon completion of hoist operation always move the hoist control to neutral and lock it. Most important, switch
the PTO air control valve to "OFF', disengaging the PTO drive. Never transport away from the dumping site or travel
down the road with the PTO engaged.
3. Adherence to the operation in 2 above is intended to ease the shock loading of PTO engagement and reduce PTO
drive shaft breakage. Operator impatience, over a period of time; is the indirect cause of hoist drive shaft breakage. In
the CCE-IHC dump truck, the PTO driven gears have a mechanical connection to the pump all of the time. There is no
gradual application of power. Upon PTO engagement and upon rotation of the transmission gear train, the hoist pump
must either turn or some part of its drive train fail. The PTO shaft breakage factors are as follows:
a. "PTO tooth-to-tooth gear hanging" and subsequent slamming engagement, when gears begin to rotate (brakes
released or transmission shifted into neutral) .
b.
PTO overspeed as a result of operation in the range of from 1500 to 2100 RPM engine speed.
c.
PTO engagement on the run (at any speed) without benefit of stopping the transmission drive gear rotation.
d.
Cold starting of the hydraulic pump having the hydraulic oil partially solidified from the cold weather.
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