Dumping; Operation (Continued) - Komatsu 730E Operation & Maintenance Manual

Operation - Section 3
Page 3-8
1. Pull into dump area with extreme caution. Make sure area is clear of persons and obstructions, including over-
head utility lines. Obey signals directed by the spotter, if present.
Avoid unstable areas. Stay a safe distance from edge of dump area. Position truck on a solid, level surface
before dumping.
2. Carefully maneuver truck into dump position. When backing truck into dump position, use only the foot-oper-
ated brake pedal to stop and hold truck; DO NOT rely on Wheel Brake Lock to stop truck; this control is
unmodulated and applies REAR SERVICE BRAKES ONLY.
3. When truck is stopped and in dump position, apply Wheel Brake Lock and move the Selector Switch to the
"Neutral" position.
To Raise dump body:
the operator, and/or damage to the hoist cylinders, frame, and/or body hinge pins. If it is necessary to
dump this kind of material, refer to the CAUTION in the following procedure:
4. Pull the lever to the rear to actuate hoist circuit. (Releasing the lever anywhere during "hoist up" will place the
body in "hold" at that position.)
5. Raise engine RPM to accelerate hoist speed. Refer to the CAUTION below.
lever to "HOLD" position. If material does not continue moving and clear
body, repeat this procedure until material has cleared body.
6. Reduce engine RPM as last stage of hoist cylinder begins to extend and let
engine go to low idle as last stage reaches half-extension.
7. Release hoist lever as last stage of hoist cylinder reaches full extension.
To Lower Body:
(When dumping over a berm or into a crusher):
8. Move hoist lever forward to "down" position and release. Releasing the lever places hoist control valve in the
"float" position allowing the body to return to frame.
NOTE: If dumped material builds up at the rear of the body and the body cannot be lowered, perform steps "a" &
"b" below:
a. Move hoist lever back to the "hoist" position to fully raise the dump body. Then release the hoist lever so it
returns to the "hold" position.
NOTE: DO NOT drive forward if the tail of body will not clear the crusher wall in the fully raised position.
b. Shift Selector Switch to "Forward", release Brake Lock, depress Override button and drive forward to clear
the material. Stop, shift Selector Switch to "Neutral", apply Brake Lock and lower body again.

DUMPING

As body raises, the truck Center of Gravity (CG) will move. Truck must be
on level surface to prevent tipping / rolling!
The dumping of very large rocks (10% of payload, or greater) or sticky mate-
rial (loads that do not flow freely from the body) may allow the material to
move too fast and cause the body to move RAPIDLY and SUDDENLY. This
sudden movement may jolt the truck violently and cause possible injury to
If dumping very large rocks or sticky mate-
rial as described in WARNING above, slowly
accelerate engine RPM to raise body. When
the material starts to move, release hoist
OM3035.1 02/03
Operating Instructions