Traveling Downhill - Komatsu GALEO HM350-2 Operation & Maintenance Manual

OPERATION

TRAVELING DOWNHILL

When traveling downhill, travel at a safe speed which matches the width of the road, the condition of the road
surface, and other conditions of the jobsite.
When the machine stops, put blocks under the tires immediately.
For the maximum permissible speed when traveling downhill using the retarder, see the brake performance graph for the
downhill distance and grade. Traveling continuously downhill at a speed greater than the maximum permitted speed on the
brake performance graph is dangerous as the retarder brake may be damaged.
If the retarder oil temperature caution lamp on the machine monitor lights up when the retarder is being used, shift down to
travel downhill. (When this happens, the central warning lamp lights up and the alarm buzzer sounds.)
If the caution lamp does not go out even when the transmission is shifted down, stop the machine immediately, set the shift
lever to the N position, run the engine at 1800 rpm, and wait for the caution lamp to go out.
If the retarder loses its effect when it is used for traveling downhill, do as follows.
1. Release the retarder control lever completely, then operate the retarder control lever again.
2. If the retarder still has no effect even when the retarder control lever is operated again, return the retarder control lever
completely to the released position, then depress the brake pedal to stop the machine, and contact your Komatsu distributor
for repairs.
Operate the retarder slowly. If the brake is applied suddenly, there is danger that the tires will slip.
Do not move the gear shift lever to the N position when the machine is traveling or when it is traveling down a slope. Always
place the transmission in gear before traveling.
o If the transmission is in Neutral, the engine cannot provide any braking effect and the steering wheel will become heavier.
In addition, there will be lack of cooling oil for the retarder, so there is danger that it will overheat or that the actuation of the
brake will be poor.
o There may also be damage to the transmission or other parts of the power train, and there is danger of unexpected accidents.
NOTICE
If the retarder control lever is operated when traveling downhill, the transmission can be shifted down sooner than with normal
deceleration. It is also possible to travel without shifting up.
Do not accelerate or shift up when using the retarder. The engine speed will rise and this may cause the alarm buzzer to sound
and the central warning lamp to flash.
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WARNING
OPERATION