Komatsu Galeo HD405-7R, Operation & Maintenance Manual

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OPERATION
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.
WARNING
When the machine stops, put blocks under the tires immediately.
For details of the maximum permitted speed when traveling downhill with the retarder operated, see the brake performance
graph for the downhill distance and grade.
It is dangerous if the machine travels downhill at a speed greater than the maximum permitted speed on the brake performance
graph. This may damage the retarder brake.
If the retarder oil temperature caution lamp on the machine monitor lights up when the retarder is being used to travel downhill,
shift the transmission down.
(When the caution lamp lights up, the central warning lamp also 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, return the gear shift lever
to the Neutral position, run the engine at 2000 rpm, and wait for the caution lamp to go out.
If the retarder stops having any effect when the machine is traveling downhill with the retarder operated, do as follows.
1. Release the retarder control lever fully, then operate the retarder control lever again.
2. If the retarder still does not work even when the retarder control lever is operated again, release the retarder control lever fully.
Then depress the brake pedal, stop the machine, and ask your Komatsu distributor to carry out repairs.
Operate the retarder gradually. If it is operated suddenly, there is danger that the tires may 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
When traveling downhill, operate the retarder control lever. This makes it possible to shift down more quickly than for normal
deceleration. In addition, it is also possible to travel without shifting up.
When traveling downhill, do not use the foot brake except in emergencies. Using the foot brake will cause the front brake to
overheat and will reduce the service life.
Do not accelerate or shift up while operating 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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