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GRADERS OPERATIONS WITH ZF POWER-SHIFT TRANSMISSION
GRADeRs OPeRATIONs WITH Zf POWeR-sHIfT TRANsMIssION 845b and 865b models with Zf Transmission
This machine is equipped with a 6-speed forward and 3-speed reverse power-shift transmission, with torque converter and “lock-up”.
CAUTION DURING sTART-UP Of THe eNGINe
A safety devise permits to start the engine with the transmission in Neutral position only, and with the parking brake applied. For additional information on engine starting, refer to “Engine Starting”.
CAUTION: Make sure the parking brake is applied by pressing on the lower part of the switch on the side panel. An indicator light glows on the front panel, indicating that the parking brake is applied.
ReLeAsING Of THe PARKING bRAK
CAUTION: Make sure that the parking brake is released before operating the machine. Due to the converter high multiplication torque, many times it is not possible to notice that the parking brake of the machine is applied. Should this happen, the transmission fluid and brake discs will overheat, as well as premature wear of the brake caliper pads will occur. A machine equipped with a torque converter will not present any engine brake when is parked. Make sure that parking brake is properly applied, if necessary install wheel blocks. With transmission in neutral position and the parking brake released, activate the service brakes to avoid the machine from moving.
Release the parking brake following the steps below: 1. The engine should be running and the service brake pressure at operational pressure. 2. The transmission control lever must be in neutral position. 3. Pull the lock backwards and press on the upper part of the parking brake switch, located on the lateral console panel. 4. Operate the machine by positioning the transmission control lever into forward (F) or reverse (R) position.
NOTes:
• If the engine is not running, the machine will remain braked, as the brake releasing is performed by the hydraulic pressure. • If the engine is stopped, without actuating the parking brake switch, the brake will be actuated automatically. In this case however, to start the engine again it will be necessary to actuate the parking brake switch to the “Braked” position.
PARKING BRAKE SWITCH
3
1 2
1. DECLUTCH SWITCH 2. TRANSMISSION MODE SWITCH 3. LOCK-UP SWITCH”
The transmission control system permits the operation of the transmission in the following two ways described below.
MANUAL Mode
For manual mode selection press the bottom part of the mode switch (2) of the transmission, on the side panel. On the front panel will appear the indication “M” within the gear symbol. On manual mode, the gear shifting will be performed through the selector lever. The transmission electronic control lever will prevent an improper gear shifting. The desired gear (1st , 2nd, etc) as well as the travel direction (forward or reverse) can be chosen through this selector lever. With the machine stopped, when the selector lever is moved (to forward or to rear position), the transmission automatically selects the 1st gear according to the chosen travel direction (1st forward or 1st reverse). The remaining gears selection can be performed by a simple touch to the right (speed increase) or to the left (speed decrease), on the selector lever. The digital display on the front panel will always indicate the direction and the gear in which the machine is operating. The selector lever can also select a gear for starting with the machine stopped. Move the selector lever 2 or 3 times to the right to select the second or third gear, and move it to forward (F) or to rear (R) and the transmission will engage the corresponding gear. CAUTION: If the parking brake or the service brakes are not activated the machine will start moving as soon as the selector lever is placed in the F or R position.
IMPORTANT: The transmission is equipped with a safety system that avoids, when the machine is stopped, a gear to be engaged with the engine speed over 1500 rpm. The purpose of this function is to protect the clutches against premature wear.
selection of upshifts
Shift gear normally, according to the machine’s speed, terrain inclination, and the ground traction conditions.
Downshifting
Downshift one gear at a time. Do not force the engine under 1700 rpm. Pay attention always to the tachometer and keep engine running at an appropriate range of rotations.
Gear shifting when going down a steep slope
During transportation, going down on very steep and short inclinations, the engine can be guided by the wheels of the grader. In order to maintain a high speed, it might be necessary to shift the gear and by using at the same time the service brakes, so that to avoid the engine overspeed. Normally, the most safe and recommended way is to go down a slope using a low gear, together with the service brakes application, especially for long distances.
shifting from forward to reverse gear and vice versa
The travel direction shifting must be performed with the machine stopped or at a very low speed, lower than the scheduled reverse limit. Over than the 4,0 km/h (2.5 mph) reverse limit and with the engine speed higher than 1600 rpm, the transmission control module will select automatically the neutral position and the machine will continue moving towards the same direction. On the other hand, when the speed is reduced below the scheduled limite, the new desired direction will be engaged.
AUTOMATIC Mode
For automatic mode selection press the lower part of the mode switch (3) of the transmission, on the side panel. A blue LED will turn on and the indication “A” will appear on the front panel within the gear symbol. The automatic mode can be used for transport as well as for operation. On automatic mode the transmission shifts gears automatically according to the speed and load in which the machine is submitted, not being necessary the operator’s interference for the appropriate gear selection. The transmission has an electronic control system that engages the selected gear only after the parking brake has been released. When releasing the parking brake maintain the service brakes pedal pressed down. Move the selector lever forward (F) or reverse (R) position, to select the desired travel direction. Release the service brake pedal, accelerate the engine and start work.
KICKDOWN SWITCH
The operator can cause the speed decrease in automatic mode, any moment he notices an unexpected increase of leveling load on, by just pressing the “kickdown” switch on the upper part of the gear shift lever. As soon as the leveling load is reduced, the transmission will shift automatically, selecting the appropriate gear for the work.
Lock-up
During extended leveling operations, or under conditions of excessive load on blade, press on the lower part of the “Lock-up” switch (2). The lock-up is a clutch that couples the engine directly to the transmission input, suppressing the torque converter action, avoiding thus the transmission fluid excessive heating, as well as the mechanical performance increase of the power train, providing more power for the wheels.
Declutch function
The declutch function is used to permit the engine to increase its rpm and supply additional hydraulic fluid to the implements in order to obtain a higher operation speed. Press the lower part of the declutch switch (1) and the brake pedal, to disengage the transmission. Release the brake pedal to engage again the transmission. NOTe: The declutch function is limited to gears 1, 2, 3 forward and 1, 2 reverse. Clutch gear reengagement is only possible with engine speed below 1500 rpm.
