621G Wheel Tractor-Scraper Towing the Machine Caterpillar


Towing the Machine
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1.1. Running Engine
2.1. Stopped Engine

------ WARNING! ------

Personal injury or death could result when towing a disabled machine incorrectly.

Block the machine to prevent movement before releasing the brakes. The machine can roll free if it is not blocked.

Follow the recommendations below, to properly perform the towing procedure.


------ WARNING! ------

Personal injury or death can result from a brake malfunction.

Make sure all necessary repairs and adjustments have been made before a machine, that has been towed to a service area, is put back into operation.


------ WARNING! ------

Personal injury or death can result from a machine moving during driveshaft removal and installation.

Block the wheels securely so that the machine cannot move.

The towing connection must be rigid, or towing must be done by two machines of the same size or larger than the towed machine. Connect a machine on each end of the towed machine.


This machine is equipped with a parking brake that is spring-applied and air pressure released. If the engine or the system for pressure air is inoperable, the parking brake is applied and the machine cannot be moved.

These towing instructions are for moving a disabled machine for a short distance at low speed. Move the machine at a speed of 2 km/h (1.2 mph) or less to a convenient location for repair. Always haul the machine if long distance moving is required.

This machine can be towed by removing the drive shaft from the machine. Refer to the machine's Service Manual or consult your AVSpare dealer for the removal procedure for the drive shaft and for the installation procedure for the drive shaft.

Shields must be provided on both machines. This will protect the operator if the tow line or the tow bar breaks.

Do not allow an operator to be on the machine that is being towed unless the operator can control the steering and/or the braking.

Before you tow the machine, make sure that the tow line or the tow bar is in good condition. Make sure that the tow line or the tow bar has enough strength for the towing procedure that is involved. The strength of the tow line or of the tow bar should be at least 150 percent of the gross weight of the towing machine. This requirement is for a disabled machine that is stuck in the mud and for towing on a grade.

Only attach the tow line to the towing eyes on the frame, if equipped.

Do not use a chain for pulling a disabled machine. A chain link can break. This may cause personal injury. Use a wire cable with ends that have loops or rings. Put an observer in a safe position in order to watch the pulling procedure. The observer can stop the procedure if the wire cable starts to break. Stop pulling whenever the towing machine moves without moving the towed machine.

Keep the tow line angle to a minimum. Do not exceed a 30 degree angle from the straight ahead position.

Quick machine movement could overload the tow line or the tow bar. This could cause the tow line or the tow bar to break. Gradual, steady machine movement will be more effective.

Normally, the towing machine should be as large as the disabled machine. Make sure that the towing machine has enough brake capacity, enough weight, and enough power. The towing machine must be able to control both machines for the grade that is involved and for the distance that is involved.

You must provide sufficient control and sufficient braking when you are moving a disabled machine downhill. This may require a larger towing machine or additional machines that are connected to the rear of the disabled machine. This will prevent the machine from moving out of control downhill.

All situation requirements cannot be listed. Minimal towing machine capacity is required on smooth, level surfaces. Maximum towing machine capacity is required on inclines or on surfaces in poor condition.

When any towed machine is loaded, the machine must be equipped with a brake system that is operable from the cab.

Consult your AVSpare dealer for the equipment that is necessary for towing a disabled machine.

Running Engine

If the engine is running, the machine can be towed for a short distance under certain conditions. The transmission and the steering system must be operable. Tow the machine for a short distance only. For example, pull the machine out of mud or pull the machine to the side of the road.

The operator on the towed machine must steer the machine in the direction of the tow line.

Carefully obey all of the instructions that are outlined in this topic.

  1. Move the transmission control (lever) to the NEUTRAL position.

  2. Raise the attachments off the ground.

Stopped Engine

Perform the following steps before you tow the machine:



Illustration 1g01958744


Illustration 2g01958745

  1. Disconnect steering hose (1) and disconnect steering hose (2). Cap the steering hose connections. Connect steering hose (1) and steering hose (2) with a union and two seal O-rings.


    NOTICE

    Be sure the cylinder hoses are connected correctly before operating the machine. With the hoses reversed, the steering system will not function.


  2. If failure of the internal transmission or of the drive line is suspected, remove the drive shaft.

    For the removal procedures for the drive shaft and the installation procedures for the drive shaft, consult your AVSpare dealer or refer to the Service Manual.

  3. Release the parking brake.


    NOTICE

    Release the parking brake to prevent excessive wear and damage to the parking brake system, when towing without brake air pressure.

    The procedure for manual release of the parking brake is outlined in the Operation and Maintenance Manual, "Parking Brake Manual Release".


  4. Inspect the machine for power train damage. If damage is suspected, remove the axle shafts.

  5. Fasten the tow bar.

  6. Remove the wheel blocks. Tow the machine slowly. Do not exceed 2 km/h (1.2 mph).