EDGE-CUTTING 8V6274 - Caterpillar

Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat® products.Dispose of all fluids according to local regulations and mandates.
Park the machine on a level surface. Move the parking brake control to the ENGAGED position and shut off the engine. Install the steering frame lock. Refer to Operation and Maintenance Manual, "Steering Frame Lock".Remove the steering frame lock once the ejector control valve has been tested and the machine is in working order.Test the Stem for Binding
Relieve the system pressure. Refer to Systems Operation, Testing and Adjusting, "General Information".
Illustration 1 g03779591
The ejector control valve is located above the steering cylinder on the left side of the machine.
(3) Ejector control valve
(3a) Pilot control actuator
(3b) Pilot control actuator
Remove pilot control actuator (3a) and pilot control actuator (3b). The pilot control actuators are located at either side of body (3) of the ejector control valve. Refer to Disassembly and Assembly, "Control Valve (Ejector) - Disassemble".
Check if the stem will slide in the body of the ejector control valve. Remove the stem and check for excessive wear or scoring. Also check for contamination in the ejector control valve.
Remove any contamination from the ejector control valve and from the stem.
If the stem does not slide inside the ejector control valve or if the stem is damaged, the ejector control valve must be serviced. Test the Proportional Solenoids
Illustration 2 g03779592
The ejector control valve is located above the steering cylinder on the left side of the machine.
(3) Ejector control valve
(3a) Pilot control actuator
(3b) Pilot control actuator
Disconnect the wiring harness to the suspected proportional solenoid. Check the resistance between the two pins on the proportional solenoid. The resistance should be 5 0.3 Ohms at 25 °C (77 °F). If the resistance is not 5 0.3 Ohms, replace the proportional solenoid. Refer to Disassembly and Assembly for information on the ejector control valve.If the resistance is 5 0.3 Ohms, proceed to step 2.
Momentarily connect the proportional solenoid to the battery (24 V) and listen for movement of the core of the proportional solenoid. Do not maintain the connection to the battery (24 V) for more than 0.5 second. If the core does not move, replace the proportional solenoid. Refer to Disassembly and Assembly for information on the ejector control valve.
Install any components which were removed from the machine.