Usage:
120H (6TM, 4MK, 6NM, 5FM, 9YR, 2AN, 9FN, 3GR),
120K (JAP, SZN),
120K2 (SZS),
135H (7MM, 3YK, 8WN),
12H (5ZM, 4XM, 2LR, 4ER, 8MN, 2GS, 2WR),
12K (JJA, SZP),
140H (8JM, 2ZK, 8KM, 5HM, 9TN, 3AS, 9ZN, 3FR),
140K (JPA, SZL),
140K2 (SZW),
143H (1AL),
160H (9JM, 9EJ, 6WM, 2FM, 3GM, 2HS, 3HR),
160K (JBP, SZM),
163H (5AK),
14H (7WJ),
16H (6ZJ, 3JR) 24H (7KK) Motor Graders
This service magazine article provides the necessary information for relocating and installing additional implement control valves on H-Series Motor Graders.
Illustrations in this article may look different from your machine. While the illustrations are typical, the number of valves may differ depending on your application.
Do not perform any procedure, outlined in this article, or order any parts until you read and understand the information contained within.
The H-Series Proportional, Priority, Pressure-Compensated system (PPPC) delivers better and more efficient flow proportioning to multiple circuits.
The PPPC load-sensing system provides hydraulic power on demand, consuming power only when needed. The new H-Series control valves proportion flow to the circle motor and cylinders through the use of an internal flow compensator.
The implement control valves are designed and built by Caterpillar specifically for motor graders. Lock valves are now built into all control valves, which maintain exact cylinder positioning. Line relief valves are incorporated into blade tip, blade sideshift, both blade lift control valves, ripper, scarifier, plow dozer, dozer angle, and wing. They protect the cylinders from over-pressurization.
The smaller H-Series control valves permit the installation of up to 14 direct-acting control valves (seven per side ) on the control console. A 15th control valve may be added with the use of a solenoid control valve.
Control Valve Additions
Illustration 1.
The new control valves feature a building-block design that makes field installation of additional valves much easier (see Illustration 1). Attach a vacuum to the hydraulic tank to help control oil loss. Refer to your parts book for the hydraulic lines required.
The blade lift control valves, right and left, have threaded mounting holes in the body. All bolts from both sides are attached to this body. When adding control valves, longer bolts will be required. When removing control valves, shorter bolts will be required. Refer to your parts book for the correct bolts for your application.
Procedure To Add An Extra Control Valve
NOTE: In order to ensure proper alignment and to help the addition of a new control valve, see your Service Manual for the correct removal and installation procedure for the implement control valves.
1. With the control valve group on a clean work bench, set the control valve group in an upright position. This will assist in maintaining proper alignment of the control valve group during the disassembly and assembly procedure. Three bolts go through the end covers and bolt to the blade lift control valve. Remove one bolt. Install a 3/8 inch threaded rod in the bolt hole. Remove the other two bolts and install a 3/8 inch threaded rod in each hole. Remove the end cover and set aside.
NOTE: The 3/8 inch threaded rods will help maintain proper alignment between the control valves and the seal plates. Valves on the early machines had excessive clearance between the bolt holes and bolts. Later machines provide a much tighter fit.
NOTE: See your Caterpillar dealer for the correct control valve body for your application.
2. Clean all surfaces on the control valve groups and the new seal plates before starting any assembly procedures.
Illustration 2.
3. Install the new control valve group using new seal plates between the control valves, (see Illustration 2).
4. To ensure a proper seal between the control valves, carefully align the control valve seals and control valve bodies on the 3/8 inch threaded rods.
5. Install the end cover previously removed. Use the correct bolts found in your parts book for the number of control valves being used.
6. Remove one 3/8 inch threaded rod and replace it with the correct bolt. Tighten the bolt only enough to hold the group together. Check for proper alignment of the seal plates and the control valves. Repeat this step until all 3 bolts have been installed. Tighten the bolts to the final torque specification.
7. Install the control valve group on the machine.
Illustration 3.
8. Remove the rubber plug in the plate directly above the new control valve (see Illustration 3).
9. Install a new boot in the plate.
Illustration 4.
10. Install the rod assembly on the control valve lever with one bolt and lockwasher (see Illustration 4).
Control Levers
The control levers are location specific, with the capacity of fourteen, seven per side. The shaft the control levers ride on is designed to be shortened or lengthened to accommodate different numbers of levers by using different size retainers, shims, shaft extensions, and two lengths of the main shaft. The shims are as required to provide minimum end play allowing levers to return to normal position. Use the following Illustration and Charts 1, 2, 3 and 4 to determine the correct part number for your lever application. See your parts book for the correct knobs.
Illustration 5 (arrow depicts spacer. For machines with 3 inch spacer, use Chart 3. For machines with 2 inch spacer, use Chart 4.)
Configuration Change
NOTE: To help with the configuration change of a control valve and to ensure proper alignment of the control valve group, see your service manual for the correct removal and installation procedure for the control valves.
The valves are location specific (right and left as viewed from the operators seat), the following procedure describes how to change a control valve from right to left or from left to right, or to add or remove from one side.
Illustration 6.
1. With the control valve on a clean work bench remove the 101-2480 Cover.
2. Remove the 101-1971 Lever (this lever is threaded into the lever assembly).
3. Remove the lever assembly (the 101-1970 Lever Assembly is for the right side, 101-1982 Lever Assembly is for the left side).
4. Install the lever assembly using new seals and back-up rings. Use the correct lever assembly for the side the control valve will be used on.
NOTE: Lubricate the seal with a thin covering of the lubricant that is being sealed.
5. Install 101-1971 Lever and tighten to a torque of 25 ± 6 N·m (18.5 ± 4 lb ft).
6. Move the lever assembly (C) to ensure free movement.
7. Replace cover (B).
8. With the control valve group on a clean work bench, set the control valve group in an upright position. This will assist in maintaining proper alignment of the control valve group during the disassembly and assembly procedure. Three bolts go through the end cover and always bolt to the blade lift control valve. Remove one bolt. Install a 3/8 inch threaded rod in the bolt hole. Remove the other two bolts and install a 3/8 inch threaded rod in each hole. Remove the end cover and set aside.
NOTE: The 3/8 inch threaded rods will help maintain proper alignment between the control valves and the seal plates. Valves on the early machines had excessive clearance between the bolt holes and bolts. Later machines provide a much tighter fit.
NOTE: See your Caterpillar dealer for the correct control valve body for your application.
9. Clean all surfaces on the control valve groups and the new seal plates before starting any assembly procedures.
Illustration 7.
10. Install the new control valve group using new seal plates between the control valves, (see Illustration 7).
11. To ensure a proper seal between the control valves, carefully align the control valve seals and control valve bodies on the 3/8 inch threaded rods.
12. Install the end cover previously removed. Use the correct bolts found in your parts book for the new number of control valves being used.
13. Remove one 3/8 inch threaded rod and replace it with the correct bolt. Tighten the bolt only enough to hold the group together. Check for proper alignment of the seal plates and the control valves. Repeat this step until all 3 bolts have been installed. Tighten the bolts to the final torque specification.
14. Install the control valve group on the machine.
15. Add or remove the proper linkage for the valve. Add or remove the necessary control lever, shaft extensions, retainers, shims, and bolts as shown in Chart 3.
Flow Rates
The following charts list all the flow rates. The flow rates are given for both directions. The lower flow rate is for rod end oil and the larger flow rate is for head end oil. This function is to maintain equal speed of rod "in" and rod "out" travel. The detent shows Y for yes, N for none, and Y-HYD for hydraulic operated.
