Installation Method for the Directional Control Valve of Minsk Tractor (Belarus)

I. Pre-installation Preparation (Universal)

1. Safety Pressure Relief and Power-off

• Stop the engine and turn off the flame, release the pressure of the hydraulic system (loosen the oil return port plug / open the pressure relief valve), and disconnect the negative pole of the battery to prevent misoperation.

• Wear oil-resistant gloves and goggles to avoid high-pressure oil splashing; it is strictly prohibited to disassemble pipelines without relieving system pressure.

2. Compatibility and Component Inspection

• Verify the valve body model (such as 060 series steering control valve) and oil port identification (P for oil inlet, T for oil return, A/B for working oil ports) to ensure they match the tractor's hydraulic system.

• Check that the valve body has no cracks, the valve core moves flexibly, and the seals are intact; new valves must have a certificate of conformity, and worn sealing rings, valve cores/valve sleeves of used valves must be replaced.

3. Tools and Consumables

• Tools: 10–19mm socket set, torque wrench, rubber hammer, hydraulic oil pipe wrench, seal ring installation tool, level ruler, cleaning agent / compressed air.

• Consumables: Original factory seal rings, PTFE thread sealant, hydraulic oil (meeting MTZ specifications), clean lint-free cloth.

II. Mechanical Positioning and Fastening (Universal + Model-specific Key Points)

1. Positioning Datum

• Determine the installation position according to the original factory manual (mostly beside the driver's seat / near the rear axle). Keep the directional control valve axis horizontal to facilitate operation and maintenance.

• MTZ-80/82: Install beside the front axle steering mechanism, align with the 4 fixing bolt holes, and ensure the valve core is coaxial with the steering connecting rod.

• MTZ-900 series: Install on the bracket beside the hydraulic pump, reserve operation space and pipeline routing allowance.

2. Pre-tightening and Final Tightening

• Manually screw in the original factory bolts to ensure full thread engagement without misalignment; use a torque wrench to tighten them step by step in a cross-symmetrical manner (diagonal grouping).

• Torque parameters (general reference, subject to the model manual):

3. Sealing and Protection

• When installing the flange, tighten the bolts evenly to avoid poor sealing caused by over-tightening; unused oil ports must be blocked with original factory plugs.

• Install a protective cover after installation to prevent dust and debris from entering, and keep away from high-temperature and moving parts.

III. Pipeline Connection Specifications (Universal + Model-specific Key Points)

1. Oil Circuit Connection

• Connect according to the schematic diagram: Port P is connected to the hydraulic pump oil outlet, Port T to the oil return tank, and Ports A/B to the corresponding chambers of the steering cylinder. Reverse connection is strictly prohibited.

• Note for MTZ models: Install a filter at the oil inlet, and ensure the oil return port is higher than the oil level of the tank to avoid cavitation.

2. Joint and Fixing

• Clean the oil pipe joints, wrap PTFE thread sealant clockwise, and tighten according to the specified torque; fix the pipelines with original factory clips, keep a distance of ≥ 15cm from high-temperature components, and stay away from moving parts.

• Avoid twisting or bending the hoses, and ensure the bending radius is ≥ 10 times the pipe diameter to prevent oil flow obstruction.

3. Exhaust

• After connection, pull the joystick repeatedly, open the exhaust valve (if available) to discharge air; start the engine to run at idle speed, turn the steering repeatedly until no air bubbles overflow, and replenish hydraulic oil to the oil level line.

IV. Commissioning and Functional Testing (Universal)

1. No-load Test

• Start the engine; the joystick should operate flexibly without jamming or abnormal noise; steering should be light without deviation, and the valve core should return to the original position normally.

• Check that all interfaces have no leakage, the valve body temperature is ≤ 60℃, and there is no abnormal vibration.

2. Load Test

• When the tractor is driving straight, the steering should have no lag, and the left and right steering angles should be consistent (in line with the original factory parameters).

• The hydraulic system pressure should be stable (usually 16–18 MPa for MTZ models) without pressure drop or fluctuation.

3. Troubleshooting

• Heavy steering: Check the pressure, valve core jamming, and oil circuit blockage. Leakage: Replace the seal ring and re-tighten the joint.

• Unstable steering: Check the valve core return spring and oil cleanliness; clean the valve body if necessary.

V. Safety Specifications (Universal)

1. Implement full-process pressure relief operation; it is strictly prohibited to disassemble pipelines/valve bodies without pressure relief to prevent injury from high-pressure oil.

2. It is strictly prohibited to strike the valve body with metal tools to avoid valve core deformation and seal failure.

3. Recheck the correctness of oil ports after pipeline connection, and exhaust air before starting to prevent cavitation damage to hydraulic components.

Cautions for Installation of the Directional Control Valve of Minsk Tractor (Belarus) (MTZ Series)

I. Core Hydraulic Safety Cautions

1. Full-process Pressure Relief Operation Specifications

• Stop the engine and turn off the flame before installation. Fully release the residual pressure in the hydraulic pipelines by loosening the oil return port plug or opening the system pressure relief valve. It is strictly prohibited to disassemble or install valve bodies and pipelines under pressure to prevent personal injury caused by high-pressure oil splashing.

• Disconnect the negative cable of the battery to prevent accidental movement of the valve core caused by touching the joystick during installation, which may lead to mechanical collision accidents.

• Wear oil-resistant gloves and goggles during operation to avoid hydraulic oil contacting the skin. If hydraulic oil splashes into the eyes, rinse immediately with plenty of clean water and seek medical attention.

I. Authoritative Technical Bases (Compliance and Specification Sources)