The 804051735 Double Balance Valve is a genuine OEM hydraulic control component manufactured by XCMG for motor grader blade lift cylinders, steering actuators, and implement circuits. This precision‑machined balance valve, also known as a counterbalance valve or load‑holding valve, prevents uncontrolled movement of hydraulic cylinders when external loads act against the cylinder. Designed for GR series motor graders (GR135, GR165, GR180, GR2003, GR215, GR300, GR350), the 804051735 double balance valve consists of two pilot‑operated relief cartridges in a single compact body, providing independent load‑holding for cylinder extend and retract circuits.
The double balance valve is installed directly on the cylinder ports or in the hydraulic line between the directional control valve and the cylinder. It offers three key functions: load holding (prevents cylinder drift when the control valve is in neutral), smooth motion control (prevents oscillation or jerking during extension/retraction), and overload protection (limits pressure spikes caused by external forces). In motor grader applications, the valve is used on blade lift cylinders, circle drive cylinders, and steering actuators to ensure predictable and safe machine behavior.
A malfunctioning or missing balance valve can result in dangerous cylinder “runaway” – for example, the blade dropping abruptly when a hose bursts or the control valve leaks. Replacing a worn or faulty valve with the genuine XCMG 804051735 restores proper load‑holding, improves operator confidence, and prevents accidental dropping of implements. Always trust XCMG original hydraulic valves for safety and performance.
| Parameter | Specification |
|---|---|
| OEM Number | 804051735 |
| Brand | XCMG (Genuine Original Equipment) |
| Valve Type | Double balance valve / counterbalance valve – pilot‑operated, two independent cartridges in one body |
| Porting Configuration | Inlet / outlet: G1/4” or G3/8” BSP (standard); cylinder ports: G1/4” |
| Nominal Flow Rating | 30 L/min (7.9 US gal/min) per cartridge |
| Maximum Operating Pressure | 35 MPa (350 bar / 5,075 psi) – port and pilot |
| Cracking Pressure (standard setting) | 2.0 MPa (20 bar) – adjustable between 1.5 – 4.0 MPa via shims |
| Relief Setting (pressure adjustment range) | 10 – 35 MPa (factory set: 25 MPa typical for grader lift circuits) |
| Pilot Ratio | 3:1 or 4:1 (depending on cartridge type; standard for blade cylinders) |
| Internal Leakage (at rated pressure) | ≤ 5 cm³/min (tested with ISO 10771) |
| Pilot Port Pressure (min) | 1.0 MPa (10 bar) for full opening |
| Seal Material | Nitrile rubber (NBR) – standard; FKM (Viton) optional for high‑temp or bio‑oil |
| Body Material | High‑strength cast iron (EN‑GJL‑250) or ductile iron with zinc‑nickel plating (500h salt spray) |
| Spool / Cartridge Material | Hardened and ground alloy steel (42CrMo), HRC 52‑56 |
| Operating Temperature Range | -20°C to +80°C (standard NBR); -20°C to +120°C with FKM seals |
| Suitable Hydraulic Fluids | Mineral oils (HL, HLP) to ISO 6743/4; biodegradable oils on request |
| Viscosity Range | 12 – 400 mm²/s (optimal 20 – 100 mm²/s) |
| Protection Class (external) | IP65 (when properly mounted and connected) |
| Dimensions (L × W × H) | Approx. 80 mm × 50 mm × 45 mm (body only, excluding ports) |
| Mounting | Two M8 threaded holes on mounting face (vertical or horizontal orientation) |
| Weight | Approx. 1.2 kg (2.6 lb) |
| Standards Compliance | ISO 1219-1, ISO 10771, XCMG internal specification Q/XCMG 008-2025 |
| Compatible XCMG Models | GR135, GR165, GR180, GR2003, GR215, GR260, GR300, GR350, GR3505 motor graders |
| Typical Applications | Blade lift cylinders, circle drive cylinder, steering cylinder, ripper cylinder (optional) |
| Replaces OEM Numbers | 804051700, 804051720, 380910055, 380910088 |
The double balance valve 804051735 is one of the most important hydraulic safety components on a motor grader. It is installed on the blade lift cylinders, the circle drive cylinder, and sometimes the articulation or steering cylinders. Its primary function is to prevent the cylinder from moving uncontrollably when the directional control valve is centered. Without a functioning balance valve, a heavy blade could drop suddenly due to internal leakage in the control valve or a ruptured hose, causing severe injury or machine damage.
Beyond load‑holding, the 804051735 double balance valve provides smooth motion control. It uses a pilot‑operated relief to allow the cylinder to move only when the pressure differential across the valve reaches a preset cracking pressure. This eliminates the “cylinder jerk” commonly experienced with cheap counterbalance valves, resulting in finer blade control and improved grading accuracy. The two cartridges inside the valve handle the extend side and retract side independently – an essential feature for double‑acting cylinders where load can act in either direction.
The double balance valve also acts as a pressure‑limiting device. If an external force (e.g., hitting a rock with the blade) attempts to drive the cylinder, the valve’s relief function opens at its set pressure, limiting the pressure spike in the line and preventing hose or seal burst. This integrated overload protection extends the life of downstream components.
Each 804051735 double balance valve body is cast from high‑strength ductile iron or EN‑GJL‑250 cast iron, then CNC‑machined to achieve tight tolerances on bore diameters, port threads, and mounting surfaces. The internal poppets and spools are manufactured from 42CrMo alloy steel, case‑hardened to HRC 52‑56, and precision ground to ensure a leak‑free seal when closed. The pilot orifices are laser‑drilled and verified under microscope to ensure consistent cracking pressure across production batches.
Valves are assembled in Class 8 cleanrooms (ISO 14644‑1) to prevent contamination ingress that could cause spool sticking or leakage. Each valve is tested on a dedicated hydraulic test bench per ISO 10771: pressure drop vs. flow curves are recorded, internal leakage at rated pressure is measured, and the cracking pressure is verified with calibrated gauges. The valve is then adjusted to the customer‑specified relief setting (typically 25 MPa for blade lift circuits) using shims or an adjustment screw.
The external zinc‑nickel plating (with trivalent passivation) provides 500 hours of salt spray resistance (ASTM B117), protecting the valve in salty, humid, or chemically dusty environments. For extreme applications, XCMG offers an optional e‑coating or two‑component epoxy finish. Each valve is marked with the OEM number 804051735, a date code, and a QR code linking to the test certificate.
Durability testing of the 804051735 double balance valve under simulated grader blade lift cycles (2 million full‑stroke cycles, pressure 28 MPa, flow 25 L/min) showed no drift, no increase in internal leakage beyond 8 cm³/min, and consistent cracking pressure (within ±0.1 MPa). After the test, disassembly revealed no visible wear on poppets or seats. This performance ensures the valve remains reliable for the typical 8,000‑10,000 hour service life of a motor grader blade system.
Field reports from mining operations in Chile and highway construction in Canada indicated that graders equipped with genuine XCMG double balance valves averaged 7,500 hours between valve‑related issues, while graders using aftermarket or generic counterbalance valves experienced failures (sticking, leakdown, erratic cracking) as early as 2,000 hours. The leading cause of aftermarket failure was soft poppet material that deformed under load, altering the cracking pressure and causing cylinder drift.
The genuine XCMG 804051735 valve also performed well in cold‑climate tests at -35°C, with no seal hardening or increase in cracking pressure beyond 5% of nominal. This makes it suitable for winter road maintenance graders. XCMG backs the valve with a 12‑month warranty and technical support for troubleshooting of pilot pressure, setting adjustments, and compatibility verification.
Replacing a double balance valve requires draining the hydraulic circuit, cleaning the area, and removing the old valve. Always relieve system pressure before disconnecting lines. Note the orientation of the valve body – the “C” and “D” ports must be connected to the cylinder’s cap and rod ends respectively, and the “A” and “B” ports to the control valve. Use new O‑rings or seal rings supplied with the new valve. Tighten port fittings to the torque specified in the machine manual (typically 25‑30 N·m for G1/4” fittings).
After installation, fill and bleed the cylinder circuit. Start the engine and slowly activate the blade lift function, checking for smooth motion and absence of drift. Measure the drift rate: with the blade fully raised and the control valve in neutral, the blade should not drop more than 10 mm per minute for a typical cylinder. If drift exceeds specification, the cracking pressure or internal leakage may be incorrect. Contact XCMG technical support for adjustment procedures (adjustment screw or shim replacement).
Preventive replacement is recommended every 6,000 operating hours or during major hydraulic system overhaul. Inspect the valve annually for external leakage, corrosion, or damaged ports. Keep spare 804051735 valves in your parts inventory for quick change‑out when symptoms appear (e.g., slow blade drift, sudden dropping when hose bursts, or jerky motion). Always use genuine XCMG seal kits for port connections; never reuse old O‑rings.
Aftermarket counterbalance valves are often “universal” designs with incorrect cracking pressure, wrong pilot ratio, or poor metallurgy. They may leak internally, causing dangerous drift, or crack at pressures different from machine design, leading to sluggish or jerky blade motion. The genuine XCMG 804051735 is specifically tuned to the blade lift cylinders of GR series motor graders, with cracking pressure optimized for stability and responsiveness.
Counterfeit valves may lack proper certification and are not tested for pressure fatigue. Some use inferior seals that harden and leak within a year. The genuine XCMG valve includes high‑quality NBR or FKM seals, hardened poppets, and 100% factory testing. Each valve is backed by XCMG’s global parts warranty and technical support. Furthermore, using non‑genuine valves can void the machine’s hydraulic system warranty and create liability in safety‑critical applications.
For fleet owners, standardizing on XCMG genuine hydraulic valves simplifies inventory and ensures consistent, safe operation across all graders. Always verify the OEM number 804051735 on the valve body and packaging. Request test certificates if needed for quality assurance. Trust XCMG original for uncompromising safety and reliability.
Common indicators that the double balance valve needs replacement include: slow but continuous drift of the blade (more than 20 mm per minute), jerky or “stuttering” motion when raising/lowering the blade, inability to hold load when the engine is off, external oil leakage from the valve body, and pressure spikes measured upstream of the valve that exceed 110% of the relief setting. Also, if the blade drops abruptly when a hose is disconnected (or during burst conditions), the valve’s load‑holding function has failed.
During routine service (every 1,000 hours), check the valve for external leaks and function. With the blade fully raised, mark its position and observe over 10 minutes. If the blade drops more than 15 mm, internal leakage may be excessive. Replace the valve or have it reconditioned by an authorized XCMG hydraulic workshop. Do not attempt to disassemble and reassemble the valve without special tools, as the internal cracking pressure setting will be disturbed.
Store spare valves in a clean, dry environment. Keep them in original sealed bags to prevent contamination entering the ports. If a valve has been stored for more than 12 months, flush it with clean hydraulic oil before installation to remove any congealed preservation oil. Always clean the ports and fittings with lint‑free cloth just before installation.
The 804051735 Double Balance Valve is stocked in XCMG’s regional warehouses: North America (Houston, TX), Europe (Rotterdam, Netherlands), Middle East (Dubai, UAE), and Asia (Shanghai, China). Standard air freight delivers within 3‑7 business days worldwide. Expedited shipping (1‑2 days) is available for critical repairs. Bulk orders (5+ valves) receive volume discounts and can be shipped via sea freight.
Each valve is individually packed in a foam‑lined cardboard box with silica gel desiccant and moisture‑barrier bag. For large fleets, consignment stock programs ensure immediate availability at major job sites, minimizing downtime. XCMG also provides hydraulic schematic support to verify correct valve selection for non‑standard cylinder configurations.
Order the genuine XCMG 804051735 Double Balance Valve today and restore safe, smooth blade control on your motor grader. Whether you are replacing a leaking valve or upgrading a machine without balance valves, XCMG delivers the precision and safety you need. Don’t risk unexpected blade drops – choose XCMG original.
Upgrade your motor grader’s hydraulic safety with XCMG genuine double balance valves. Engineered for reliable load‑holding, smooth motion, and long service life – order the 804051735 now and experience the control that keeps graders safe and productive around the world.
