Product Overview

The QUY35T needs a motor that holds its displacement under load and a balance valve that stops the load creeping the moment the control goes back to neutral. We supply the motor and its KDC30MR balance valve together, because that is how the drive circuit is built and how most workshops replace it. If the machine has lost drive pressure, is slow to build pressure from cold, or lets a held load drift, this is the assembly to look at first.

Anyone working through a hydraulic crane parts list for this machine arrives here by number rather than by description, and that is the right way round: the reference on the old unit decides what fits, while a photograph only tells you it is a red hydraulic motor of roughly the right size.

We are crane spare parts suppliers for the FUWA range rather than a counter tied to a single brand, so we can say plainly whether a number is current, superseded or simply wrong for the machine — usually before anything is ordered.

The assembly is one of those construction machinery spare parts where the casting, the port pattern and the valve setting all have to line up at once. A motor that bolts on but was built for a different circuit will run hot; a valve set for another motor will either hold too hard or let the load slip. Getting both halves right for the QUY35T is what makes the repair last.

Specifications

Motor & Balance Valve Assembly

• The motor. Inside an axial piston motor, displacement is varied by the swashplate angle, so the unit can build torque at low speed instead of stalling when the load comes on. That behaviour is exactly what the QUY35T's drive relies on.
• The balance valve. A counterbalance valve meters oil out of the motor's return side, so a suspended load descends only as fast as oil is allowed to leave. When it wears, the first sign is usually creep — the load drifts with the control in neutral, or drops a little when the operator lets go.
• Why both halves go together. Valve setting and motor displacement are chosen as a pair. Fitting a new motor onto a worn valve is the most common reason a repair comes back a month later, and a valve from another motor reference will not hold correctly even when the threads match.
• Cast and machined. The body is a casting, machined afterwards on the port and mounting faces so the flanges sit flat against the manifold. The assembly carries a lifting eye, which is how it should be swung into place rather than manhandled on the bench.
• Painted and labelled. The housing is painted before dispatch and every unit carries an identification label with its references on it. Photograph that label before the old unit leaves the bench — it is what the next order is built from.
• Specific to the machine. As crane spare parts go, this one is not interchangeable by flange size: the valve is part of the fitment, and the assembly is specified for the QUY35T rather than for the whole range.

Matching the Assembly to Your Machine

1. Read the label on the old motor before it comes off: the full reference string, not just the M3X prefix. It is the only reliable way to order crane spare parts for this circuit, because two motors that look identical from outside can carry different valve settings.
2. Note the balance valve number separately. The valve has its own reference, it often fails before the motor does, and it is the number most often left off an enquiry.
3. Record the machine model and serial from the plate on the crane, so the order is checked against the build rather than against the model name alone.
4. Put the new unit beside the old one on the bench before fitting: port positions, flange thickness, shaft spline and overall length should all match. A difference is far easier to resolve before the machine is in pieces.
5. Confirm which machine the unit is going onto. Mobile crane parts and other crane models use their own motor and valve references; across construction machinery spare parts, the flange pattern alone will not tell you which one you need.
6. Write every reference down in one go — motor, valve, machine and any crane electrical components ordered at the same time. Controllers, monitors and limiters each carry their own number, and a single list keeps a mixed order straight.

Motor Range & Related Parts

• The reference on this assembly. M3X530ACN-XV022A, paired with balance valve KDC30MR-A3.1/235-752A — the number to quote when you replace the unit as a set.
• Other M3X530 motors. M3X530APN-467-RV038A, M3X530ACM-485-XV034A, M3X530BPN-533/370-XV143A, M3X530APM-485-RV037A, M3X530BPN-485-RV030B, M3X530APM-485-RV024A and M3X530APM-485-RV025A cover the rest of the family on FUWA cranes.
• M3X280 and M5X180 motors. M3X280BPN-252-XV004A and M3X280BPN-252-XV007A sit in the smaller M3X group; M5X180CHB-13A-76A-169-RG23C34B6-T and M5X180A0BT14A-45A-RG23C34B5-L are the M5X references most often asked for alongside them.
• M3B series. M3B530BC-485/280-XV078A, M3B280BP-252/166-XV037B, M3B280BP-252/166-XV038B, M3B800BP-800/369-XV092A and M3B800BP-533/242-RV146B cover the larger motor sizes.
• Other motor types. Alongside these piston motors we handle variable displacement and axial plunger motors of the Bosch Rexroth and Kawasaki types used on FUWA and other cranes.
• Pump side. The Kawasaki K5V160DTH piston pump is the companion reference on the same circuit and sits in the same hydraulic range.
• Electrical side. Controllers, monitors, limiters, sensors and cab switches come from the same FUWA parts stream, so crane electrical components can be added to a motor order rather than shipped separately.
• Load moment system. Load cells, angle sensors and the crane load indicator itself are ordered separately from the hydraulic parts; after a long shutdown they are usually bought in the same batch as the drive repair.
• If the machine is not a QUY35T. Mobile crane parts and other models use their own motor and valve combinations — send the model with the number and we will check which line it belongs to.
• If the number is not listed. As crane parts suppliers we keep the wider M3X, M5X and M3B families on file, so send whatever is stamped or printed on the old unit and we will confirm it against the range.

Fitting & Commissioning

1. Cleanliness decides how long the repair lasts. Of all the construction machinery spare parts on a crane, hydraulic motors are the least forgiving of dirt: drain or flush the circuit, check the oil for metal, and keep the new unit sealed until the bench and the fittings around it are clean.
2. Label every hose before it comes off. Hydraulic crane parts rarely fail twice for the same reason; they fail the second time because a line went back on the wrong port, and the symptoms then look identical to the original fault.
3. Mount the assembly on clean, dry flange faces and tighten the port bolts in a cross pattern rather than working around the circle.
4. Fill the motor case with clean hydraulic oil before the first start, and leave the fill port open long enough to let air out of the housing.
5. Start at low engine speed with no load, work the control through a few full movements, and stop immediately if the motor is noisy or the case runs hot.
6. Load up gradually over the first working period. A unit that creeps under load at this stage is telling you the valve setting or the circuit pressure is wrong, not that the motor is worn.
7. After the first shift, check for leaks, re-torque the port bolts and watch the crane load indicator and limiter through a full cycle. If either reads differently from before the repair, stop and investigate before the crane goes back to work.

Ordering & Delivery

About FUWA

FUWA started in 1904, which makes it the longest-established construction equipment manufacturer in China, and crawler cranes have been central to its range for decades. The QUY line runs from compact lifting units up to heavy-lift machines, and the QUY35T sits towards the smaller end — often the first crane onto a bridge or plant site and the last to leave. The company has kept developing new models and refining its production and management as the range has grown, and that long production history is why so many crawler crane parts are still available for older machines.

We have been buying and supplying original FUWA crawler crane and spare parts from China for close to ten years. Our market now covers more than twenty countries, with after-sales service stations in many of them. As crane parts suppliers for the QUY range we can also send our crane engineers to site when a fault needs eyes on the machine rather than a part in a box.

Every QUY crane works to a rated load chart, and the crane load indicator on the machine is what keeps the operator inside that chart. The hydraulic side exists to deliver the motion the chart assumes, at the speed the operator asks for — nothing more, and certainly nothing less.

Technical Support & Model Matching

Not sure which part matches your machine? Send us the model, serial number and the original part number — or a photo and key dimensions — and our engineers will confirm the correct item and check availability before you commit. They have spent more than ten years in construction machinery and can talk you through fault-finding, installation and commissioning by phone, email or video. We also trace parts for discontinued and legacy models. Support runs 24/7 from Shenyang, China, where we have been supplying buyers since 2017.

FAQ