Rexroth A8VO140 Variable Displacement Swashplate Hydraulic Pump

Unlike a standard single-flow pump, the A8VO series uses a swashplate design with two independent rotating groups inside one housing.

The Twin-Flow Advantage

Imagine needing to drive a dual-track vehicle. With the A8VO140, one pump half supplies the left track motor while the other half supplies the right. This gives you true, independent control without a complex shunt valve. The “140” refers to the geometric displacement per rotating group—140 cc/rev—meaning the total pump displacement can reach 280 cc/rev when both sides are summed.

Swashplate Mechanics in Action

The variable swashplate changes the piston stroke length. At zero angle, flow stops. At maximum angle, you get full 140cc per side. What makes the Rexroth design superior is its fast response control pistons—they adjust the plate in milliseconds, minimizing lag when you transition from fine positioning to high-speed travel.

Performance Tuning: Matching the Pump to the Load

You don’t buy an A8VO140 just to move oil. You buy it to manage power.

Pressure and Flow Limiters

A common mistake: running the pump at its 4500 psi continuous rating without a proper power limiter. The A8VO140 includes integrated high-pressure cutoff and torque control. For example, in a concrete mixer drum, the pump automatically reduces displacement when the drum binds against thick concrete—preventing stall or hose rupture.

Control Options: From Manual to Electro-Hydraulic

Rexroth offers multiple control variants for the A8VO140. Choosing the wrong one leads to poor response or overheating.

Common Control Types

DA Control (Speed-related) : Ideal for hydrostatic fans or winches. Output flow follows input shaft RPM.

EP Control (Electro-proportional) : For precision robotics or pavers. A 4-20 mA signal gives you stepless flow control.

HD/HD2 Control (Hydraulic pilot) : The workhorse for mobile excavators. Simple, durable, and fails to neutral.

Pro tip: If you are retrofitting an older machine, the HD control is most forgiving of dirty pilot oil. For new automation, EP control with a Bosch RE31 controller unlocks diagnostic feedback.

Maintenance Schedule: Don’t Trust the Hour Meter

Most operators follow a 2000-hour oil change. For the A8VO140, we recommend condition-based maintenance.

Every 500 hours: Sample oil. Look for ISO 4406 code >18/16/13. That is your warning.

Every 1000 hours: Replace the case drain filter (often overlooked). A blocked case drain blows the shaft seal.

4000 hours: Inspect the two rotating groups for brass plating (micro-welding). If present, your viscosity index is too low—switch to a 46-grade synthetic.

For more information on the A8VO140 hydraulic pump, please visit https://www.baolilaihydraulic.com/product/.

Specifications

Selection Table

Q1: The pump is noisy after cold start. Normal?

A1: For the first 30 seconds, yes. The swashplate needs warm oil to actuate fully. But if noise persists beyond 2 minutes at idle, check the suction strainer. The A8VO140 requires at least 0.8 bar absolute inlet pressure. Many failures come from undersized suction hoses.

Q2: Can I parallel two A8VO140 pumps off one prime mover?

A2:Absolutely. Use a splitter gearbox. However, stagger the swashplate control signals by 50ms to avoid pressure ripple resonance in the common suction line.

Q3:How to purchase an A8VO140 hydraulic pump?

A3:You can visit https://www.baolilaihydraulic.com/contact/ to contact us and purchase our products through various methods.

Q4:What is the price and delivery time of the A8VO140 hydraulic pump?

A4:The specific price and delivery time will be provided based on the specific model you provide.