A4VG Series Hydraulic Pump Control Valve EZ EP HD D DA Regulator Excavator Replacement

A4VG Series Hydraulic Pump Control Valve – EZ, EP, HD, D, DA Regulator Assemblies

These are the control valve / regulator assemblies used on A4VG series variable displacement axial piston pumps. The control type determines how pump displacement is regulated – electrically, hydraulically, or by pressure – and it is encoded by a letter group in the pump model code. Fitting the wrong control type means the pump physically bolts on but does not regulate as the machine expects, so the model code has to be checked before ordering.

Available Control Types

Technical Specifications

Key Features

• Control type matched, not guessed. Regulators are supplied against the exact control letter group in your pump model code, so displacement regulation behaves as the machine expects.
• Bench checked. Each regulator is checked for spool movement, response to the control signal and internal leakage before packing.
• Five control variants in one supply chain. EZ, EP, HD, D and DA types can be consolidated in one shipment, which simplifies stocking for repair shops.
• Seal kit option. We can quote the matching seal kit and adjusting screws with the regulator so the repair is completed in one pass.
• Factory direct supply. Sourced and inspected in Guangdong, with stock available for urgent breakdown orders.

Fitment Notes

Please send the complete pump model code stamped on the pump nameplate (the letter group after the displacement figure identifies the control type) together with photos of the regulator and its connector or pilot port. Excavators using the same pump frame can carry different control types, so we confirm against your nameplate within 24 hours before shipping.

FAQ by Market

Q1: North America & Europe – how do I confirm the control type before I pay?
Send a photo of the pump nameplate showing the full model code, plus photos of the regulator and its connector or pilot port. We confirm the control letter group and wiring or port arrangement within 24 hours, and can supply dimension drawings for approval.

Q2: European Union – what documents come with the shipment?
Each order ships with commercial invoice, packing list and a technical datasheet for customs clearance. Tell us if your market requires additional conformity documents and we will confirm what we can provide for your order.

Q3: Middle East & Africa – what causes regulator failure in hot, dusty conditions?
Most regulator faults come from contaminated oil blocking the spool. We recommend flushing the system and renewing the return filter at the same time, and can quote the seal kit with the regulator. Ask us for the oil viscosity and service interval for your ambient temperature.

Q4: Southeast & South Asia – what is the minimum order and how do we talk price?
Minimum order is 1 unit and the price is negotiable – it depends on the control type, quantity, shipping mode and whether you consolidate several regulators in one shipment. Send your list and we will quote accordingly.

Q5: Russia & CIS – can the regulator work in low temperature?
Yes, with the correct hydraulic oil grade. Tell us your winter ambient temperature and we will recommend the oil grade and warm-up procedure, and can quote low-temperature seals on request.

Q6: South America & Australia – lead time and after-sales?
Delivery is normally 15–30 days after order confirmation, and warranty terms and claim procedure are agreed with your sales contact before shipment, including how to submit photos or video of the regulator in operation for assessment.

Request a Quotation

Send us your pump model code, the control type you need, the quantity and your destination port. Our team will reply with pricing, warranty terms, stock status and shipping options – and if the regulator is not what you need, we will quote an alternative from our range.