Overview

Whether the issue is age, wear, or contamination, the MOOG D631-335C can often be restored. NC Servo Tech applies the same structured approach to every rebuild.

Independent Repair Facility

NC Servo Tech specializes in both valves and electronic controls, which lets us operate without the delays of OEM service centers.

50+ years of expertise in MOOG D631-335C Valve Repair

Frequently Asked Questions

Inspection and root-cause analysis are part of our standard process. We identify the issue before starting any repair work.

Not required, but removing excess oil or loose debris before packing helps keep things clean in transit.

We recommend sending pictures, especially if the model number is unclear or there is visible damage.

If a unit is beyond repair, we explain why and can discuss replacement or exchange options.

In most cases, repair costs less than replacement, especially for legacy or OEM-specific models. We evaluate every unit and let you know what makes sense.

How We Rebuild This Valve

We disassemble every valve, inspect it inside and out, and clean all moving parts. Components that fail inspection are swapped out before the valve is rebuilt and tested.

  • Cleaning: Units go through a mineral bath, with ultrasonic cleaning used for delicate internals.
  • Final Performance Verification: After reassembly, each valve is bench-tested against published performance specifications.
  • Seal and Gasket Replacement: Worn seals and gaskets are replaced with new components during every rebuild.
  • Leak and Pressure Testing: The reassembled unit is leak-tested and pressure-tested to verify it meets published specs.

Testing and Bench Verification

NC Servo Tech operates over a dozen dedicated flow test stands, including setups for proportional and servo valves. Every valve goes through performance and leak testing using industry-standard fluids including MIL-5606 and Skydrol. Our performance testing verifies consistent performance.

Repair, Rebuild and Exchange Options

Beyond standard sales, we offer specialized repairs for your MOOG D631-335C unit. Our teardown process includes leak testing and bench testing, using only replacement replacement components.

Lead Times and Support

As a specialist for MOOG D631-335C services, NC Servo Tech targets quick resolution with typical lead times of 1 to 2 weeks. Benefit from our dedicated support team to keep your systems running smoothly.

Maintenance Tips

  • Schedule preventive maintenance intervals based on duty cycle, not just calendar time.
  • Store spare MOOG D631-335C valves in a clean, dry environment to prevent corrosion and contamination.
  • Use only manufacturer-recommended hydraulic fluids to protect internal valve surfaces.

Let Us Repair Your MOOG D631-335C

Request pricing, availability, and turnaround for your MOOG D631-335C. NC Servo Tech provides hands-on repair with a 1-year warranty. Contact us to start your repair.

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NC Servo Tech is an independent third-party repair facility. We are not affiliated with, endorsed by, sponsored by, or authorized by MOOG or any original equipment manufacturer (OEM), nor do we claim to be a MOOG service center. All brand names, trademarks, model numbers, and part numbers referenced on this page are the property of their respective owners and are used solely for identification and compatibility purposes.