About This Unit

We’ve serviced hundreds of MOOG D631-334FA units over the years. Each one goes through the same controlled teardown, parts replacement, and testing process.

About Our Shop

As a specialized repair facility, we have dedicated test equipment that general-purpose shops don’t. That means your MOOG D631-334FA gets serviced by people who work on these units regularly.

50+ years of expertise in MOOG D631-334FA Valve Repair

Frequently Asked Questions

We regularly work on units with missing labels. Send us a few images and any visible part numbers, and we can usually match it.

Rush and priority service options exist. Availability depends on current workload, so contact us early.

Part of our intake includes troubleshooting to determine the failure point. We report findings before proceeding.

Warranty coverage of a 12-month warranty on parts and labor is included with every repair we complete.

No cleaning required. Our repair process includes disassembly and cleaning of all components.

Repair Process

Each valve goes through teardown to expose wear and buildup. After mineral bath cleaning, we replace damaged parts and reassemble the unit to spec.

  • Complete Disassembly: The unit is disassembled and all parts are laid out for individual inspection.
  • In-House Parts Sourcing: Many repairs use components sourced from our inventory of 17,000+ units.
  • Cleaning: Units go through a mineral bath, with ultrasonic cleaning used for delicate internals.
  • Seal and Gasket Replacement: Worn seals and gaskets are replaced with new components during every rebuild.

Testing and Bench Verification

Each MOOG D631-334FA is tested on a dedicated flow bench before it ships. We check pressure, flow, leakage, and response characteristics against published specifications. Our operational testing verifies proper functionality.

Common Applications

Our expert repair services for the MOOG D631-334FA are trusted across various sectors including Oil & Gas, Paper & Pulp, and Plastics & Injection Molding. We understand the unique demands of valves in these environments.

Repair, Rebuild and Exchange Options

Beyond standard refurbishment, we offer specialized repairs for your MOOG D631-334FA unit. Our disassembly process includes mineral bath cleaning and internal inspection, using only new replacement components.

Maintenance Tips

  • Schedule preventive maintenance intervals based on duty cycle, not just calendar time.
  • Replace inline filters according to maintenance schedules to maintain proper flow rates.
  • Keep hydraulic fluid clean and at proper levels for consistent valve operation.

Ready to Restore Your MOOG D631-334FA?

Request pricing, availability, and turnaround for your MOOG D631-334FA. NC Servo provides experienced repair with a 1-year warranty. Contact us to start your repair.

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NC Servo 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.