Key Details

We’ve serviced hundreds of MOOG D664-820A units over the years. Each one goes through the same controlled teardown, parts replacement, and testing process.

Teardown and Rebuild Steps

Each MOOG D664-820A undergoes reconditioning — disassembly, parts replacement, reassembly, and bench testing before shipment.

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.

Yes, rush service is available for an additional fee. Let us know your deadline when you submit your request.

We give you a straight assessment after inspection. If repair doesn’t make sense, we’ll let you know and discuss alternatives.

Turnaround time varies by model and condition. Contact us for a timeline specific to your unit.

Warranty coverage of our standard 1-year parts and labor warranty is included with every repair we complete.

About Our Shop

Unlike OEM shops, we use our own inventory to handle most rebuilds. That cuts down on lead time and gets your unit back faster.

Factory-level test stands dedicated to MOOG D664-820A performance verification

Rebuild Steps

Every MOOG D664-820A gets a controlled teardown on our bench. We document condition, replace what’s needed, and reassemble to proper operating condition.

  • 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.
  • Leak and Pressure Testing: The reassembled unit is leak-tested and pressure-tested to verify it meets published specs.
  • In-House Parts Sourcing: Many repairs use components sourced from our inventory of 17,000+ units.

Diagnostic Testing

With our 13-stand test facility and a Hagenbush proportional valve system, we verify flow curves, hysteresis, frequency response, and more. Performance reports and graphs are available for purchase on request. Our functional testing verifies consistent performance.

MOOG D664-820A Specifications

Every MOOG D664-820A we service is tested under real-world conditions. Our diagnostics verify performance against published specifications. Performance data and Cycle life data are available for purchase upon request.

Turnaround and Shipping

As a specialist for MOOG D664-820A services, NC Servo targets quick resolution with typical lead times of 2 to 3 weeks. Benefit from our direct access to our technicians to keep your systems running smoothly.

Parts and Inventory

With over 17,000 valves in stock, we can often provide faster turnaround by sourcing parts in-house rather than waiting on OEM lead times.

Maintenance Tips

  • Check system pressure regularly to verify it stays within the MOOG D664-820A rated operating range.
  • Conduct thorough visual inspections for wear or leaks during routine maintenance.
  • Document all maintenance activities to track performance trends over time.

Let Us Repair Your MOOG D664-820A

Request pricing, availability, and turnaround for your MOOG D664-820A. 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.