Teardown and Rebuild Steps

Our repair process for the MOOG 77-128 begins with teardown and mineral bath and ultrasonic cleaning to assess all components.

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.

17,000+ valves in stock including MOOG 77-128 exchange units

Frequently Asked Questions

All repairs come with a 12-month warranty on parts and labor. Contact us for specifics on your unit.

You’ll hear from us either way. If it’s not repairable, we’ll return the unit and provide our findings.

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

It depends on the unit and scope of work. We provide an estimated timeline after initial evaluation.

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

Repair Process

Once a valve arrives, we tear it down fully, examine key surfaces, and replace worn or damaged parts using components we stock in-house, cutting out OEM lead times.

  • 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.
  • Cleaning: Units go through a mineral bath, with ultrasonic cleaning used for delicate internals.
  • Leak and Pressure Testing: The reassembled unit is leak-tested and pressure-tested to verify it meets published specs.

Leak and Performance Testing

NC Servo operates thirteen in-house 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 functional testing verifies consistent performance.

MOOG 77-128 Specifications

Every MOOG 77-128 we service is tested under real-world conditions. Our diagnostics verify performance against published specifications. Technical diagrams and Performance data are available for purchase upon request.

Repair, Rebuild and Exchange Options

Beyond standard sales, we offer specialized repairs for your MOOG 77-128 unit. Our teardown process includes leak testing and bench testing, using only new replacement components.

Maintenance Tips

  • Perform fluid analysis to detect contamination early and prevent system damage.
  • Store spare MOOG 77-128 valves in a clean, dry environment to prevent corrosion and contamination.
  • Check system pressure regularly to verify it stays within the MOOG 77-128 rated operating range.

Need Your MOOG 77-128 Back Online?

Request pricing, availability, and turnaround for your MOOG 77-128. NC Servo provides independent repair with a 1-year warranty. Contact us to schedule 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.