{"id":52182,"date":"2025-06-16T19:59:00","date_gmt":"2025-06-16T19:59:00","guid":{"rendered":"https:\/\/ncservo.com\/?post_type=product&#038;p=52182"},"modified":"2026-03-31T18:57:00","modified_gmt":"2026-03-31T18:57:00","slug":"moog-d631-335c","status":"publish","type":"product","link":"https:\/\/ncservo.com\/.wp-toolkit_m\/product\/moog-d631-335c\/","title":{"rendered":"MOOG D631-335C"},"content":{"rendered":"<div id=\"wb-overview\" class=\"wordbank-container\">\n<h2>Overview<\/h2>\n<p>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.<\/p>\n<\/div>\n<div id=\"wb-why-us\" class=\"wordbank-container\">\n<h2>Independent Repair Facility<\/h2>\n<p>NC Servo Tech specializes in both valves and electronic controls, which lets us operate without the delays of OEM service centers.<\/p>\n<p>50+ years of expertise in MOOG D631-335C Valve Repair<\/p>\n<\/div>\n<div id=\"wb-faq\" class=\"wordbank-container\">\n<h2>Frequently Asked Questions<\/h2>\n<div class=\"faq-accordion\">\n<div class=\"faq-item\">\n<h3><button aria-expanded=\"true\" aria-controls=\"faq-content-0\">Will you diagnose the problem before repairing?<\/button><\/h3>\n<div id=\"faq-content-0\" class=\"faq-content\">\n<p>Inspection and root-cause analysis are part of our standard process. We identify the issue before starting any repair work.<\/p>\n<\/div><\/div>\n<div class=\"faq-item\">\n<h3><button aria-expanded=\"true\" aria-controls=\"faq-content-1\">Do I need to clean the unit before sending it in?<\/button><\/h3>\n<div id=\"faq-content-1\" class=\"faq-content\">\n<p>Not required, but removing excess oil or loose debris before packing helps keep things clean in transit.<\/p>\n<\/div><\/div>\n<div class=\"faq-item\">\n<h3><button aria-expanded=\"true\" aria-controls=\"faq-content-2\">Is it helpful if I include photos before sending the unit in?<\/button><\/h3>\n<div id=\"faq-content-2\" class=\"faq-content\">\n<p>We recommend sending pictures, especially if the model number is unclear or there is visible damage.<\/p>\n<\/div><\/div>\n<div class=\"faq-item\">\n<h3><button aria-expanded=\"true\" aria-controls=\"faq-content-3\">What happens if you can&#8217;t fix my unit?<\/button><\/h3>\n<div id=\"faq-content-3\" class=\"faq-content\">\n<p>If a unit is beyond repair, we explain why and can discuss replacement or exchange options.<\/p>\n<\/div><\/div>\n<div class=\"faq-item\">\n<h3><button aria-expanded=\"true\" aria-controls=\"faq-content-4\">How can I tell if my unit is still salvageable?<\/button><\/h3>\n<div id=\"faq-content-4\" class=\"faq-content\">\n<p>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.<\/p>\n<\/div><\/div>\n<\/p><\/div>\n<\/div>\n<div id=\"wb-process\" class=\"wordbank-container\">\n<h2>How We Rebuild This Valve<\/h2>\n<p>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.<\/p>\n<ul>\n<li>Cleaning: Units go through a mineral bath, with ultrasonic cleaning used for delicate internals.<\/li>\n<li>Final Performance Verification: After reassembly, each valve is bench-tested against published performance specifications.<\/li>\n<li>Seal and Gasket Replacement: Worn seals and gaskets are replaced with new components during every rebuild.<\/li>\n<li>Leak and Pressure Testing: The reassembled unit is leak-tested and pressure-tested to verify it meets published specs.<\/li>\n<\/ul>\n<\/div>\n<div id=\"wb-testing\" class=\"wordbank-container\">\n<h2>Testing and Bench Verification<\/h2>\n<p>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.<\/p>\n<\/div>\n<div id=\"wb-service-offerings\" class=\"wordbank-container new-dynamic-section\">\n<h2>Repair, Rebuild and Exchange Options<\/h2>\n<p>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.<\/p>\n<\/div>\n<div id=\"wb-logistics-support\" class=\"wordbank-container new-dynamic-section\">\n<h2>Lead Times and Support<\/h2>\n<p>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.<\/p>\n<\/div>\n<div id=\"wb-tips\" class=\"wordbank-container\">\n<h2>Maintenance Tips<\/h2>\n<ul>\n<li>Schedule preventive maintenance intervals based on duty cycle, not just calendar time.<\/li>\n<li>Store spare MOOG D631-335C valves in a clean, dry environment to prevent corrosion and contamination.<\/li>\n<li>Use only manufacturer-recommended hydraulic fluids to protect internal valve surfaces.<\/li>\n<\/ul>\n<\/div>\n<div id=\"wb-cta\" class=\"wordbank-container\">\n<div class=\"cta-section\">\n<h2>Let Us Repair Your MOOG D631-335C<\/h2>\n<p>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.<\/p>\n<div class=\"cta-buttons\"><a href=\"https:\/\/ncservo.com\/.wp-toolkit_m\/contact-us\/\" class=\"button quote-button\">Request a Quote<\/a> <a href=\"https:\/\/ncservo.com\/.wp-toolkit_m\/moog\/\" class=\"button brand-button\">View All MOOG Products<\/a> <a href=\"https:\/\/ncservo.com\/.wp-toolkit_m\/brand\/moog\/\" class=\"button inventory-button\">Shop MOOG Inventory<\/a><\/div>\n<\/div>\n<\/div>\n<div class=\"disclaimer-section\">\n<p class=\"disclaimer\"><strong>NC Servo Tech<\/strong> 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.<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<div id=\"wb-short-description\" class=\"short-description-container\">\n<p>Trust your MOOG D631-335C repair to a shop that understands servo and proportional valve technology. We repair, test, and document every unit before it leaves.<\/p>\n<\/div>\n","protected":false},"featured_media":57759,"template":"","meta":[],"product_brand":[494],"product_cat":[139],"product_tag":[152],"class_list":{"0":"post-52182","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_brand-moog","7":"product_cat-moog","8":"product_tag-valve","10":"first","11":"instock","12":"shipping-taxable","13":"product-type-simple"},"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>MOOG D631-335C Valve Maintenance | NC Servo<\/title>\n<meta name=\"description\" content=\"Servo valve repair: Durable, warrantied service for your MOOG D631-335C. 50+ years of hydraulic repair experience. 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