{"id":46685,"date":"2025-06-16T19:10:00","date_gmt":"2025-06-16T19:10:00","guid":{"rendered":"https:\/\/ncservo.com\/?post_type=product&#038;p=46685"},"modified":"2026-03-25T14:59:01","modified_gmt":"2026-03-25T14:59:01","slug":"moog-d631-398c","status":"publish","type":"product","link":"https:\/\/ncservo.com\/.wp-toolkit_m\/product\/moog-d631-398c\/","title":{"rendered":"MOOG D631-398C"},"content":{"rendered":"<div id=\"wb-what-we-do\" class=\"wordbank-container\">\n<h2>How We Repair Your Unit<\/h2>\n<p>We specialize in the overhaul of your MOOG D631-398C, including the replacement of all necessary seals and worn components.<\/p>\n<\/div>\n<div id=\"wb-why-us\" class=\"wordbank-container\">\n<h2>Experience and Warranty<\/h2>\n<p>NC Servo Tech operates independently, so we&#8217;re not tied to manufacturer delays or restrictions. That means more flexibility when your system is down.<\/p>\n<p>17,000+ valves in stock including MOOG D631-398C exchange units<\/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\">Can I request rush service on a repair?<\/button><\/h3>\n<div id=\"faq-content-0\" class=\"faq-content\">\n<p>Rush and priority service options exist. Availability depends on current workload, so contact us early.<\/p>\n<\/div><\/div>\n<div class=\"faq-item\">\n<h3><button aria-expanded=\"true\" aria-controls=\"faq-content-1\">Can this unit be repaired even if I don&#8217;t know the full model number?<\/button><\/h3>\n<div id=\"faq-content-1\" class=\"faq-content\">\n<p>Yes. Our technicians can often identify units based on photos, dimensions, or manufacturer markings. Send a photo before shipping to speed up intake.<\/p>\n<\/div><\/div>\n<div class=\"faq-item\">\n<h3><button aria-expanded=\"true\" aria-controls=\"faq-content-2\">Do you require the unit to be cleaned before shipping?<\/button><\/h3>\n<div id=\"faq-content-2\" 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-3\">Is any kind of warranty included with the service?<\/button><\/h3>\n<div id=\"faq-content-3\" class=\"faq-content\">\n<p>All repairs come with a 12-month warranty on parts and labor. Contact us for specifics on your unit.<\/p>\n<\/div><\/div>\n<div class=\"faq-item\">\n<h3><button aria-expanded=\"true\" aria-controls=\"faq-content-4\">Is it helpful if I include photos before sending the unit in?<\/button><\/h3>\n<div id=\"faq-content-4\" class=\"faq-content\">\n<p>Photos help us confirm the unit type and speed up intake. You can upload them through our quote request form.<\/p>\n<\/div><\/div>\n<\/p><\/div>\n<\/div>\n<div id=\"wb-process\" class=\"wordbank-container\">\n<h2>Disassembly and Rebuild Procedure<\/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>Leak and Pressure Testing: The reassembled unit is leak-tested and pressure-tested to verify it meets published specs.<\/li>\n<li>Seal and Gasket Replacement: Worn seals and gaskets are replaced with new components during every rebuild.<\/li>\n<li>In-House Parts Sourcing: Many repairs use components sourced from our inventory of 17,000+ units.<\/li>\n<li>Cleaning: Units go through a mineral bath, with ultrasonic cleaning used for delicate internals.<\/li>\n<\/ul>\n<\/div>\n<div id=\"wb-testing\" class=\"wordbank-container\">\n<h2>Diagnostic Testing<\/h2>\n<p>We carry out full diagnostics on every valve, including flow gain, leakage, pressure shift, and frequency testing. Our test facility supports performance logging and report generation. Our performance testing verifies consistent performance.<\/p>\n<\/div>\n<div id=\"wb-industry-focus\" class=\"wordbank-container new-dynamic-section\">\n<h2>Where the MOOG D631-398C Is Used<\/h2>\n<p>Our reliable repair services for the MOOG D631-398C are trusted across various sectors including Steel &#038; Metals, Power Generation, and Oil &#038; Gas. We understand the unique demands of valves in these environments.<\/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 reconditioning for your MOOG D631-398C unit. Our disassembly process includes bench testing and spool evaluation, using only new 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 D631-398C services, NC Servo Tech targets quick resolution with typical lead times of 2 to 3 weeks. Benefit from our responsive technical support to keep your systems running smoothly.<\/p>\n<\/div>\n<div id=\"wb-inventory\" class=\"wordbank-container new-dynamic-section\">\n<h2>Stock Availability<\/h2>\n<p>With more than 17,000 valve units in inventory, we can often provide faster turnaround by sourcing parts in-house rather than waiting on OEM lead times.<\/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>Keep hydraulic fluid clean and at proper levels for consistent valve operation.<\/li>\n<li>Conduct thorough visual inspections for wear or leaks during routine maintenance.<\/li>\n<\/ul>\n<\/div>\n<div id=\"wb-cta\" class=\"wordbank-container\">\n<div class=\"cta-section\">\n<h2>Get a Free Evaluation for Your MOOG D631-398C<\/h2>\n<p>Request pricing, availability, and turnaround for your MOOG D631-398C. NC Servo Tech provides hands-on repair with a 1-year warranty. Contact us to request 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>Your MOOG D631-398C is essential equipment. Our technicians repair and test every unit on dedicated hydraulic test stands before it ships back to you.<\/p>\n<\/div>\n","protected":false},"featured_media":57759,"template":"","meta":[],"product_brand":[494],"product_cat":[2425],"product_tag":[152],"class_list":{"0":"post-46685","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_brand-moog","7":"product_cat-moog-hydraulic-valves","8":"product_tag-valve","10":"first","11":"outofstock","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 D631-398C Valve Repair | NC Servo<\/title>\n<meta name=\"description\" content=\"NC Servo repairs your reliable, fast servo valve repair for your MOOG D631-398C. Teardown and bench testing included. 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