KEY (P/N MS-13997-3) - New Surplus

The MS-13997-3 is a steel exhaust valve keeper key for aircraft piston engines, securing the valve stem within the spring retainer assembly. This Military Standard MS13997-compliant component prevents valve stem rotation and maintains proper valve alignment during engine operation. Cross-referenced to Lycoming 17C21191, it's used in Lycoming exhaust valve assemblies across various piston engine models.

Installation requires positioning the keeper key with the valve spring retainer per the applicable engine maintenance manual and illustrated parts catalog. Verify part eligibility for your specific engine model before installation.

What is the KEY (P/N MS-13997-3)?

The MS-13997-3 is a steel exhaust valve keeper key for aircraft piston engines, securing the valve stem within the spring retainer assembly. This Military Standard MS13997-compliant component prevents valve stem rotation and maintains proper valve alignment during engine operation.

What conditions is the MS-13997-3 available in?

The MS-13997-3 is currently available in the following conditions: New Surplus. Each condition reflects the part's maintenance history and certification status per FAA standards.

How do I get pricing for the MS-13997-3?

The MS-13997-3 requires a custom quote. Submit a Request for Quote (RFQ) through our website or call our sales team at (904) 998-9101 for immediate pricing assistance.

Do you offer expedited shipping for the MS-13997-3?

Yes, we offer same-day processing on in-stock items and provide 24/7 AOG (Aircraft on Ground) support for urgent needs. Standard, expedited, and overnight shipping options are available.