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The proper installation of CHE valve seats is very important to the
longevity and performance of the entire valve train.

  1. Inspect “cylinder head” and remove any debris and burrs.
  2. Measure “cylinder head” seat hole.
  3. Recommended press fit:
    • Ductile Iron seat in cast iron head  = 0.005 / 0.006 inch
    • Ductile Iron seat in aluminum head = 0.008 inch 
    • CA-18 seat in aluminum head          = 0.006 inch
    • X-274 seat in aluminum head          = 0.006 inch
  4. Heat the “cylinder head” to approximately 250 Degrees F.
  5. Cool valve seats. Freeze or colder (less than 32 degrees F)
  6. Put a coat of light oil on the seat O.D.
  7. Using a driver, install the valve seat. Care should be taken to ensure that seat is driven in straight and is completely seated into the “cylinder head”.
  8. Valve seats should now be given a valve job.
  9. If seats are driven in at room temperature with an air hammer, the OD (Outer Diameter) should be polished to minimize material transfer. *

* CHE Precision strongly recommends against this procedure!

NOTE: Under no circumstance should any adhesive, sealant or similar compound be used when installing valve seats. The substances act as insulators and will reduce heat transfer from the seat into the “cylinder head.

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