KPMI, custom valve guide seals. PTFE

Solid PTFE valve stem seal, with metal band and retaining spring. Stem diameter: 5/16" (0.311"). Valve guide diameter: 0.415". Overall seal length: 0.517". Seal outer diameter: 0.510". Kibblewhite Precision Machining custom valve stem seals are a quality product and suitable for any custom application.
Note: The valve stem diameters mentioned below are for reference only.
- 36-84 B.T. = 3/8" (.3750") - 57-83 XL intake = 0.3090" - 57-83 XL exhaust = 0.3384" - 84-04 B.T.; 86-03 XL = 5/16" (.311") - 05-16 TCA/B; 04-22 XL; 08-12 XR = 7mm (.2760") - 02-17 V-Rod = 6mm (0.2345") - 17-24 M8 = 6mm (0.2345")
Installation note:
PTFE valve guides require a different fitting technique than 'regular' or non-PTFE valve guides, due to the PTFE material. They are typically 0.020” (0.50mm) smaller than the valve stem and the top of the guide they are designed for.
- The top of the guide must have a good chamfer.
- The valve stem must have a good chamfer, but the use of a mylar seal installation protector / installation capsule (501823 green 5/16" / 0.3125", 501824 yellow 11/32" / 0.34375", 501825 3/8" / 0.375") is recommended to ease installation over the valve stem.
- You must roll the seal around the tip of the valve whilst exerting downward pressure to start installation.
- Do not push directly on the top of the seal to fit it into the guide, otherwise it will collapse the sealing area and break the seal.
- A 12mm 12-point socket fits well on the guide step and can be used to push the seal onto the guide until it is fully seated.
The retaining wire around the sealing area and the band around the area that fits into the guide, combined with the hardness of the material itself, make the seal a tight fit and a little more difficult to install than regular Viton seals. PTFE material has no 'memory' and is therefore subject to creep. This creep allows the seal to conform to the mating surfaces. Due to the 'creep' characteristic, the seal relaxes slightly after installation and does not drag on the valve stem as firmly as it does during installation. The dual spring design provides continuous tension on the valve guide and valve stem throughout its service life.


Specifications


Brand
Kibblewhite


Application
Universal


Sales unit
Pack of 8 pcs


Material
PTFE


Packaging weight
0.045 kg


HS Code
84849000


Original name
KPMI, custom valve guide seals. PTFE