Sodium Filled Valves

• If you don't know what type of exhaust valves you have, do not start your engine!

Detecting with Heads off

Inscriptions on Stem of Sodium-filled Valves, John Titus photograph

The original valves may break

There is an inscription on the stem of the valve.

• If the following inscriptions are present:
• ELBMFS -- Eaton Livia Bi Metal Filled Sodium
• ELBMSTFS -- Eaton Livia Bi Metal Stellite Filled Sodium

You have sodium in your valves. -- Replace ASAP.

What happens if valve breaks

Detecting with Heads on

• If you don't remove the heads but remove the tappets and shims you can put a magnet on the valve stem.
  • If the valve stems are completely nonmagnetic they are stainless.
    • Therefore are not the OE sodium filled valves which were made of a magnetic alloy.
  • If they are magnetic they might be sodium filled or they might be solid, but of a magnetic alloy.
    • Some of Andrew's early solid valves are slightly magnetic.
    • His later ones were completely non-magnetic.
    • You may be "reading" some magnetism from the keepers, which are iron.
  • The sodium valves are carbon steel which is really magnetic.

Reconditioning Heads

• Replacement valve guides (made from manganese-bronze are available from SI Valves in California)

See also

• Danger
• Engine Weaknesses
• Purchase Advice
• Rebuilding An Engine