Precautions - Special Cautions to Ensure the Safe Disposal of Sodium-filled Exhaust Valves (SR20DE & SR20DET engines)
EM-4prose procedureApplies to SR20DE & SR20DET engines (sodium-filled exhaust valves). Identification marks differ: SR20DE = '5J'; SR20DET Type I = '5C'; SR20DET Type II = no mark (0.5 mm hollow in valve lower side).
Special Cautions to Ensure the Safe Disposal of Sodium-filled Exhaust Valves (SR20DE & SR20DET engines)
WARNING
The handling and disposal of sodium-filled exhaust valves requires special care and consideration. Under conditions such as breakage with subsequent exposure to water, the sodium metal which lines the inner portion of the exhaust valve will react violently, forming sodium hydroxide and releasing hydrogen gas which may result in an explosion or fire.
A sodium-filled exhaust valve is identified on the top of its stem as shown in illustration.
DEALER DISPOSAL INSTRUCTIONS
CAUTION
Use approved shatter-resistant eye protection when performing this procedure. Perform this and all subsequent disposal work procedures in an open room, away from flammable liquids. Keep a fire extinguisher, rated at least 10 ABC, in close proximity to the work area. Be sure to wear rubber gloves when performing the following operations.
Dealer Disposal Instructions
- 1Clamp valve stem in a vice.
- 2The valve has a specially-hardened surface. To cut through it, first remove a half-round section, approximately 30 mm (1.18 in) long. Use an air-powered grinder until the black iron color is removed and the silver-colored metal appears.
SEM959C