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Valve dimensions

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Fig 1: Valve Dimensions
GW00008214Courtesy of VOLKSWAGEN UNITED STATES, INC.
NOTE:
  • Intake and exhaust valves must not be refaced by grinding. Only lapping is permitted.
Dimension Intake valve Exhaust valve
a = diameter mm 26.8 to 27.0 29.8 to 30.0
b = diameter mm 5.956 to 5.970 5.936 to 5.950
c = mm 96.39 to 96.59 94.79 to 94.99
α = ∠ ° 45 45
CAUTION:
  • Worn sodium-filled exhaust valves must not be scrapped without first being properly treated.
  • Using a metal saw, the valves must be cut in half between the shaft center and valve plate. While doing this, do not come into contact with water. After cutting open valves, throw not more than 10 at a time into a bucket of water. Then, move quickly away, because a sudden chemical reaction will occur during which the sodium is burnt away.
  • The treated parts may then be discarded through conventional disposal channels.