18.104.22.168.4 Filling the Buffer With Oil
After filling the buffer with oil, the procedure outlined below shall be followed to ensure that a constant oil level has been established.
(a) The buffer shall be fully compressed at slow speed, and shall then be allowed to return to its fully extended position and remain there for at least 10 min. The oil level shall then be checked.
(b) If the oil level as previously determined has changed, due to the elimination of entrapped air or due to the retention of air under pressure within the buffer, the change in level shall be noted and the procedure repeated until a constant oil level is obtained when the buffer is in its extended position.
(c) If the oil level tends to remain above the level to which it was filled, the air vents, if provided, should be checked for obstructions.
(d) When a constant oil level has been established, the level shall be adjusted to the manufacturer's lowest gauge line, and the exact level noted and recorded before making the drop tests hereinafter specified.