Question 9General Subjects - 1st Asst/Chief

The correct answer is B) spring force. In a compression type automatic grease cup, the lubricant is forced into the bearing by the spring force within the grease cup. The spring provides the necessary pressure to push the lubricant through the fitting and into the bearing, ensuring proper lubrication. The other options are incorrect because: A) a zerk fitting is used to introduce grease manually, not in an automatic system; C) gravity flow alone is not sufficient to provide the necessary pressure to force grease into a bearing; and D) a pressure gun is used to manually apply grease, not in an automatic system.