scope:

Note: Nothing in this standard supercedes applicable laws and regulations.

Note: In the event of conflict between the English and domestic language, the English language shall take precedence.

Purpose. Measure by collected weight, the oil flow rate (Q) due to gravity alone (Procedure A) or due to gravity and absorbed with a special paper (Procedure B) off the valve stem, guides, etc., after ten (10) hours. See paragraphs 5.2.3 and 5.2.4 for procedure usage guidelines. Results (optional) may be converted to a volume per 5.1.2.

Foreword. A function of valve stem seals is to control the passage of oil (flow) between the reciprocating valve stem, valve guide, and the seal lip. Insufficient lubrication leads to abrasion, abnormal valve noise, and in the worst case, valve burnout. Validation of seal design factors is accomplished by precise measurement of oil leakage using actual engine components.

Applicability. Intake and exhaust valve stem seals. After long term engine lab or field testing, leakage can be remeasured.