Oil analysis test results can often be related to engine problems. When the test results of an in-service oil sample exceeds the RECOMMENDED WARNING LIMITS , one or more of the following is usually involved.

• The oil has been contaminated by foreign materials.
• The oil has been in use longer than the optimum period between drains.
• The engine has been operated improperly or under adverse conditions.
• The engine is out of adjustment, has mechanical problem, or is worn out.

The ENGINE PROBLEM CHECKLIST on the following pages can help resolve which of these situations is responsible for the poor oil condition. It gives the primary causes of the poor test results, and suggests specific factors which may be involved.

This CHECKLIST cannot provide recommendations for specific equipment or operation situations. It can provide some general guidelines-suggestions about where to look when problems occur.