Begin the system diagnosis by reviewing the Disassembled Views , Engine Component Description , Lubrication Description , and Drive Belt System Description . Reviewing the description and operation information helps you determine the correct symptom diagnostic procedure when a condition exists. Reviewing the description and operation information also helps you determine if the condition described by the customer is normal operation. Refer to Symptoms - Engine Mechanical in order to identify the correct procedure for diagnosing the system and where the procedure is located.