Arrived for single system maintenance. Cleaned and tested flame sensor. Cleaned and tested inducer hose. Noticed blower was dirty and in need of cleaning. Recommend blower cleaning. Customer was interested in going forward with a blower cleaning. Proceeded to clean blower wheel, housing and motor. Noticed a bit of oil coming out of the motor. Run amps on inducer and motor were within ranges. Once cleaned tested unit. Unit working properly on departure.