I need to add motor oil to my pressure washer. I can find my manual for Briggs & Stratton Troy-Bilt Pressurer Washer - 3000 PSI 7 GPM 7.25 HP OHV. It looks like 3 places to add oil. Please tell me where to add motor oil. There are 2 yellow caps facing each side of the motor and one white cap in the front facing up. Which one do I put the oil in. Thank you, Stephanie O'Neal