How to Change the Oil, Filters, and Spark Plug on my Huskee Riding Mower This is something that most anyone can do and it will save you a lot of money. Maintenance you can do for $15. The shop will charge you $75 for the same thing. PS: My camera battery stopped while I was filling the mower with oil but it only took about a quart of oil to fill the engine. Just add a little at a time until it is full.