Oil filter need

I have a Silver edition B&S 17.5 hp engine on my Sears Craftsman riding mower. I am trying to service the engine and believed I needed to install a new oil filter cartridge. The owners manual check list says to change this part after 50 hours operation or annually. I ordered the part from Manage my Life (Sears org?) and received it. For the life of me I cannot find where the current original oil filter is installed on the engine. The picture in the owner manual shows it under the carburetor below the fuel line feed to the Carb but on my engine there isn't a oil filter there. I've looked everywhere. I removed the plastic cover over the engine and no filter. There isn't one near the oil drain plug nor under the frame.

Is it possible this engine doesn't need a filter or is it built in and not accessible?

I can't find the oil filter on the parts listing and may have gotten the part number 492932s from the manage my life people customer serv. rep.

Can anybody help me with this question.