Pump oil question

[Corgi Mom]

Hello. I have a ShinMaywa 50CR2.15S Pond & Waterfall Pump. The manual says to replace the oil every year. For the life of me I cannot figure out where the oil plug is. All I see are bolts. Can anyone help? Thank you.

 

[Mmathis]

Is there a diagram included with the manual? Have you done an internet search?

 

[Mmathis]

Starting on page 14…..

https://cdn.shopify.com/s/files/1/2394/4493/files/ShinMaywa_Norus_Lightweight_Submersible_Pumps_Instruction_Manual_PDF.pdf?v=1645852513