Drain all the oil

[Cambo]

Does anyone know the bolt size for the oil drain . It would be great to replace the bolt with one of these hook a hose up and suck out all the oil

http://www.fumotousa.com/parts.php?partnumber=39

 

[zipper]

This thread references 8mm washer, but not any pitch or specific thread. https://jetboaters.net/threads/oil-change-on-mr-1-how-to-perform-a-complete-drain.3805/