Yanmar SD20 lower unit

[mullinskeith]

My lower unit has leaked water into the oil reservoir of my SD20 Yanmar sail drive. I'm trying to find out if I can only replace the outer (lower portion) and not have to purchase the entire unit.

[Rapanui]

This is not uncommon. There are 2 oil seals that provided the shaft is in good condition need to be replaced with the boat out. Refill the oil, but to the bottom of the dipstick, no higher. If the shaft is scored, you can use speedy sleeves to give a better seal. That should fix it. Search SD20 on forum for loads of info