What Oil for Yanmar (SD 20) Saildrive ?

[svstrider]

I had to pull my cat out to replace the seals on the SD 20 sail drives as water had been contaminating the oil for some time apparently. The mechanic said that the transmission oil that the previous owner had been using was wrong and that I should only use the PROPER Yanmar said drive oil.
Any one agree / disagree. Any reccomendations?
Thanks
Paul

[cat man do]

Originally Posted by svstrider

Any reccomendations?
Thanks

Here you go

[Ram]

i use 80-90w synthic

[hugosalt]

I have been using SAE90 for many years with yanmar dealers blessing...understand that 80-90 is approved as well.
Following is my understanding...not necessarily from yanmar,
synthetic is better for saildrive as it does not break down as fast
if there is any water intrusion.

[Kapitan]

I'd reccomend you some oils but can you give me your engine model

[ggray]

I'll second the synthetic recommendation.
I use Amsoil marine gear lube that they claim can tolerate 10% water. Whether that is true or not, it makes me feel better.

[svstrider]

Originally Posted by Kapitan

I'd reccomend you some oils but can you give me your engine model

Engine is Yanmar 3GM30 and sail drive is a SD20
Paul

[Kapitan]

For your engine - saildrive combination, Yanmar recommends API GL4 or GL5
and SAE 80W90 or 90 degree lubrication oil for the saildrive.