Oil for yanmar leg SD20

duckingswan

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I have tried to find the correct oil 10W30 as recommended by yanmar, but I cannot find a supplier, does any one know of an alternative oil that would be ok and not damage the unit?
 
Not a complete answer but I found the technical dept of Morris Lubricants helpful in finding an oil for my Yanmar 4 cyl engine.

They supply by post if req.
 
I have tried to find the correct oil 10W30 as recommended by yanmar, but I cannot find a supplier, does any one know of an alternative oil that would be ok and not damage the unit?

While you might have difficulty in finding a 10W 30 oil you will easily find 5W30 oils..
The 10W and 5W part of the the viscosity grading applies to the flow and pumpability characteristics at extremely low temperatures ( -20 and -25 C ) and are therefore of little concern to you

The second figure is the viscosity when hot . At 100 C a 5W30 oil has the same viscosity as a 10W30 oil.


What have you got the SD20 connected to? For the YM engine / SD combo I have the recommended oil is 80W90 or 90.

Richard

Presumably to a 1GM10

https://www.yanmar.com/media/global...ulsion/operationmanualgears/SD_OM_27MAR09.pdf
 
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The recommended gear oil in the manual for my SD20 is SAE90 or SAE80/90 multi grade. Check your handbook. The multi grade is available at Halfords.
 
The recommended gear oil in the manual for my SD20 is SAE90 or SAE80/90 multi grade. Check your handbook. The multi grade is available at Halfords.

but presumably fitted to one of those engines where SAE80W90 or SAE90 is recommended in the Yanmar manual I gave the link to earlier !

I guess the OP probably has done as you suggested and discovered that for his application 10W30 is the recommended oil
 
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Presumably to a 1GM10

Yes. The poor little 1GM struggles with a drive designed for engines much more powerful that its brave 8hp! The lighter oil is essential to avoid power losses. Definitely NOT a case where "any gear oil will do" - only the one recommended.
 
Yes. The poor little 1GM struggles with a drive designed for engines much more powerful that its brave 8hp! The lighter oil is essential to avoid power losses. Definitely NOT a case where "any gear oil will do" - only the one recommended.

Wow. Could we finally have a marine application for fully synthetic multi grade ? I doubt the oil ever gets warm with such a large drive immersed in cold water and carrying less than 8 horse. The 0W could be really useful in minimising power loss
 
Wow. Could we finally have a marine application for fully synthetic multi grade ? I doubt the oil ever gets warm with such a large drive immersed in cold water and carrying less than 8 horse. The 0W could be really useful in minimising power loss

I was thinking along similar lines, although I would hesitate to stray from the recommended viscosity. For an application that in higher power versions requires a heavy gear oil I would suggest using the best available.
 
Apologies for thread drift ....... but you could make that into a lovely Disney film. I can feel the tears welling-up already. :sorrow:

Richard

Yes, I could see that - probably work a tin of spinach into the scene somehow!

Great little engine, but produces so little power at low revs that the saildrive version also had an interlock to prevent the alternator from charging on start up. Happy memories of the one in my heavy old wooden boat driving a 15" prop through a 3:1 gearbox and getting 5.5 knots with it running close to its 3600 rpm maximum. Real little giant killer. The saildrive version was not a success, but fortunately new boat sizes moved up requiring more hp so few were made.
 
I finally located 20 litres of 10w30 in a agricultural supplier for 50 quid, I now have enough for 8 years, yes my 1 gm had a oil sensor that knocked the alternator off until it got hot,the lug corroded off and it wasn't until weeks later that , when it wudnt start that it was traced , apparently it was for the Scandinavian region, so that was bypassed,
Thanks for reply from all
 
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