need 4stroke help

Russell Guelfi · Sep 23, 2011

Is it OK to substitute Diesel motor oil for 4 stroke outboard motor oil Had service done and they said it is better oil?

EMYancey · Sep 30, 2011

I can't imagine using any oil that doesn't meet the manufacturer's specifications. Diesel motor oil has a whole different additive chemistry.

briscoe · Oct 28, 2011

Go to this site. I agree with Yancey, there are a lot of differences in Diesel and engine oil, especially OB motor oil specifications.
Manual calls for API classification SE, SF, SG, SH, SJ. SAE 10W-40

http://www.dummies.com/how-to/content/engine-oil-the-difference-between-gasoline-and-die.html

francisleo4 · Nov 6, 2011

hi... the proper engine oil is SAE 10W-30 or 40 for outboard motors.