Shifting from Synthetic to Mineral oil on a 90HP Mercury Optimax

[pedroarana]

I just purchased a brand new Mercury 90HP Optimax 2-Strokes engine and started using Mercury synthetic oil since the first day, however due to the difficulties in obtaining this oil in south america, I wonder if I could switch to Mineral oil and what would be the procedure for doing it (Could we mixed both oils or do we require to empty the synthetic oil before). Engine is currently about 70 hours of use.

 

[gss036]

Re: Shifting from Synthetic to Mineral oil on a 90HP Mercury Optimax

Mineral oil? I have never heard of that even for the old technology 2 stroke engines. I would try to find a tcw3 blend before using mineral oil, I just don't think you would get enough lubercation as this engine does not inject oil like the standard 2 stroke engines.

 

[jeff_smith_0423]

Re: Shifting from Synthetic to Mineral oil on a 90HP Mercury Optimax

I believe he's referring to what we call "dino-oil" around here - a conventional TCW3 oil. I wouldn't run anything other than the manufacturer recommended oil in that motor during the warranty period. I believe your choices are Mercury Premium Plus or Mercury DFI oil. Everything I've read says to NOT mix the two - run the existing oil out of the motor first.