Gene Kearns wrote:

On Fri, 19 Dec 2003 19:34:20 -0500, Harry Krause
wrote:


The service manual for my Yamaha F225 only mentions using ordinary
four-cycle engine oil, never a four-cycle oil by brand. I have not come
across any references to non-dino oil, either. And Yamaha, like every
other outboard maker, has its own private-label oils.

Ditto my Suzukis.... except they do label their own brand.

I did, however, call Suzuki about using synthetics and they didn't
recommend them. When I reminded them that synthetics and dino oil all
had to meet the same SAE and API specs and that none of their
literature led me to believe otherwise.... and thus, "Why not?" They
backed off and said that synthetics might actually be a better oil,
but they had no data, so were telling people, "not recommended."

Some people seem not to realize that some of this data emanates not
from Engineering, but from Sales and Legal....


That seems logical, but I really wonder about the assumed benefits from
synthetic oil, especially if you are supposed to change it at the same
regular intervals as dino oil. We changed the oil at 10 hours in our
Yamaha and then at 50. Fifty seems a reasonable interval for a gas
engine in pleasure boat service.

Interestingly, I haven't really come across a customer service line at
Yamaha similar to the one I called at Mercury. I can't say I've looked
all that hard, but with Merc, it was easy to find. Yamaha doesn't seem
to encourage such connection.

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