Bought a boat with a 1999 Merfcury 175EFI on it. The previous owner has been running Mercurcy DFI/Optimax oil in it. Is this the proper oil or should it be using something else? Is this OK or could damage have occured?
Don't know anything 'bout Opti oil. Don't know WHY anyone would run it in anything other than Opti. I wouldn't. I'm sure its pricey. You might wanna go to a Merc or Penn. syn. blend. That would be my choice....................JMO
Just seeing this post. I'd stick with the Optimax oil.
While it can be mixed/used with others, considering the amount of oil you'll consume in a season, why not spent the few extra $$$ considering the cost of $$$ on your engine.
