I run Mobil1 15-50 in all my boat engines. In the Viper, I run Mobil1 0-40wt

First as others have stated, this claim made by several folks that synthetic oil (much too vague of a label as not all "synthetics are the same") cause or can cause roller lifters to slide instead of roll is utterly false. Engine builders DO NOT know lubricants, they are not chemists, nor blenders or tribologists. PERIOD. They build engines. Some of the worst old wives takes regarding synthetic oils come from engine builders.

You would think the increased lubricity of "some" synthetic oils would make the tale about gliding lifter rollers mean zero wear would occur, when in actuality BBC cams are splash lubed, thus the lobes don't have a large hydrodynamic "wedge" or film of oil all the time like a bearing journal, so damage could occur from a none turning wheel on the roller lifter. However, as roller lifters DO NOT slide or glide in any circumstance other when damaged and locked up mechanically(and definitely not from too much lubricity) this is a moot point.

Synthetics (most) are neither magic nor are they "snake oil" or rather something that will harm your engine. They do certain things better than a conventional oil ie better cold flow, better high heat resistance, less shearing. The real question is, will your application ever use these synthetic oils to their intended potential? Just because it's "synthetic" does not mean it's automatically superior and the ones that are aren't always necessary.

That said, I do prefer and have had great results using certain synthetic motor oils/gear lubes throughout the years. It's all about the best oil for your given application. Like anything it's not a one size fits all kind of thing. In oil blending there is always one area where one strength is lessened to gain something in another. It's about optimization for the given application and what the blender feels is the correct formula. Oil is much more complex than most realize. Good luck

Good job.

Ken

Not trying to highjack but wondering......what kind of oil change interval is everyone going by?

Padraig

When the oil color tells me or once a year...which ever comes first.

Some boats, the smell (fuel dilution) tells me also...but they color too.

The only true way to know would be a UOA (used oil analysis). This will give you stats on the oils condition from contamination to TBN(total base number) and in a marine motor especially, fuel dilution. Unfortunately the color of oil tells you nothing about its condition/reserve capacity.

I use Blackstone laboratories. After a few changes and UOA's with a specific brand and grade, you can then establish an appropriate service interval. Most change oil much too often. This can actually cause increased chemical "wear".

Great comments!

What about the oil ratings for marine engines, doesn't the merc oil has something on the label specific for marine that the Mobil one does not (I think for anti corrosion) I think it is FC-W

http://www.nmma.org/certification/ce.../oil/fc-w.aspx


I would prefer to use mobil one, I use that in all my cars, and its easy to find (and once in a while even on sale!)

FC-W was a classifaction born for modern 4 stroke outboards.

Please explain "increased chemical wear".

Thanks,

Padraig

What Mr. Nobody said lol. All I ever used was synthetics in my ZZ502 and then my 557....never any issues.