Re: Why Doesn't Merc Use Synthetic Oil?
 

Here are some possible oils for boats and their virgin oil analysis. Do a UOA and you can determine what life is left in the oil by looking at viscosity and TBN.

http://home.earthlink.net/~memphis3/boatoilsweb.htm

Re: Why Doesn't Merc Use Synthetic Oil?
 

Merc will start recommending synthetics as soon as they start selling it. ;)

Re: Why Doesn't Merc Use Synthetic Oil?
 

Is this true or not. Once you go synthetic you cant go back???

Re: Why Doesn't Merc Use Synthetic Oil?
 

In all my research about oils this week, a Merc rep told me I need to run the higher weight oil (like Merc oil) because after high rpm runs the oil thins and when dropping to idle rpms it will loose oil pressure with lighter weight oils.

That tells me I'm going to run synthetics for sure. I just bought a case of Amsoil.

Re: Why Doesn't Merc Use Synthetic Oil?
 

An old wives tale.

Re: Why Doesn't Merc Use Synthetic Oil?
 

thanks, keep the comment's coming. I just bought a case of amsoil 2000 20-50 racing synthetic oil today. a real good source told me that merc is using that oil in there new 1050 motor. hope its worth it $$$$$

Re: Why Doesn't Merc Use Synthetic Oil?
 

Mercury has come out with a synthetic oil in mercury branded package it is a red bottle like noted earlier in the post, Aside from this new synthetic. mercury manuals have always stated that if your not going to use their standard oil a split weight 20w-50, that you should run straight 40 weight oil I run Valvoline VR-1 Racing oil 40W in everything from a 3.0 to 900 hp 502

Re: Why Doesn't Merc Use Synthetic Oil?
 

Dusty Times,

Thanks for the info from merc. That is exactly what my engine does. I run straight 30 wt. Maybe I need 40 wt.

I never saw the problem with my factory motor even with knocking rods and merc oil.

Thanks

Re: Why Doesn't Merc Use Synthetic Oil?
 

Actually Mercs standard oil is 25W40 not 20W50 as is their new synthetic.

Re: Why Doesn't Merc Use Synthetic Oil?
 

If Mercury started recommending synthetic oil, How would they sell replacement parts?!