what oil you guys running, whats merc recommend and what weight? 94 502 efi's I have no manuals yet

Do a search, LOTSA info.

Lots of oils out there to do a good job and I have tried a lot of them over the years and for stock engines they work just fine. But for the bigger HP engines I have settled on Neo P40 for my 850's and I really like it.

Since I had my first boat in 1987, I've seen where Mercury has recommended straight 40 weight for over 50 degree temps. Now, they also recommend their 25-40 oil. Don't see how you can go wrong with a quality straight 40 weight, though.

I had a engine built bye active engines in ontario at the time he did all merc waranty in ontario he built a omc 460 for me ant recomended castrol 20 50 ive used since, now with new boat and ultra low hours i shouldn't have to worry about rebuilds for some time. so just want to run the right stuff. recently someone also told me i should run straight 40 so im just trying to do some research want to change ool this week sometime before heat kicks in again we have some 60/65 degree days coming up perfect working weather

I use 20 - 50 Royal purple, but as you read there are lots of choices. The most favored, I believe is 20 - 50 mobil 1.


Lots of reading OIL Links:

Start on last page of some and work towards front for current stuff, but read Hydocruiser stuff at beginning.

http://valvoline.com/faqs/motor-oil/...tic-motor-oil/

http://www.offshoreonly.com/forums/g...brication.html

http://www.offshoreonly.com/forums/g...brication.html

everyone will have their own oil they like and are loyal too...
i use Brad Penn - "the green oil"

Lotta info there beyond me, IMO any leading brand is good i run qs in all my cars nevr a issue once i tried penzoil and my car started burning oil switched back to qs never used oil again what weight is best i guess is my question