Mercury Oil Filter and Fluids in a 2005 15HP Nissan 4 Stroke and MAiden Voyage Thoughts

Greetings from Grosse Ile Michigan!

I just replaced my lower unit lube and engine oil in my NSF15B2EF1 with Quicksilver High Performance 90 Wt Gear Lube and Quicksilver 4 Stroke Outboard Oil (10W-30). Also, I used the Mercury oil filter for their current small 4 Stroke outboards, which was the exact size as the one on the motor. I bought the motor used, and the old oil filter was painted black. I am wondering if I just replaced the factory oil filter which was on very tight, and required big channel locks to remove. Thoughts?

Motor runs great on my 1976 14ft Mirrocraft. I was thinking that 15HP would be underpowered, but it really gets up and goes!

Yes, the Merc filter will interchange (the Merc motors are Tohatsu builds). There is a Factory filter wrench (cap type, with a 3/8 ratchet drive hole) that will help get a recalcitrant filter off. They do not need to be on more than very snug (just like for a car), but sometimes, some owners put them on too tight. Your lubes should be fine. Oil specs are not a big deal, as long as the motor oil is 10w-30, FC-W rated, non-synthetic. For the LU lube, any SAE 80/90 that is for hypoid gearing (not type C lube) is fine.

Thanks Paul. The Merc lower unit lube is 90 Weight according to the label, and not 80/90. I am temped to replace it with some Pennzoil GL-5 80/90 if you think that there is any reason for a possible problem.

Not a problem. Run the Merc lube. You can d/l a copy of your owner's manual at http://www.nissanmarine.com/tech_talk/owners_manuals.html and thet will detail the "approved" lubricants. Likewise, be sure to review the specific things that are required with a modern, EPA-rated outboard.

Use 10w-30 FC-W rated non-synthetic oil.
Never overfill the oil (not even a drop).
Don't run gas over 30 days old.
Run the carb out at the end of every day.
If reasonable to mount, run a water separator.

what's wrong with synthetic oil?

Synthetic crankcase oils will promote "making oil" see the FAQs across the Internet boards for a discussion of that. Synthetics for the LU are OK, but typically not worth the $$, unless in severe loading, such as racing.