I am going to be changing the oil on my 97 525 sc's. I just got the boat so I need some advice. The old owner said he was running synthetic and lost a lobe on the cam. He said he had the top ends rebuilt and switched to a straight 40 weight. So what oil (Brand/Weight) do you guys recommend? Also does anyone have a good place that I can get the oil and filter from? Does anyone know what filter (part number) I need? Thanks

your merc dealer!

Read the topic "Marine lubrication" it may shed some light on the subject. I run a WIX 1060R filter with Mobil 1 V twin oil. There are many opinions on oil and filters, run what you feel comfortable with.

I always ran 15-50 Mobil 1 in my 525sc every 25-30 hrs. Cam was still perfect at 350 hrs when I upgraded it to a roller cam and lifters looked perfect as well.

Make sure you suck the oil out of the blower and change that too. My book from merc says you can run Hi-perf gear lube. I run 75W90 Royal purple, same as the drive.

just run some good 20 - 50 dino oil or spend the $ on some synthetic or merc oil

all you need to know tuff guy..
you will have all the answers if you can read all this

http://www.offshoreonly.com/forums/s...ht=lubrication