anything wrong with mercruiser synthetic oil? Just changed my oil went back with synthetic wondering if I did the right thing? I have 2000 502 mpi.

good oil , merc aint no slouch

The only problem you might run into is burning more oil , when I used it I was burning about a qt. per motor ever 15 hours. I ran into this problem and went back to quicksilver 25w 40 and I dont burn any now.

Anyone ever tried Royal Purpal, is it overated ?

Amzoil and Royal P are great oils, But they cost. I use the
Merc syn and my oil temps run cooler when running hard.
I also change it ever 50 Hours.

My second wkend on merc. syn. my oil temp runs cooler also. I would like to thank evryone for ur comments on this thread. I do think I will stick with th synthetic oil.