502MAG EFI Synthetic oil
 

What atre the pros and cons on synthetic oil in a boat...anyone??
What brand has anyone out there used and had sucess with?
Thanks,
Mike

Search function is your friend. It will lead you to what you are looking for.

Get a case of 15W-40 Royal Purple and be done with it. Your engine will run smoother, last longer, make more horsepower, emit less emissions AND if you're ever unfortunate enough to have salt water injestion, you have a good chance of saving the engine.

I idled in from the ocean for 2 hrs. with a broken oil pump shaft. The engine never seized and is still running today in a 27' Baja Shooter. The only reason I changed the rod and main bearings was because I had it already apart and I didn't want to take a chance. The oil pump failed at 275 hrs. and I ran the RP from 30 hrs.

i use the mobile 1 delvac in my motors that are the same as yours. i've never tested an oil in service that was better than the mobil 1 full synthetic products . and you can buy it anywhere.

there are no magic oils. the synthetics are better in all respects than the non synthetics and the only difference between the true full synthetics is the additive packages and the fractional chemical makeups.

your motors, like mine, require nothing at all special in an oil. the components are good and the stresses are nothing special. the injection will keep the oil clean for a long long time as long as you keep the water temps high enough to get into closed loop.