I am not trying to get a thread started that will be moved to the politics/religion section!
My Crusader 454s were fed no name 5W30 before me and I continued that for the last two seasons. Recently I made the mistake of looking at what others have been using for their gas engines including the manufacturer’s recommendation and some rebuild shops. I searched the bertram31.com index too.
Clearly there are strongly held opinions and to a certain degree there is meaningful change as the brands alter the additives in their products. New considerations include using partially recycled oil.
So fresh 5W30 frequently or do you recommend something else? Would anyone recommend the partially recycled oils?
As long as it meets the correct standards I'll pretty much use anything but Castrol in the boat motors. But I do keep with the major name brands, not that the others may not be good...just for a few bucks I have a clear conscience.
I stay away from Castrol as their product breaks down faster in my boat motors then any other brand. Soon as it breaks down I start burning oil...and that leads me to do another oil change or keep checking and adding a bit here and there.
If you are using dino oil, you might consider going with a good diesel rated oil even in gas engines. They have more detergents and are generally a more robust oil. Remember if anyone is running a flat tappet engine (probably not likely in a boat) you need to add ZDDP (zinc) as the levels have been lowered in the newer oils. I have personally gone to synthetic. The website Andre posted is very informative, but can be overwhelming!
Now I'm thinking Shell Rotella T 15W40.
I believe my vintage 1992 Crusader 454s are flat tappet engines so now I need ZDDP? Anybody else out there (I can hear the diesel guys snickering...) adding ZDDP?
I've been using Shell Rotella T 15W40 in everything I own for years, gas or diesel with the exception of the Mercedes GL 450 that requires Mobil One to keep the warranty up.
I change oil strictly by engine hours or road miles (and don't cheat there) and not by calendar time as some (the poeple who sell oil mostly) try to con you into doing. My view is dat dere earl sat in de ground for millions of years and didn't go bad, so letting it sit in a diesel generator for a few years ain't gonna hurt nothin'. Yeah, yeah, all that crap about acid forming, etc. is, in my humble opinion pure bullshit as long as you run the engine enough to bring the oil up to operating temp often enough to boil the moisture out of it.
Saves a lot of time, money, and mess not to chase your tail....remember, the enemy of good is better.
One thing to think about if you have not been using 15-40 since new is the detergent effect will loosen carbon deposits and there will be lots of crud set free from an old motor. You will want to do a few low hour oil changes until the crap has been cleared out. You may also find that the cleaning effect causes oil leaks, blow-by and valve problems so it is a risk to put 15W-40 in older motors that have been running non-detergent oils. If you start a gas motor on 15W-40 this is not a problem.
Stephan, I am no oil expert, so I am really passing on hearsay from my mechanics, I run lots of diesel equipment so there is 15-40 around and have used it in the few gas motors that I have. I believe the difference is that since 15W-40 is formulated for diesel engines, it has anti-soot detergents that suspend soot and other particles in the oil which are removed when you change the oil. I don't believe that the 5W-30 would have the same detergent properties.
