Synthetic Oil in Marine Diesels?
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I think you'll find lots of discussions on this topic in the archives. Aside from the technical recommendations from manufacturers, I change my oil in the fall and in the spring to eliminate things like acid buildup, etc. In the average marine diesel, you will want to change the oil out for those reasons, long before synthetic would have "worn out". That would seem to be a fair bit more expense, for little effective benefit.
2 cents.
Chris
2 cents.
Chris
Iv'e never really understood why people don't want to follow the manufacturer's recommendations. At least contact them and see what they say about synthetics. It's possible that it would be fine if you changed the oil to their recommendations. They may have not wanted to test a variety of synthetics to be able to make a recommendation or they don't think there is an advantage.
I don't think running synthetic oil is good for new engine. The rings don't set. Synthetic only prolongs the change interval not any better lubricant. May void the warranted.
In some places, it cost almost 50% more. I would just change more often.
In some places, it cost almost 50% more. I would just change more often.
I have always heard
I don't know that synthetic would have much benefit if any. Never tried it. BUT I have seen in multiple places where it should not be mixed. That, from all I hear, is a no no.
I don't know that synthetic would have much benefit if any. Never tried it. BUT I have seen in multiple places where it should not be mixed. That, from all I hear, is a no no.
Westerbeke / Universal advise that if using a synthetic oil the engine MUST be broken in with conventional oil first.
They also advise that the oil change interval does NOT change if using a synthetic. This means you still change it at the same hours as conventional oil but pay about double or more for the synthetic.
Also there is risk of creating leaks in older engines that have been run on conventional oils. I had this bite me in the arse on three vehicles before I smartened up....
Synthetic gets expensive when you consider many diesels run 15k hours+ on conventional oil. I have numerous commercial customers with over 10k engien horus and they all run Rotella T or Delo conventional oil. 10k hours on a sailboat, at 100 hours avg per year, means your engine lasts 100 years + using just conventional oil.
Also consider that "Million Mile Joe" drove a run of the mill Honda Accord 1,000,000 miles on the original, un-rebuilt, engine and transmission using nothing but conventional oil & regular transmission fluid.. If a basic Honda accord can go 1,000,000 on conventional oil........
There are many other things you can do for your engine to get the most out of it that will do far more for longevity than conventional vs. synthetic.. Food for thought..
They also advise that the oil change interval does NOT change if using a synthetic. This means you still change it at the same hours as conventional oil but pay about double or more for the synthetic.
Also there is risk of creating leaks in older engines that have been run on conventional oils. I had this bite me in the arse on three vehicles before I smartened up....
Synthetic gets expensive when you consider many diesels run 15k hours+ on conventional oil. I have numerous commercial customers with over 10k engien horus and they all run Rotella T or Delo conventional oil. 10k hours on a sailboat, at 100 hours avg per year, means your engine lasts 100 years + using just conventional oil.
Also consider that "Million Mile Joe" drove a run of the mill Honda Accord 1,000,000 miles on the original, un-rebuilt, engine and transmission using nothing but conventional oil & regular transmission fluid.. If a basic Honda accord can go 1,000,000 on conventional oil........ There are many other things you can do for your engine to get the most out of it that will do far more for longevity than conventional vs. synthetic.. Food for thought..
oil change interval
Any reputable source will recommend changing the engine oil every season, assuming use, due to chemical changes in the oil caused by use. Oil is preferably changed at winterizing so caustic fluids are not stored in the engine attracting moisture. An extra couple dollars per season for Amsoil in an Atomic 4 is worth the benefits.
Any reputable source will recommend changing the engine oil every season, assuming use, due to chemical changes in the oil caused by use. Oil is preferably changed at winterizing so caustic fluids are not stored in the engine attracting moisture. An extra couple dollars per season for Amsoil in an Atomic 4 is worth the benefits.
The cummins customer web site states that the only situation that would be benefical to the engines they produce regarding synthetic oils is in extreme frigid temperatures where the temps stay below -10 F .Other then those conditions synthetics perform no better than conventional petroleums and are not economically competetive.So you would think if cummins was warrantying these engines and synthetics did miracles they would want to reccomend there use, but they don't so take that for whatever its worth.
Synthetic oils work well in transmissions, pumps, transfer cases and differentials as they are sealed in a clean environment but in an engine where combustion residues tend to contaminate the oil the extra expense is not warranted.
Shell Rotella T, 15W45. All the oil you'll ever need, in just about any 4 cycle engine.
The only advantage a synthetic would have is in sub zero temps. But as only a fool would try starting a diesel at those temperatures without preheating it first, its still not necessary.
You cant extend oil changes just because you use synthetic, regardless of what any oil manufactures says to the contrary. Read the owners manual. Not one single manufacturer allows extending oil changes based on oil type.
This guy owned two Mercury Cougars with BMW diesels, tried to tell me the engines were no good, he had valve trouble with both at 100K miles. One day he sees my Mercedes, said he owned one once, also not any good, he had valve trouble at 100K miles. Then one day were talking and he tells me hes a big Mobil 1 fan. I say, "you do the 25K mile oil change thing?" He said he did. He said he did both those bimmers and the Benz that way too. He was a MORON. You have to change the oil folks. He also thought he could run 100 hours on his airplane between oil changes. What a cheap sob. Dangerous too, in that venue.
The only advantage a synthetic would have is in sub zero temps. But as only a fool would try starting a diesel at those temperatures without preheating it first, its still not necessary.
You cant extend oil changes just because you use synthetic, regardless of what any oil manufactures says to the contrary. Read the owners manual. Not one single manufacturer allows extending oil changes based on oil type.
This guy owned two Mercury Cougars with BMW diesels, tried to tell me the engines were no good, he had valve trouble with both at 100K miles. One day he sees my Mercedes, said he owned one once, also not any good, he had valve trouble at 100K miles. Then one day were talking and he tells me hes a big Mobil 1 fan. I say, "you do the 25K mile oil change thing?" He said he did. He said he did both those bimmers and the Benz that way too. He was a MORON. You have to change the oil folks. He also thought he could run 100 hours on his airplane between oil changes. What a cheap sob. Dangerous too, in that venue.
Synthetic oil is more prone to leak than conventional oil. If you want to keep your oil inside the engine, and not all over the inside of your engine room, and beyond, stick with Rotella T.
If you want to chance a little extra lubrication at the risk of leaks, venture into the land of exotic oils and additives.
If you want to chance a little extra lubrication at the risk of leaks, venture into the land of exotic oils and additives.
Thanks for the replies, I couldn't see a benefit either unless they help the top end stay wet when you go to start up after a week or too, all that wear on startup thing.
That's a good idea for engine breakin, I was planning to run synthetic in a new 1049cc high rev gas engine on a turbo, but now I think I will use conventional for the first500km
That's a good idea for engine breakin, I was planning to run synthetic in a new 1049cc high rev gas engine on a turbo, but now I think I will use conventional for the first500km
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