mvweebles
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Rotella fan here too. Only question is which flavor. T5 for my ancient Perkins
Peter
Peter
Oil change
- Thread starter Sharpseadog
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The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
Why are all you guys worried about moisture in your crank case? There is hardly any air movement in ‘ out of the engine oil system. I just don’t see this being as big an issue as people make it out to be. If I do a season of 100 hours , I’m not throwing away good oil . I run it the next season . My boat is only sleeping for 3 months .
I was a T6 guy, but your thread has me reconsidering the T5 (have T5 now as that 8s what I could find in Bahamas 4 months ago)
High Wire
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Rotella. Two years ago (time flies) during the supply chain crisis you couldn’t get any. Now it’s back. Because of that I carry enough oil for a full change of main engine and generator at all times.
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Delta Riverat
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I'm using T4. Should be better than anything they had back in 1979.
But I see T5 is only $3 more a gallon so maybe next time.
But I see T5 is only $3 more a gallon so maybe next time.
The best write-up of marine engine oil I've seen is by Cox Eng.
The takeaways I got from their article...
Modern diesel eng oils are developed for auto / truck requirements and those requirements re emissions systems etc has changed radically in recent decades.
Most of our marine / Yacht engines & requirements have changed little in that same period
Using the latest API grades may not be the best choice for our marine diesels
Use of synthetic oils for marine engines may not be the best choice
I'm a fan of older (API CD) rated straight grade oils as I don't run in cold Wx and removing a portion (10%-15%?) Of the base lubricating oil to accommodate the the multi-vis additives seems counter productive to me.
For the complete article see my Bacchus website (linked in signature) Useful Links section and see the Cox Eng - Oils for Yacht Engines Link
The takeaways I got from their article...
Modern diesel eng oils are developed for auto / truck requirements and those requirements re emissions systems etc has changed radically in recent decades.
Most of our marine / Yacht engines & requirements have changed little in that same period
Using the latest API grades may not be the best choice for our marine diesels
Use of synthetic oils for marine engines may not be the best choice
I'm a fan of older (API CD) rated straight grade oils as I don't run in cold Wx and removing a portion (10%-15%?) Of the base lubricating oil to accommodate the the multi-vis additives seems counter productive to me.
For the complete article see my Bacchus website (linked in signature) Useful Links section and see the Cox Eng - Oils for Yacht Engines Link
rslifkin
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Oil wise, my engines get either Delo or Rotella 15W-40 depending on price and availability. I was using the non-synth versions for a while but switched to the syn blend because they've been so close in price. A couple of the cars and bits of lawn equipment (and the dinghy outboard) have the 5W-40 full synth version in them.
Combustion blowby puts moisture into the crankcase.
Combustion blowby puts moisture into the crankcase.
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DennisB1
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I would recommend an oil analysis to determine if you are doing extend oil changes rather that following the prescriptive approach of once a year or 250 hrs as recommended on the specs for my cat engines. I ran the synthetic diesel oil for two seasons (about 250 hrs) and the test results were the oil tested as new. The oil I use also has high TBN number to counter acid build. If you test you have a basis for making a judgement of continued use or changing the oil. Most of my engine runs are for 2 or more hours which would keep the allow for any free or ingrained moisture to dissipate. The engine room is at a pretty constant temp and a dehumidified keeps the humidity low to assist in reducing or eliminating condensation. My $.02 opinion.
Hippocampus
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Which one the KU06?
mvweebles
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Agree 100%. I don't sweat oil too much, but I also don't hesitate to spend extra money. That said, Walmart seems to be a reliable source of Rotella. Oddly, their diesel oils are sometimes in a different part of the automotive section than their spark-ignition (auto) oils.
When researchin the thread I posted a couple months ago on T5 (hybrid synthetic - my choice going forward) vs T6 (full synthetic) vs T4 (traditional), I watched a couple YouTube videos of older independent truckers - the type who run their own trucks for 1m miles or more - who described how relucatant they were to go synthetic when the oils gained popularity. Their original fear was the oft-cited claim that synthetics and old engines don't play nicely together. But over time, they saw how well synthetics did even in older trucks. They had long since converted to synthetics and would never go back. One guy sort of laughed at himself for the fear-mongering he believed 25-years before.
Peter
Coastal Cruiser
Veteran Member
Three things:
Oil filters have a useful life as well. One may extend the use of the oil (based on analysis) but exceed the useful life of the filter.
When one goes to sell the boat and a potential purchaser asks about oil changes the response will be " I ignored the manufacturer's recommendations and changed the oil based on expert comments I found on the internet". ......That will sell.........
I find it interesting that boaters will spend hundreds of thousands of dollars on a boat yet will try to save a few dollars on oil changes, And BTW- oil analysis isn't free. Re saving the environment by stretching oil changes - proper disposal of the oil will result in it being recycled.
Oil filters have a useful life as well. One may extend the use of the oil (based on analysis) but exceed the useful life of the filter.
When one goes to sell the boat and a potential purchaser asks about oil changes the response will be " I ignored the manufacturer's recommendations and changed the oil based on expert comments I found on the internet". ......That will sell.........
I find it interesting that boaters will spend hundreds of thousands of dollars on a boat yet will try to save a few dollars on oil changes, And BTW- oil analysis isn't free. Re saving the environment by stretching oil changes - proper disposal of the oil will result in it being recycled.
Hippocampus
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Never made any sense to me to change oil and not the filters. Could see if you had a centrifuge to change filters but not the oil. But the other way around never struck me as sensible. Same with impellers. It such a struggle even with an impeller tool to get them out /in and you can damage them I just change them. Agree it’s. $100+ bucks for the big one but that’s the most important one that I never want to fail.
Simi 60
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Oil changes on ours are based, I would assume, on worst case scenario
Example : running at full tits underground in a mine site sucking in lung fulls of coal dust
Based on that and our running at a fast idle with clean air I now do them on litres of diesel burnt, the graphs are in our manual.
That puts us out at around 600 hours and, at that schedule, the old oil coming out still looks as clean as the old oil going in.
Example : running at full tits underground in a mine site sucking in lung fulls of coal dust
Based on that and our running at a fast idle with clean air I now do them on litres of diesel burnt, the graphs are in our manual.
That puts us out at around 600 hours and, at that schedule, the old oil coming out still looks as clean as the old oil going in.
ranger58sb
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Hard to imagine. Their (several versions of) oils meet API specs.
Our engine manufacturer goes a step further, specifying acceptable oils by specific brand/model and for each specific engine, i.e, not just by API specs across the board for all their engines. Rotella T6 (full synthetic) is one of the few on their list for our specific engines.
-Chris
rslifkin
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Appearance tells you a little about soot content, but nothing useful about how much TBN remains, or whether the additives are still doing their jobs and keeping wear down.
Amount of fuel burned is a reasonable metric to go off provided the oil gets hot enough at the speeds you're running.
catalinajack
Guru
Any oil by any major manufacturer is just as good, one for another.
psneeld
Guru
We weren't allowed to use big words or go into deep water in the USCG...
I know a lot of experienced people here are saying no to free water in the engine oil, even me on my oil tests.... but I found plenty under the valve covers occasionally when pulled and online pictures show plenty of milky sludge under valve covers on engines that aren't run much or hot.
An science knows there is tiny amounts in diesel fuel and oils....... so I will let the adults that can use big words argue about it.
rslifkin
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Moisture in oil definitely happens. How much and whether it's a problem depends on both the engine in question and usage patterns. As an example, some engines are very prone to condensation under the valve covers with shorter runs (especially in cool climates), others don't seem to have any such issue.
ronobrien
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A guy at my marina who was a truck service manager got it from an engine manufacturers rep. I didn't get the impression that the guy was selling his own lube product. I need to Q him a little more.
rslifkin
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Newer diesel oils (not just Rotella) no longer contain as much ZDDP as they used to. Still more than most passenger car type oils though. So changes like that might make it less suitable for certain specific applications now and would require a more specialized oil. But any of the major brand HDEO oils (like Rotella) are at least a pretty decent oil and should turn in at least acceptable wear performance in any engine they're suitable for use in.
Years ago, with the move from Low Sulfur Diesel(LSD) to Ultra Low Sulfur Diesel(ULSD), the additive to increase the TBN was lowered since the amount of sulfur in the fuel was decreased, so maybe that is what is being discussed. If so, it is a moot point since with less sulfur in the fuel less additive is needed.
I have been using mostly Shell since the switch to ULSD and my oil analysis has not changed.
Later,
Dan
Nomad Willy
Guru
Hippocampus wrote;
“ Never made any sense to me to change oil and not the filters.”
Some engines have really small filters. I had such an engine. The engine was usually found on backhoes and other similar equipment. A Mitsubishi. I immediately changed to a remote filter and ordered a filter much larger than the original. I reasoned that if a filter was to “fill up” w filtered contaminants it would take almost 3 times as long as w the original filter. Not totally correct as I left some small amount of oil in the system. I may not have dealt myself a 1 = 1 deal but considered that changing the oil and not the filter was far better than not changing the oil at all.
Also in a normal oil change there remains in the engine a considerable amount of oil. And that oil may be in the valleys inside the engine where more contaminants will almost certainly remain after an oil drain. And the same engine when marineized by one or more manufacturers probably often has different size filters. And they may not adhere to the original base engine specifications.
So there’s lots of variations that effect the oil change drill.
“ Never made any sense to me to change oil and not the filters.”
Some engines have really small filters. I had such an engine. The engine was usually found on backhoes and other similar equipment. A Mitsubishi. I immediately changed to a remote filter and ordered a filter much larger than the original. I reasoned that if a filter was to “fill up” w filtered contaminants it would take almost 3 times as long as w the original filter. Not totally correct as I left some small amount of oil in the system. I may not have dealt myself a 1 = 1 deal but considered that changing the oil and not the filter was far better than not changing the oil at all.
Also in a normal oil change there remains in the engine a considerable amount of oil. And that oil may be in the valleys inside the engine where more contaminants will almost certainly remain after an oil drain. And the same engine when marineized by one or more manufacturers probably often has different size filters. And they may not adhere to the original base engine specifications.
So there’s lots of variations that effect the oil change drill.
psneeld
Guru
Filters?
The Yanmar on my first liveaboard sailboat didn't have a filter as most know it....it was a sump where the oil went through a bunch of tiny metal plates that at intervals, you twisted a handle and whatever collected in those plates fell back into oil pan.
These early Yanmars were used in South America to drive generators at remote villages and ran 10's of thousands of hours and were never shut down according to my mechanic. They just added oil as needed and twisted the lever as recommended by Yanmar.
There are so many misconceptions about engines, oil and filters I stopped believing what I read on the net long ago.
The story on Yanmars is too strange to believe true...but spend some time in the outback and all of a sudden the net seem full of myths toowhen compared to a large segment of the world.
The Yanmar on my first liveaboard sailboat didn't have a filter as most know it....it was a sump where the oil went through a bunch of tiny metal plates that at intervals, you twisted a handle and whatever collected in those plates fell back into oil pan.
These early Yanmars were used in South America to drive generators at remote villages and ran 10's of thousands of hours and were never shut down according to my mechanic. They just added oil as needed and twisted the lever as recommended by Yanmar.
There are so many misconceptions about engines, oil and filters I stopped believing what I read on the net long ago.
The story on Yanmars is too strange to believe true...but spend some time in the outback and all of a sudden the net seem full of myths toowhen compared to a large segment of the world.
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rslifkin
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Having an oil filter is better than not, but not every engine has one. My generator doesn't, for example. Oddly, the air cooled non-marine version of the same base engine does, but they skipped the oil filter on the marine versions for some reason. It does spec somewhat more frequent oil changes than it would likely require with a filter (spec is 50 hours).
