Synthetic vs. regular disel oil
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Daddyo
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Many pros only con is price. Synth allows for longer times between changes. Synth is better oil period. You decide.
JAT
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You might want to spend some time reading at this link....
http://www.kleenoilusa.com/pdf/warranty/Cummins-Oil_ServiceBulletin_May-07.pdf
If your engines have EGR's....you need to read it.
Here is what I use in my old Perkins engines...and Cummins approves of it.
Valvoline.com > Products > OEM Endorsed Products > > Valvoline Premium Blue® Extreme Diesel Engine Oil
I really can't see any point in using a synthetic oil....Cummins and other engines manufacturers state the oil change schedule is to be the same for both types of oil, so the only real difference is price.....
NAPA quite often has a sale on the Valvoline Premium Blue....
http://www.kleenoilusa.com/pdf/warranty/Cummins-Oil_ServiceBulletin_May-07.pdf
If your engines have EGR's....you need to read it.
Here is what I use in my old Perkins engines...and Cummins approves of it.
Valvoline.com > Products > OEM Endorsed Products > > Valvoline Premium Blue® Extreme Diesel Engine Oil
I really can't see any point in using a synthetic oil....Cummins and other engines manufacturers state the oil change schedule is to be the same for both types of oil, so the only real difference is price.....
NAPA quite often has a sale on the Valvoline Premium Blue....
Nomad Willy
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99% a waste of money.
sunchaser
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Not true nor recommended by Cummins plus it would void any warranty you may have if you extend beyond mfrs hour limit. Go by the book for recommended oil and change intervals and you won't go wrong. Concentrate on the real maintenance stuff (have you serviced your aftercooler lately?) and you'll be much better off than assuming you'll help your QSL with synthetic oil.
On a common rail or computer controlled newer engine be careful listening to the older engined guys. Once again, boatdiesel.com is your Cummins friend.
Capn Craig
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If you don't intend to stretch the timing of oil changes with extra effective filtration there is no benefit. The synthetics also will do a superior job in starting in frigid temperatures that's no benefit in Forida. It's your money, if it makes you feel good go for it. But you could spend your money more effectively.
Keith
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I'm a big believer in synthetic oil for my truck, but wouldn't put it in an older diesel. After looking at the cost/benefit for even a new diesel, I still wouldn't use it unless it was a workboat, running nearly every day. The way most of us use our trawlers, the dino is just fine. Now if you're full time cruising, I'd certainly use it with a bypass filtration system to reduce the number of changes.
Marine diesel manufacturer's recommend changing the oil every 100-200 hours. This is to remove built up soot, refresh the anticorrosion additives and replace oxidized, degraded petroleum oil with fresh.
The only difference with synthetic is that the latter doesn't happen as much. So to take advantage of that fact and extend oil changes, over the road fleet operators use synthetic oil but monitor soot and additives with routine oil analysis. The analysis is cheaper than the oil change and lets them go hundreds of hours between changes- 500 or more.
But recreational boaters can't or won't do all of the above, so must change their oil as the manufacturer recommends. In that case most of the benefits of synthetic are wasted.
David
The only difference with synthetic is that the latter doesn't happen as much. So to take advantage of that fact and extend oil changes, over the road fleet operators use synthetic oil but monitor soot and additives with routine oil analysis. The analysis is cheaper than the oil change and lets them go hundreds of hours between changes- 500 or more.
But recreational boaters can't or won't do all of the above, so must change their oil as the manufacturer recommends. In that case most of the benefits of synthetic are wasted.
David
FF
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Synthetic is a poor choice for most pleasure boats as the oil drains better (its fuel burn advantage) causing culinder walls to rust sooner.
If the engine MFG ( and local temperature swings) will allow usually a single weight oil gives the longest lasting engine.
If the engine MFG ( and local temperature swings) will allow usually a single weight oil gives the longest lasting engine.
sunchaser
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It depends on the engine and year. My 2003 engines (Perkins Sabre 225/Cat 3056) are book stated at 400 hours with "low" sulfur fuel. Many marine engine books were written when low sulfur fuel didn't exist.
I had a long talk a few days ago with the manager of PNW Cummins Marine about detecting a leak in an aftercooler. He said do it with an oil analysis (yearly for most of us) and I said have a drain valve on the bottom of the cooler to detect salt water on a daily basis. Oil analysis is too late - he agreed. Point being, when cruising, look things over every day, very carefully.
On a side note, Tony Athens just posted on boatdiesel that oil analysis is salve only and he has not seen in his 40 years of marine diesels that oil analysis ("no real benefit") trumps good maintenance.
River Cruiser
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The manual for my Hinos says to use sae30, I use Shell Rotella T. When the engines were built in1986 Dino was pretty much the standard. I think a diesel would get more benefit from a pre-lube system than synthetic & you only buy it once.
Sunchaser:
The 400 hour change interval specified for your engines is interesting.
Sufuric acid produced by sulfur in the fuel, is the a main reason for additives- to neutralize the acid. So with ultra low sulfur fuel, which most of us get at our marinas because it is the only thing that refineries produce today, that problem mostly goes away. (As a corolary, the long standing recommendation to change the oil before winter layup goes away as well for the same reason).
How does your oil look after 400 hours? Black with soot? Ever done an oil analysis to check it?
FWIW the oil in my old naturally aspirated 27 hp Yanmar would turn black in 50 hours or so. The oil in my more modern but mechanically injected Yanmar 370 would take 100 hours or more. I suspect that really modern common rail injected engines can go much longer before soot loading is a problem.
I agree that conservatism and inertia causes most marine engine manufacturers to continue to specify short drain intervals.
David
The 400 hour change interval specified for your engines is interesting.
Sufuric acid produced by sulfur in the fuel, is the a main reason for additives- to neutralize the acid. So with ultra low sulfur fuel, which most of us get at our marinas because it is the only thing that refineries produce today, that problem mostly goes away. (As a corolary, the long standing recommendation to change the oil before winter layup goes away as well for the same reason).
How does your oil look after 400 hours? Black with soot? Ever done an oil analysis to check it?
FWIW the oil in my old naturally aspirated 27 hp Yanmar would turn black in 50 hours or so. The oil in my more modern but mechanically injected Yanmar 370 would take 100 hours or more. I suspect that really modern common rail injected engines can go much longer before soot loading is a problem.
I agree that conservatism and inertia causes most marine engine manufacturers to continue to specify short drain intervals.
David
sunchaser
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DM:
The longest I've gone is about 350 hours when the fall change time kicks in - most of the time about 200 hours. Oil looked sooty after about 250 hours, oil analysis no issues reported as best I recall. Most diesel books assume 70% rated load/fuel burn (and low sulfur feed) for duration of oil change intervals, so since vessel operates at 30% load or so I feel pretty safe.
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FF
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Most engine mfg have engine hours OR time (months) as their specification.
Oil samples may not "save" the engine , but can catch unusual things like a small coolant into the oil leak.
A good history of oil samples will also help at boat sales time
10 years at $15 a test , not hard to recoupe,
Oil samples may not "save" the engine , but can catch unusual things like a small coolant into the oil leak.
A good history of oil samples will also help at boat sales time
10 years at $15 a test , not hard to recoupe,
Nomad Willy
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From what I've read and heard the main reason for changing oil is to remove most of the carbon from the oil. Carbon is said to be an abrasive and a major source of wear in engines.
So considering the above I change my 30W dino oil twice as often but only change the filter every third time. Dino oil is cheap and it's very quick and easy to change oil ..... especially when leaving the filter alone 2/3rds of the time.
Clean oil and easily done w minimal cost.
I would like to get a bypass system. I remember when all cars that had any filter had one.
So considering the above I change my 30W dino oil twice as often but only change the filter every third time. Dino oil is cheap and it's very quick and easy to change oil ..... especially when leaving the filter alone 2/3rds of the time.
Clean oil and easily done w minimal cost.
I would like to get a bypass system. I remember when all cars that had any filter had one.
Anode
Guru
Eric, I don't understand your rational on not changing filters but wanting a bypass system?
The sole purpose of a bypass system or filter is to continue to lubricate if the filter plugs or begins to restrict flow. I've gone back and forth with the bypass filters on construction equipment and trucks. There's convincing arguments on both sides. There are bypass filters for most applications if want to go that route.
I'll continue to change my filters with the oil.
magicbus
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Walmart, by far the cheapest source of Shell Rotella I've found, charges the same for syn as regular so now I run syn.
Dave
Dave
Nomad Willy
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Anode wrote;
"I'll continue to change my filters with the oil."
Not trying to talk anybody into doing anything or say'in my way is best. Just say'in what I do and why.
I'd like the bypass system to filter the oil further than the full flow filter can. The full flow filter is limited to needing to be able to pass all the oil necessary for max rpm. The bypass filter can flow at very low rates and thus can filter out very small particles. They are a little like refining the oil as you cruise along. Not unlike a small re-refiner.
As to the filter changing infrequently I reason that my filters can hold much more "dirt" than what can be collected over a 100 hr period. Changing the oil and changing the filter may be necessary or unnecessary at different intervals. Interestingly changing the oil w/o changing the filter produces oil that looks like new oil .. to my eye. I could, of course drain the filter cartridge and reinstall it but feel I may introduce unfiltered dirt into the engine or get something on the gasket and perhaps cause leaking.
I've mentioned this before and Marin thinks it's nuts and so do many others but I think it works well so why not do it? The only good reason I can think of is that filters are cheap. But one of the biggest things I like about the practice is that it makes oil changing so easy.
"I'll continue to change my filters with the oil."
Not trying to talk anybody into doing anything or say'in my way is best. Just say'in what I do and why.
I'd like the bypass system to filter the oil further than the full flow filter can. The full flow filter is limited to needing to be able to pass all the oil necessary for max rpm. The bypass filter can flow at very low rates and thus can filter out very small particles. They are a little like refining the oil as you cruise along. Not unlike a small re-refiner.
As to the filter changing infrequently I reason that my filters can hold much more "dirt" than what can be collected over a 100 hr period. Changing the oil and changing the filter may be necessary or unnecessary at different intervals. Interestingly changing the oil w/o changing the filter produces oil that looks like new oil .. to my eye. I could, of course drain the filter cartridge and reinstall it but feel I may introduce unfiltered dirt into the engine or get something on the gasket and perhaps cause leaking.
I've mentioned this before and Marin thinks it's nuts and so do many others but I think it works well so why not do it? The only good reason I can think of is that filters are cheap. But one of the biggest things I like about the practice is that it makes oil changing so easy.
RickB
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It is most certainly not a "salve" and rather than "trump good maintenance" it is actually part of a good preventive maintenance program.
Oil analysis is the same a temperature and pressure trending, it gives the prudent owner a means to monitor condition and the rate of change, if any.
Delfin
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Not sure I would agree that the bypass filter's sole purpose is to filter after the OEM filter clogs. Their purpose is to filter the oil to 1 or 2 microns at low flow rates while the OEM handles full flow at 20-30 microns.
Anode
Guru
You are technically correct. My statement was more my "tongue in cheek feeling" about what they do.I don't buy into some of the filter manufactures hype of extending oil change time frames as it's my opinion that more problems arise from oil breaking down than from dirt passing a 30 micron oil filter.
Amsoil makes a system to add a by-pass filter in-line the oem filter system which wouldn't hurt but I certainly wouldn't extend my oil change time intervals.
Boat engine environments are CLEAN compared to off-road trucks and construction equipment.
I don't see any cost/time benefit going beyond the manufactures recommendations. Others may.
Here's a link from Balwin-
Baldwin Filters | Product Highlights
FF
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opinion that more problems arise from oil breaking down than from dirt passing a 30 micron oil filter.
Oil does not "brake down" unless you hugely overheat the oil.It just gets dirty and wears out the additives.
The bypass filter is created on the concept that particles smaller than the full flow filter can catch are still large enough to work as an abrasive. Think Valve Grinding Compound.
On our DD's there is a HUGE difference in oil color , which might be due to particle count.
The 8V71 oil is black on start up with a new DD filter and 7 Gal of new oil. Modern Fullflow spin on.
The 6-71 1950's bypass filter runs clean for almost the first 50 hours after a change.
The Bypass filter uses a commercial filter , not a roll of toilet paper.
Oil does not "brake down" unless you hugely overheat the oil.It just gets dirty and wears out the additives.
The bypass filter is created on the concept that particles smaller than the full flow filter can catch are still large enough to work as an abrasive. Think Valve Grinding Compound.
On our DD's there is a HUGE difference in oil color , which might be due to particle count.
The 8V71 oil is black on start up with a new DD filter and 7 Gal of new oil. Modern Fullflow spin on.
The 6-71 1950's bypass filter runs clean for almost the first 50 hours after a change.
The Bypass filter uses a commercial filter , not a roll of toilet paper.
RickB
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sunchaser
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Before one's knickers get in a twist, I've been involved with tens of thousands of oil analyses on fleet and genset engines. I'm a believer. Oil sampling when done on a regular programmed basis is a key tool for determining engine rebuild time, measuring metal wear and monitoring lesser issues when speaking of real workhorse applications. We used dummie samples, different labs to compare, referees, fleet history and OEM advice to insure what we saw was really an event rather than a random spike. On a 100 + unit fleet ranging from sporadic use forklifts to 24/7 haulers it takes a real pro (I'm not one) managing the data and systems to monitor what was going on.
But an oil analysis every now and then on a few hundred hour per year (at most) toy boat engine is not as important as how the real things have been taken care of to prevent the oil from showing baddies.
Oil analysis does no harm for us on trawler forum. But does it do any good? For those of you who detected and prevented a problem or justified a rebuild, in advance of failure, due to an oil analysis done in the fall or spring each year, please post about that event. I don't recall seeing one on TF and very seldom on boatdiesel. Everything I have seen on TF includes the following areas:
- I'm losing coolant
- My engine temperatures are up
- Where did my RW pump impeller vanes go
- How do I use Ridlyme
- I have bubbles in the fuel
- My filters are plugging with gunk
- I have visible water in my oil
- My oil smells like diesel
- I have visible oil in the coolant
- I have soot in my coolant
- I have black, white or grey exhaust
- I have rust all over my mixing elbow
- What causes hydrolocking
- I heard a noise and then an hour later my engine stopped
- I'm burning 1 gallon per hour of oil in my 35 year old DD
- ETC
Oh, Tony Athens you say. Go to his posting #49252 with the last entry made on Feb 3 titled "MTU Oil Analysis Opinion"
Part of his comment is, "put a random oil analysis where it belongs - at the bottom of the list of things to worry about."
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sunchaser
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Most if not all lower priced syns are a blend and a marketing tool. A blend of what is the question. Unless the blend is approved/agreed/stated by the Cummins book, why try to save $$ on an expensive boat and motor by getting a cheap non specified oil? The notion that a little syn is better than no syn is incorrect.
Nothing the matter with Walmart branded and recommended oils. I buy my DELO 400 15/40 at Costco for about 1/2 the cost of the local yard.
Nomad Willy
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All this synthetic talk is a waste of time. Pure synthetic is one thing but a "blend" is whatever ..... has a tad bit of synthetic within. Like dry cereal that says it's got real raspberries in it. You can eat a bowl, look at the package where it says boldy that there is raspberries in it and notice that you didn't notice any raspberries or even taste any. But you bought the box of cereal.
I said 99% of us don't need synthetic. I may have been wrong. It may be 97% of us. The only thing I can think of that would get your lube oil hot enough to need synthetic is on an extremely high performance engine. John Baker may (just may) have one. Turbos get hot and if one regularly ran a HP turbodiesel at 85+ % of it's output they could possibly need syn lube oil. if one's oil isn't breaking down from severe heat (300 degrees or so) one dosn't need syn oil ... or benefit in any meaningful way.
Premium fuel is another way to get people to buy a higher quality product. But in the "premium" fuel the only premium part is the higher octane and if you don't need it "premium" fuel does you no good at all but they sell lots to people that think it does. Premium just sounds better. And in this high tech world now "synthetic" sounds better and people buy into it.
As to the by-pass filter I see some confusion in previous posts. It's an auxiliary system. It is independent of the installed system on one's engine other than the fact that it uses the oil pump to move the oil that flows through the by-pass filter. As far as I know it just takes a very small amount of oil from the main source, filters it and dumps it into the oil pan or someplace that leads there.
I said 99% of us don't need synthetic. I may have been wrong. It may be 97% of us. The only thing I can think of that would get your lube oil hot enough to need synthetic is on an extremely high performance engine. John Baker may (just may) have one. Turbos get hot and if one regularly ran a HP turbodiesel at 85+ % of it's output they could possibly need syn lube oil. if one's oil isn't breaking down from severe heat (300 degrees or so) one dosn't need syn oil ... or benefit in any meaningful way.
Premium fuel is another way to get people to buy a higher quality product. But in the "premium" fuel the only premium part is the higher octane and if you don't need it "premium" fuel does you no good at all but they sell lots to people that think it does. Premium just sounds better. And in this high tech world now "synthetic" sounds better and people buy into it.
As to the by-pass filter I see some confusion in previous posts. It's an auxiliary system. It is independent of the installed system on one's engine other than the fact that it uses the oil pump to move the oil that flows through the by-pass filter. As far as I know it just takes a very small amount of oil from the main source, filters it and dumps it into the oil pan or someplace that leads there.
Something that I don't believe was mentioned here is the claims of better fuel economy with synthetic oil. I suppose it's possible, but I've decided to stick with conventional oil for my boat.
I buy my Shell Rotella oil at Walmart for about $12 per gallon.
I buy my Shell Rotella oil at Walmart for about $12 per gallon.
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Eric and Chip, I think y'all might be talking about two different things??? I believe Eric is talking about a way to filter oil and Chip is talking about a backup system...
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