Which Engine Oil Do You Use (& Why)

[BandB]

There seems to be a lot of thought given to this issue making it quite complicated in the minds of some. But yet it seems simple to me. So, I just have one question.

What will be wrong about just using what the manufacturer recommends or recommended?

[MarkSF]

Well, one thing is that oil technology has moved on. The manual for my Universal 5424 was written in 1980. Oil has changed quite a bit since then....for example, using a 10w40 or 15w40 vs. a straight 30 weight oil will give better cold starting (and protection during the critical warm-up phase) and still give better protection when hot.

[BandB]

Originally Posted by MarkSF

Well, one thing is that oil technology has moved on. The manual for my Universal 5424 was written in 1980. Oil has changed quite a bit since then....

And what is wrong with using the oil that was recommended for it in 1980? Is it going to do harm to the engine to continue using that oil?

Engines and oil have changed. Everything has.

[a64pilot]

Dockhead,
A lot of statements, don't know where to start and I'll miss a few I'm sure. For one thing I'm now on the IPad using some kind of app so it's goofy.

First oil is like anchors or religion, sort of. In that your not going to convert ones that just don't want to believe.
As far as syn oil damaging anything, I've heard that for the last thirty years, and you know what, I just don't believe it, I've never seen one single case of that and I have looked. I don't mean second hand, my cousin type of thing.
As far as moisture in a non running engine all I can do is to tell you to research cam failures in Lycoming engines.
TBN is not a measure of how base the oil is, it's a measure of the reserve alkalinity or how much additive is left, yes a high TBN is useful for extended OCI if that is your goal, it is not my goal. I believe there is more than one way to get a high TBN, so saying one oil with a high TBN hurt something, so all high TBN oil is bad, you just can't make that statement. I do believe since the adoption of ULSD, the TBN requirement may be less, you may be right there.
Syn oil is sort of a misnomer, sort of like saying something is plastic, as not all plastics are the same all Syn oils are not the same either, you just can group them all together.
Maybe going onto Shells website and looking up what they claim for the Rotella T6 might help.
SOAP, or spectrographic Oil Analysis Program is a useful tool, and if I were running my engine 50 hours a week, I might consider it, but with an OCI of six months and varying engine hours, I doubt it would be useful.
Perhaps I am wasting my money, but heck it's my religion you know.
I overhauled my IO540W1A5D aircraft engine at 2000 hours, recommended TBO, and when I sent all the hard parts off for inspection, they all met NEW limits, not serviceable limits, but new limits, use of Exon elite oil and frequent OCI is what made that happen as well as properly warming it up and cooling it down etc.
About manufacturers recommendations, first they are like the recommended daily allowance of vitamins, they are the MIN of which you must have, not the best, but the min. Marketing has a lot to do with it also, let a manufacturer spec a high grade of oil and all the sales people of the competition try to say there is something wrong with that engine, theirs doesn't require special oil.
Plus unless you have a newer engine, it's very likely you can't find the oil that is specified for your engine as that spec has been superseded, so you may need to do a little homework to see if your favorite brand of oil meets the old spec, chances are if you use a good brand it does.
Heck I run an air filter on my engine too, not the screen they come with, but an air filter. Does it need one, probably not, but if my alt belt starts slipping I want a filter there to catch the dust and if you look at my airconditioner filter, there is dust on a boat.

[Wotname]

Originally Posted by BandB

And what is wrong with using the oil that was recommended for it in 1980? Is it going to do harm to the engine to continue using that oil?

Engines and oil have changed. Everything has.

Another reason not to use the manufacturer's recommend oil is that it has often become unavailable in some (many?) parts of the world.

It you can't source it, you can't use it

From what has been posted here, this seems to be a problem for some and not for others.

For myself living in a small capital city of a first world country, the Yanmar recommended oil is only obtainable from a few sources and I had to hunt it down. OK, now I know where to look, I can get it but it wasn't easy to find it in the first place. I can buy oil for my car, truck, tractor, mower, chainsaw etc etc from just about anyplace that has a population of 2 or more but I have to travel for an hour or more to buy the recommended oil .

That is why many have used non-recommended oils.

This thread has been very helpful for me in understanding how widespread the problem is and what is the best solution. FWIW, my best solution was to hunt down the recommended oil rather than take the easy road of buying the most current API rated diesel oil that was available anywhere.

[JPA Cate]

A64pilot wrote, "there is dust on a boat."

There sure is! Seems really unfair to me! Even on long offshore passages, there is dust in air and it gets EVERYWHERE!

Sorry for the digression.

Reading this thread so far is pretty interesting, and I understand much better why Wotname started it.

When the fuels have changed and the manufacturer's recommended oils are no longer available, and given that some engines seem vulnerable to assaults by some synthetic oils, 'tis a puzzlement.

Ann

[Wotname]

Well I spoke too soon
The state supplier of a CD rated oil doesn't actually stock it and understandably isn't interested in getting 5 litres every year just for one customer.

I have found 20W-50 CD which isn't that far from the recommended 15W-40 and it is just possible that I might be able to find a single grade SAE30 CD oil.

The oil salespeople are suggesting to use a CF rating (but no later that CF).

I have asked the Yanmar distributors in Australia for their comment and will advise if they reply.

[Dulcesuenos]

Originally Posted by BandB

And what is wrong with using the oil that was recommended for it in 1980? Is it going to do harm to the engine to continue using that oil?

Engines and oil have changed. Everything has.

Fuels have changed, hence the need for a better oil in even in an older engine to compensate. Or so I have read,,,,,,,
As for synthetics, what better oil for an engine running 75% load for hours on end. Cars run 25% or less most of their life's. Without the use of group 2+, and group 3,4 oils and manufacturers still extended service intervals on engines with group 2 oils. My 2013 dodge charger has a SI of 8500 miles on conventional. Almost 3 times that of the past vehicles. . Synthetic oil isnt designed to extend life, its designed to improve performance, lubrication, protection, cleaning and most importantly fuel economy there by reducing emissions, that "go 10000-25000 miles is marketing gimmicks from mobil and amsoil and once you read thru their bs of disclaimers you realize its not really Good idea

Sent from my LG-LS980 using Cruisers Sailing Forum mobile app

[Wotname]

Originally Posted by Wotname

...........
I have asked the Yanmar distributors in Australia for their comment and will advise if they reply.

And they have responded - within a day - that's good service

Their answer was simple, use the Yanmar branded oil which unsurprisingly is almost the same as what is recommended in the handbook.

The Yanmar branded oil (in Australia at least) is a mineral oil, single weight (SAE 30) with an API rating of CD. The only difference to that in the handbook is that the handbook recommends a multi grade of 15W-40. Give the local air temps here, the single weight is just fine IMO.

The good news is that it isn't outrageously priced. Just under $45 for 5 litres which is comparable to reasonable quality car engine oil around here.

Still an hour plus drive to get it but that is doable. I sleep easily tonight

[a64pilot]

I'm sure everyone already knows this, but oil for gasoline engines is not the same as oil meant for Diesels, even if the weight is exactly the same, the specs are different

[Wotname]

Originally Posted by a64pilot

I'm sure everyone already knows this, but oil for gasoline engines is not the same as oil meant for Diesels, even if the weight is exactly the same, the specs are different

And I'm sure you are correct

But as you also know, many oils have a duel API classification; a Sx and a Cx so can be used either way

[malbert73]

Originally Posted by Wotname

And they have responded - within a day - that's good service

Their answer was simple, use the Yanmar branded oil which unsurprisingly is almost the same as what is recommended in the handbook.

The Yanmar branded oil (in Australia at least) is a mineral oil, single weight (SAE 30) with an API rating of CD. The only difference to that in the handbook is that the handbook recommends a multi grade of 15W-40. Give the local air temps here, the single weight is just fine IMO.

The good news is that it isn't outrageously priced. Just under $45 for 5 litres which is comparable to reasonable quality car engine oil around here.

Still an hour plus drive to get it but that is doable. I sleep easily tonight

+1

I get it if you're not close to a yanmar dealer, but that's what I do. Who cares if it's $10-15 more per change on a $15K engine.
Peace of mind using manufacturer spec'd oil. Why reinvent the wheel, or worse yet, damage it?

[BandB]

Originally Posted by malbert73

+1

I get it if you're not close to a yanmar dealer, but that's what I do. Who cares if it's $10-15 more per change on a $15K engine.
Peace of mind using manufacturer spec'd oil. Why reinvent the wheel, or worse yet, damage it?

Also in the small quantities you're using, the oil can be shipped so it doesn't have to be driving there.

[Wotname]

Originally Posted by Wotname

And they have responded - within a day - that's good service

Their answer was simple, use the Yanmar branded oil which unsurprisingly is almost the same as what is recommended in the handbook.

The Yanmar branded oil (in Australia at least) is a mineral oil, single weight (SAE 30) with an API rating of CD. The only difference to that in the handbook is that the handbook recommends a multi grade of 15W-40. Give the local air temps here, the single weight is just fine IMO.

The good news is that it isn't outrageously priced. Just under $45 for 5 litres which is comparable to reasonable quality car engine oil around here.

Still an hour plus drive to get it but that is doable. I sleep easily tonight

Originally Posted by malbert73

+1

I get it if you're not close to a yanmar dealer, but that's what I do. Who cares if it's $10-15 more per change on a $15K engine.
Peace of mind using manufacturer spec'd oil. Why reinvent the wheel, or worse yet, damage it?

UPDATE:


Just made the trip to the local Yanmar dealer to pick up the Yanmar branded oil only to find the packaging says SAE 30 CF/CF2. When I quizzed the supplier, he said "that's funny, it used to say SAE 30 CC/CD". We had a look at the stock and found the 1 litre bottles (older stock) marked CC/CD while the 5 litre containers (newer stock) were CF/CF2. He called the Aussie HQ and their response was something like "Don't worry, it's what we use now".

So I'm over oil; I think I will throw in anything that is handy in the future - the engine will probably die of some other neglect anyway.

Life is hard for the pedantic and the particular - perhaps I should go sailing and relax some.

Oil - I've surrendered to modernity