Diesel Engine Oil Change Frequency?

[botanybay]

Originally Posted by michaelratinter

We change the oil and filter in the lake boat (Yanmar) before putting her on the hard each fall. The ocean boat (Perkins 4.236) oil and filter change every 100 engine hours (8 quarts!)

Yup and My M90 runs 13 quarts!

Then again, we are lucky, I get all sorts of grief complaining about13 quarts when my powerboat friends are triple that!

[Aliciano]

I think that is regular change about 100 hours, if I not wrong

[rwidman]

Originally Posted by UNCIVILIZED

Guys, it really varies from engine to engine as to what's the best. ................. Newer engines run at higher RPM's, have much more closely machined parts tolerances, better alloys & heat/chemical treatments of same. Etcetra, etc. And as such they often will run well on thinner oils (lighter weight) than designs that are 20 or 50 years old...........

And this is why we go by the engine manufacturer's recommendations.

[Oceansailor]

On my Yanmar 4JH4-TE the recommended oil change is after 250 hours. I baby it and change the oil earlier. Normally in the range 100-150 hours.

Once I met a fellow cruiser that owned a trucking company. They regularly did oil analyses on the trucks to find out how long they could run the trucks on the same oil as it was a big expense in the company.

He owned the same Yanmar engine as I did. He had off course done the same thing with the Yanmar engine. The answer was that the oil had lost quite a lot of the performance at 250 hours. The recommendation from was to change sooner. (150-200) Instead he manufactured an adopter plate that made it possible to use a oil filter with twice as much filter area. I do not remember how many hours he got out of the oil with a larger filter. But it was quite substantial.

[MarkSF]

One advantage of a remote oil filter kit is the ability to use a larger filter. It also bumps the oil capacity up a little.

[a64pilot]

Be careful with the remote adapters. I had one that blew the O ring where the adapter attaches to the engine, twice.
I like the idea of a larger filter, and especially with being able to mount it right side up so you could change it with no spilling, and pre fill it on oil change, but blowing the O ring twice soured me on it.
I think if you can possibly find one made by Yanmar that would be a different story.

[MarkSF]

Originally Posted by a64pilot

Be careful with the remote adapters. I had one that blew the O ring where the adapter attaches to the engine, twice.
I like the idea of a larger filter, and especially with being able to mount it right side up so you could change it with no spilling, and pre fill it on oil change, but blowing the O ring twice soured me on it.
I think if you can possibly find one made by Yanmar that would be a different story.

Interesting point. I am looking at the one I installed, Wix 24730.

Wix Filters - Product Catalog search results

Look at the O ring. It's in a groove, and then there are flat surfaces outside, and inside, the ring. If both those surfaces are metal to metal against the mating surface on the engine, there's no way the O ring can come out. But if the OD of the adapter is larger than the OD of the mating surface on the engine, it seems possible that it could. That means you have to be very careful about matching the ODs and IDs of both mating surfaces.

The problem I had was oil leaking from the taper threads where the hose adapters screw in. I first used a semi-setting gasket paste, and that leaked. Second time I used a fully setting gasket paste, and that worked fine.

[botanybay]

Originally Posted by MarkSF

Interesting point. I am looking at the one I installed, Wix 24730.

Wix Filters - Product Catalog search results

Look at the O ring. It's in a groove, and then there are flat surfaces outside, and inside, the ring. If both those surfaces are metal to metal against the mating surface on the engine, there's no way the O ring can come out. But if the OD of the adapter is larger than the OD of the mating surface on the engine, it seems possible that it could. That means you have to be very careful about matching the ODs and IDs of both mating surfaces.

The problem I had was oil leaking from the taper threads where the hose adapters screw in. I first used a semi-setting gasket paste, and that leaked. Second time I used a fully setting gasket paste, and that worked fine.

I especially like any filter which is compatible in a pinch with a PH8A, those old Ford style filters are available anywhere on the planet and are better than nothing in a pinch. A large number of oversized filters also use this interface.

[MAJICDAN]

The 1974 engine manual for my 6.354 Perkins said to change the oil and filter every 200 hours.
I have almost 11,000 hours on my motor.
Of course, today's synthetic oils, such as "ÄMSOIL", changed everything that we thought we knew. Amsoil says to change the factory oil filter at normal intervals and that their oil is good for 600 hours unless you do testing. I was concerned, since I had so many hours on the motor, so I did testing every two hundred hours. I finally changed it at 1000 hours even though the testing came back fine.

[Kenomac]

OK, the oil and filters have been changed on both the generator and engine, just like every prior season. But I'm still thinkin' that most people don't do it annually, and choose not to respond on threads like this. With the exception of a few power boats in this marina, I'm guessing the vast majority of engines are lucky to be changed even once every three years.

[Cadence]

Originally Posted by Kenomac

OK, the oil and filters have been changed on both the generator and engine, just like every prior season. But I'm still thinkin' that most people don't do it annually, and choose not to respond on threads like this. With the exception of a few power boats in this marina, I'm guessing the vast majority of engines are lucky to be changed even once every three years.

Probably true but what does a few qts of oil and a filter cost? Seems like a minor investment.

[steve77]

Originally Posted by Kenomac

OK, the oil and filters have been changed on both the generator and engine, just like every prior season. But I'm still thinkin' that most people don't do it annually, and choose not to respond on threads like this. With the exception of a few power boats in this marina, I'm guessing the vast majority of engines are lucky to be changed even once every three years.

Well, lest I be taken for someone who chose not to participate because I don't change my oil, I'll chime in.

We have the 4JH3-HTE and change the oil and filter every 100 hours, or as close to it as I can. Prior to reading this thread I did not make a special effort to change it at the end of the season, but you guys have made a believer of me, so that will now be the case.

Ken, to your point, I'm sure that some people are not changing their oil annually, but I would hesitate to say that "most" of them do not. I would think that for boats that are being actively sailed, the majority of the owners do a pretty good job of maintaining regular oil changes. Not all, but most of them. Just my opinion.

Cheers!

Steve

[Mike Banks]

Well. If one looks at oil as a chemical compound with specific characteristics which allow it to adhere to metals and provide a low friction interface--it is only impurities produced in combustion or admitted through the engine itself, and chemical changes in the oil that are likely to degrade it.

Which is why many modern ships using diesel propulsion and low-grade fuels have an oil recirculating system that allows them to keep the same oil for the lifetime of the engine, topping it up as required.

These systems involve filtering, heating and distilling off impurities, then re-condensing, then further filtration and cooling down again to engine temperature before re-admission to the engine sumps or oil tank of the dry sump system.

Since small vessels do not have such a system--it is essential to change the oil. Ideally we should change it every so many hours of engine use--my 4wd diesel engine is recommended to change the oil every ten thousand kilometers, provided that their recommended synthetic oil is used. If one assumes an average speed of sixty kilometers an hour for driving, that equates to about 200 hours or so. Since boat engines probably work a bit harder than vehicle engines, but operate at a fairly constant RPM, this could probably be extended to 3oo or maybe even 400 hours--but for my money I change mine every two hundred engine hours and I used the Yanmar oil as recommended in the service manual.

Which brings me to an interesting point--dealing with old engine oil. It should be possible, using a small high pressure hydraulic pump and a temperature controlled pressure vessel to filter and distill and re-generate one's oil in the same way that the oil regeneraters on commercial ships operate.

When I worked in the timber industry we used our old oils by allowing the sludge to settle, (which took ages) then siphoning off the oil using wicks, into a receptacle below. Gravity did it. We used this oil to lubricate our chain-saws (we added some diesel oil and detergent--Comprox as I recall) and the rest was used in our sawmills to lubricate axles, bearings etc. Very little of it was wasted and almost none of it was ever dumped.

So--I have an oil change coming up. I think I will hang on to it--I have a few things for which I will be needing some oil.

[captainstubbie]

Just my 2 cents. With the limited use that you have I would just change it a nd the filters at the end of every season and say good enough. It's cheap insurance for the next year and the life of the engines. It is my understanding the oil never breaks down, it is simply the additives and the particles that are added to it...

[a64pilot]

As far as oil breaking down, it does. However the additive packages go first, the broader spread the weight for Dino oil, the more exotic the additive package, and the shorter the life. One good reason to run a straight weight oil in a boat, cause temps don’t vary much and multi vis oil is simply not required, for all but a very few.
However for the average lowish RPM, normally aspirated Marine Diesel, it’s unlikely you will ever break down the oil. For example my old 4JHE at 40HP is I believe the same displacement as the 100 HP turbo is. Which one do you think stresses the oil the most?
Anyway those type of motors need the oil changed due to the oil being laden with soot, soot is carbon, and carbon is very abrasive.
Decades ago Amsoil and a few others sold high bypass filters, meaning that they had a very fine filter that only filtered a small portion of the oil, but as it was done continuously, all the oil went through the very fine filter pretty often, that would mean if you ran a high grade of synthetic oil you could have very long change intervals.
However the bypass oil filter systems have pretty much gone away, as have pre_oilers. Reason is average consumer is ignorant and doesn’t really care about taking care of their engine, they will likely buy another boat, automobile whatever before five years have passed anyway.
Remember new boats sell to the type of person that buys a new boat, and the majority of them do not keep a boat for decades and tens of thousands of hours or engine operation.

Ken is right, most boat owners are ignorant and do not take care of their engines like they were trying to get 10,000 hours out of it, cause they won’t own it then.
I just took my Daughters Prius in for its 200,000 fluid changes, Toyota dealer here in Brunswick Ga had never changed the fluid in the “transaxle”. They said it was sealed, never needed changing. It doesn’t if you consider the life span of an automobile to be 100,000 miles