Oil Change Schedule

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jdscott3

Member
Joined
Apr 30, 2017
Messages
18
Location
US
Vessel Name
Harvest Moon
Vessel Make
1981 Grand Banks Classic 42’
I’ve searched and not found info on this, how many hours between oil changes is recommended? I’ve a John Deere 6068 if that matters. Thanks
 
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You should get the manual for your engine from the dealer or J.D. themselves.
THere will be other info that will be important such as valve settings, firing order, coolant requirements, oil requirements, and of course changeout intervals for oil and coolant and more.

Most engine mfgrs. will recommend somewhere between 100 and 200 hours or yearly , whichever is first.

You might also look on this site for the manual in the PDF files. This screen, LH side menu.


I will also suggest that in addition to the Owners and Mtce. manual you get the Parts Book for your engine and even the Shop Manual. These manuals, the marine versions, will get harder to access every year, They are often not the same as the on the road , construction or Ag engines.

Even if you do not do the work it will be a boon to you and your mechanic if you have those manuals.

When you order them you will need the specific model and the serial number to ensure the correct manuals.
 
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NOTE: For 6068SFM50 engines, the oil and filter is changed at 500 hour/12 month intervals. See next section.

During break-in, change engine oil and filter for the first time before 100 hours maximum of operation, then every 250 hours thereafter.

If John Deere PLUS-50® engine oil and a John Deere oil filter are used, the oil and filter change interval may be extended to 375 hours.

NOTE: If the above recommendations are not followed, the recommended oil and filter change interval is every 250 hours/ or 6 months. If diesel fuel with a sulfur content greater than 0.05% (500 ppm) is used, reduce the oil and filter change interval by 100 hours.

OILSCAN is a John Deere sampling program to help you monitor machine performance and identify potential problems before they cause serious damage. OILSCAN kits are available from your John Deere dealer. Oil samples should be taken prior to the oil change. Refer to instructions provided with kit.

This comes out of the John Deere service manual for 6068 engines.
 
Most boat owners change the oil every 100 hours or thereabouts, but its probably an overkill. A few TF members just get there oil sampled every 10 hours, and run it up to 500 hours and the oil is still looking good.

I change mine twice a year, unless a put on more than 500 hours.
 
"I will also suggest that in addition to the Owners and Mtce. manual you get the Parts Book for your engine and even the Shop Manual. These manuals, the marine versions, will get harder to access every year, They are often not the same as the on the road , construction or Ag engines".


Superb advice
 
NOTE: For 6068SFM50 engines, the oil and filter is changed at 500 hour/12 month intervals. See next section.

During break-in, change engine oil and filter for the first time before 100 hours maximum of operation, then every 250 hours thereafter.

If John Deere PLUS-50® engine oil and a John Deere oil filter are used, the oil and filter change interval may be extended to 375 hours.

NOTE: If the above recommendations are not followed, the recommended oil and filter change interval is every 250 hours/ or 6 months. If diesel fuel with a sulfur content greater than 0.05% (500 ppm) is used, reduce the oil and filter change interval by 100 hours.

OILSCAN is a John Deere sampling program to help you monitor machine performance and identify potential problems before they cause serious damage. OILSCAN kits are available from your John Deere dealer. Oil samples should be taken prior to the oil change. Refer to instructions provided with kit.

This comes out of the John Deere service manual for 6068 engines.


I ran our Deere engines (4045 and 6090) to the same published guidelines EXCEPT where did you get the 500 hr interval in your first statement? Is that a typo, and meant to be 250 hrs? I've never seen a Deere spec for more than 250 hrs other than using their magic oil, and then it's only up to 350 hrs.


Worth noting is that there is no spec alteration for synthetic vs traditional oil. The change interval is the same. Those are the mfg guidelines, so the best starting point. From there, there is endless discussion about all the variations that you can do, if you are so motivated.
 
I have a JD 4045TFM75 as my propulsion engine. After the 1st thousand hours had worked my way up to 250 Hour oil changes. Wear metals started climbing past Blackstone labs safe range, but still within JD's internal white paper acceptable range. Cut the oil change time in half (125 hours) and saw an immediate difference. After 2 oil changes, wear metals were back within Universal Averages for Blackstone. Haven't decided whether I will increase the time interval to 200 hours or not. My 2 takeaways are oil analysis is everything and just because the manufacturer says you can, doesn't mean it will always be best in your application.

My engine cruises at 1,500 RPM, at <50% of load for that RPM, and I use JD Plus 50 II 15W/40 oil.

Ted
 
I have never understood the strategy of frequent oil sample analysis to extend the interval between oil changes. It seems like a lot of trouble to gain an extra 100 hours or so between changes. Oil sample with each oil change? Sure.

I have a John Deere 4045AFM85. Recommended oil change interval is 250 hours. So at 250 I spend $90 and 30 minutes doing what John Deere recommends. Simple. Even if I had twins, changing the oil is not that big of a deal.

Of course there are environmental benefits to extending the interval. One must weigh those against the benefits of following manufacturer's guidelines and avoiding any problems with erroneous sample data.
 
I have never understood the strategy of frequent oil sample analysis to extend the interval between oil changes. It seems like a lot of trouble to gain an extra 100 hours or so between changes. Oil sample with each oil change? Sure.

I have a John Deere 4045AFM85. Recommended oil change interval is 250 hours. So at 250 I spend $90 and 30 minutes doing what John Deere recommends. Simple. Even if I had twins, changing the oil is not that big of a deal.

Of course there are environmental benefits to extending the interval. One must weigh those against the benefits of following manufacturer's guidelines and avoiding any problems with erroneous sample data.

Do you occasionally lab test the oil at oil change? I only ask as I was doing the same interval as you and it didn't work out well for me.

Ted
 
Each engine and each marine install is going to be different. Some engines are loaded right at a sweet spot where they burn very clean. Some are loaded where the oil gets high soot content in short hours.

The engine mfr does not know how the engine is getting operated, and has to guess a decent change interval.

You can be pretty certain that if the mfr specs 250hr, and you change it at 250, you are probably good. They spec that for close to worst case, and I doubt many of us operate like that.

The sampling is the way to go. I've done a few samples over the 4000-odd hrs on my Cummins 450. Usually sample around 200hrs into a change. Oil lab says the oil is about 1/3rd through its useful life. I'm not comfortable going 600hr on oil, so I change it at 250-300hr, depending on what trips might be ahead. Cummins spec is 250hr. I don't like starting a trip on 200hr oil.

My engine does run in a "happy spot", about 1900-2000rpm, 9-11gph, about 200hp, right about where a continuous rated version is. So that helps.

On some sporties where engines run HARD, the oil is a mess at 100-150hr. No way would I run those to 250.

I don't buy the "once a year" thing if boat runs year round. It does make sense on boats that store for the winter, change it right before storage.

Many oil change specs from the mfr's persist from before the introduction of low sulfur diesel. With high sulfur, the acids formed would deplete the base additives and that would force a change. With low S fuel, that is hardly a problem. Low S fuel also (somehow) lessens soot creation. Not sure why, but that is my experience.

Doing a sample every now and then will tell you if the chosen change interval makes sense or not.
 
Ted, Yes, I do oil analysis with each change. My engine is young, but so far no issues.

I am surprised that the wear protection in the JD oil apparently breaks down during the 250 hour interval. Especially since you run at a fairly light load. Any thoughts on why that happens? And would using a synthetic help?
 
Given most of us are running well below full load and less than 200 hours per year, has anyone experienced an engine failure due to lubrication issues when following the "book."

To support Ski's lower soot with ULSD fuels, my "book" states up to 400 hours with ULSD and lesser hours as S level in fuel increases. Engines are Perkins Sabre 225TI / Cat 3056.
 
Given most of us are running well below full load and less than 200 hours per year, has anyone experienced an engine failure due to lubrication issues when following the "book."


Good question. I have never, ever heard of an engine that failed because the wrong oil was used, or because it wasn't changed often enough. And I've seen some pretty abused engines.
 
Ted, Yes, I do oil analysis with each change. My engine is young, but so far no issues.

I am surprised that the wear protection in the JD oil apparently breaks down during the 250 hour interval. Especially since you run at a fairly light load. Any thoughts on why that happens? And would using a synthetic help?
I don't know what happened. The dealer is old school, deals with waterman and not really a oil analysis guy unless there's an issue. He is very helpful and forwarded me an internal white paper on wear metal levels for all their engines. The normal range numbers are scary high but based on a 10,000 life expectancy before rebuild. According to JD's numbers, I was well within allowable limits. I installed the motor and am already at 2,400 hours, so really want to exceed the 10,000 life expectancy.

Would probably go to 100 hour oil changes before synthetic. Clearly clean oil works. It's just a matter of determining the right change interval.

Ted
 
I ran our Deere engines (4045 and 6090) to the same published guidelines EXCEPT where did you get the 500 hr interval in your first statement? Is that a typo, and meant to be 250 hrs? I've never seen a Deere spec for more than 250 hrs other than using their magic oil, and then it's only up to 350 hrs.


Worth noting is that there is no spec alteration for synthetic vs traditional oil. The change interval is the same. Those are the mfg guidelines, so the best starting point. From there, there is endless discussion about all the variations that you can do, if you are so motivated.

I have never seen an engine identified as a 6068sfm50. Since it is called out as an exception i’ve always assumed it was an engine with a giant oil pan or some other additional oil reservoir. I don’t know why it is an exception.
 
ON Any used but new to me boat changing the oil (and all fluids) is first task.

I would run perhaps 20-25 hours (a couple of long days) and change out the oil and filter again.

Not that costly , 5-8 gallons of oil and a filter or two , is hardly a big deal.

Like most insurance , hopefully it was not needed.
 
I have never seen an engine identified as a 6068sfm50. Since it is called out as an exception i’ve always assumed it was an engine with a giant oil pan or some other additional oil reservoir. I don’t know why it is an exception.




It's just an older model. Appears to be mid 2000s Would that fit?


Things like oil pans alternators, and other configuration variations are all detailed in the option code sticker on the engine. It's along list of numbers, and each is an option code for some aspect of the engine. You can look them up in the parts book to see what each is, and exactly what you have in your engine as delivered from the factory.
 
Some of this stuff is not intuitive.

Heat is good for oil and cooks out the water vapor. Cool oil is not good.

Loads are good for engines and oil. Better ring sealing and less blowby so less oil contamination.


Sometimes the relationship between friction and velocity is counter-intuitive also.
 
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