What Color Should Oil Be On Dipstick for 40 HP YANMAR - 3JH5E - SD 50?

[David Mathis]

For many years, the oil in my Caterpillar 420 hp 3126Bs would be black immediately after the service. The oil was pumped from the hoses attached to the drain plugs. Last year, I borrowed a dip stick tube vacuum device to try to get more oil removed. I was surprised when about 2-3 additional quarts were removed from each engine. They were filled then started. After running for maybe five minutes, the oil was checked. It was the cleanest I'd ever seen it. Remove all of the old oil then the change will appear to have much cleaner oil. At the end of the season it's still black but it looks better after the service.


Also, I keep hearing about how it's important to change the oil after the end of the season so the acids and contaminants don't stay in the engine. I've worked on many engines after long term storage and disassembled one after not being run for at least 20 years. The oil had not been changed before storage. No rust was seen anywhere inside the engine. Unless the engine had gone past the recommended service, I believe the story about the need to change the oil before storage is an old wives tale, passed along based on speculation but with no evidence.

[garyfdl]

Originally Posted by PineyWoodsPete

My '06 Highlander Hybrid V6 w/ 130,000 miles - as clean as baby oil at change, never burns a drop. The '16 Camry Hybrid, at 40,000 mi has burned maybe 1/4L at change time, and takes on a slight honey color.

You have a Highlander and Camry diesel hybrids???

[Compass790]

Originally Posted by JohnHolland

My last boat with MD7A Volvo the oil stayed fairly clear between 100 hour oil changes and.ran.fine. Does clean oil indicate an internal problem?

Whilst i dont know yr engine I wouldnt worry about it, different diesels darken their oil at different rates. I have heard other volvo owners say the same. Personally I'd be happy if it stayed clean.
Also heard some modern auto engine diesels are very slow to darken oil. I think it would depend on multiple factors but probably majorly about how clean burning it is.
It was your last boat so lucky new owner if he doesnt need to buy any volvo parts

[garyfdl]

Originally Posted by David Mathis

Also, I keep hearing about how it's important to change the oil after the end of the season so the acids and contaminants don't stay in the engine. I've worked on many engines after long term storage and disassembled one after not being run for at least 20 years. The oil had not been changed before storage. No rust was seen anywhere inside the engine. Unless the engine had gone past the recommended service, I believe the story about the need to change the oil before storage is an old wives tale, passed along based on speculation but with no evidence.

[gonesail]

Originally Posted by David Mathis

I've worked on many engines after long term storage and disassembled one after not being run for at least 20 years. The oil had not been changed before storage. No rust was seen anywhere inside the engine.

agree. the quality of motor has improved dramatically .. even in the last 10 years.

[PineyWoodsPete]

Originally Posted by garyfdl

You have a Highlander and Camry diesel hybrids???

Since when did Toyota offer diesels in their autos or SUV's in the USA this century? The poster I referred to didn't specify diesel. I do remember a diesel light truck they sold here 35-40 years ago...

[garyfdl]

Originally Posted by PineyWoodsPete

Since when did Toyota offer diesels in their autos or SUV's in the USA this century? The poster I referred to didn't specify diesel. I do remember a diesel light truck they sold here 35-40 years ago...

I don't know, but I wondered, because you guys in Cali seem to get stuff we don't (or rarely) see in the upper midwest (like the Hyundai Ioniq plug-in).

[LittleWing77]

Originally Posted by David Mathis

I keep hearing about how it's important to change the oil after the end of the season so the acids and contaminants don't stay in the engine. I've worked on many engines after long term storage and disassembled one after not being run for at least 20 years. The oil had not been changed before storage. No rust was seen anywhere inside the engine. Unless the engine had gone past the recommended service, I believe the story about the need to change the oil before storage is an old wives tale, passed along based on speculation but with no evidence.

I just finished a one-year marine mechanics course at a reputable college - and they teach it that way. Drum it in, actually.

Part of one of our systems courses was an entire module on engine oil. We even were provided with an oil analysis. You wouldn't believe all the crap suspended in oil that you can see!

Remember, your story above is a single anecdotal case, not enough to provide actual data.

LW77

[garyfdl]

Originally Posted by LittleWing77

I just finished a one-year marine mechanics course at a reputable college - and they teach it that way. Drum it in, actually.

Remember, your story... is a single anecdotal case, not enough to provide actual data.

LW77

LOL so... in your course... did they provide verifiable data detailing why "it's important to change the oil after the end of the season" vs not changing, or, as you say, did they just "drum it" into you? Because if they just drummed it into you, without any verifiable data to back it up, it's anecdotal as well. And that makes your comment a single, second hand, anecdotal case. Just say'n.

I think what we have here is a 'best practices' issue. it is certainly a 'best practice' to change the oil at the end of the season; are going to ruin an engine if you don't? No.

A similar example (and this is more 'single case anecdotal evidence') is the old recommendation by auto manufacturers to change your engine oil every 3000 miles. Fact is, it was based on absolute worst case scenario, and unless you were a NYC taxi / spent hours just idling, it was totally unnecessary. But... it sold a lot of oil. I got this info first hand, 30 years ago, from the chemists at Mobil (who developed Mobil 1). And based on what they told me, started changing every my oil 7500 miles (based on my driving habit's). The vehicles I have had since have all gone over 100,000 miles and several over 200,000. I've never had an engine failure.

[valhalla360]

Originally Posted by cofc

Unless you just changed the oil 5 minutes ago, it's going to be very dark. Like 5,000 mile oil change on your Toyota dark.

Had an old Ford with the 7.3...Running it for a couple minutes before the final level check was enough to turn it black.

Sold the truck at just shy of 300k miles to a couple headed on a cross country trip.

Diesels generate soot and fresh oil picks it up pretty quickly off the surfaces. Doesn't mean the oil isn't doing it's job.

As far as end of season oil change...that's my preferred option when putting an engine into storage. Change it, run it enough to get fully circulated and up to temp and then put it to bed. If I have to do an oil change anyway, I would rather it sit for the winter with fresh oil that is fully stocked with the additives. Doesn't mean the engine will fail the next spring but if it's the same effort, why not?

[LittleWing77]

Originally Posted by LittleWing77

Part of one of our systems courses was an entire module on engine oil. We even were provided with an oil analysis. You wouldn't believe all the crap suspended in oil that you can't see!
LW77

Originally Posted by garyfdl

LOL so... in your course... did they provide verifiable data detailing why "it's important to change the oil after the end of the season" vs not changing, or, as you say, did they just "drum it" into you? Because if they just drummed it into you, without any verifiable data to back it up, it's anecdotal as well. And that makes your comment a single, second hand, anecdotal case. Just say'n.

Sorry, Gary, perhaps I wasn't clear. When speaking of my marine mechanics course, an entire module equates to one week of study - and we did this for both gasoline and diesel engines.

This also included examples of oil samples, oil analysis and - remember Arlo Guthrie's Alice's Restaurant Masacree Movement? - well there were also data and charts and circles and arrows on the back sayin' what each one was...!

Too much to reproduce here.

All of my 4 profs had over 30 years *each* working on marine engines.

So yes, while engine oil varieties and quality have improved, what that also means is their improved ability to clean much more crap out of your boat's engine.

Do NOT let dirty oil sit in the engine for months/years! Run the engine to temp so the oil will be fluid enough to pump out/drain, AND so the crap is suspended in the oil before removal; then change the filter and the oil simultaneously before putting her away for any length of storage.

LW77

[garyfdl]

Originally Posted by LittleWing77

Sorry, Gary, perhaps I wasn't clear. When speaking of my marine mechanics course, an entire module equates to one week of study - and we did this for both gasoline and diesel engines.

This also included examples of oil samples, oil analysis and - remember Arlo Guthrie's Alice's Restaurant Masacree Movement? - well there were also data and charts and circles and arrows on the back sayin' what each one was...!

Too much to reproduce here.

All of my 4 profs had over 30 years *each* working on marine engines.

So yes, while engine oil varieties and quality have improved, what that also means is their improved ability to clean much more crap out of your boat's engine.

Do NOT let dirty oil sit in the engine for months/years! Run the engine to temp so the oil will be fluid enough to pump out/drain, AND so the crap is suspended in the oil before removal; then change the filter and the oil simultaneously before putting her away for any length of storage.

LW77

HEY! I might be old, but I still remember what a mod is in school...
(In fact, I'm so old, I also remember when it was slang for 'modern', the Mod-Squad and also referred to a '60's 'hip' sub-culture into jazz, blues and soul. HOLY CRAP! I'M OLD! )

And I'm sure that the instructor(s) had at least "twenty seven eight-by-ten color glossy pictures with the circles and arrows and the paragraph on the back of each one".
(OABTW - I did that from memory. Though I did check the lyrics to see if I got it right. It's been a while )

BUT

I'm guessing what they didn't/don't have is actual data/evidence that proves leaving the oil, unchanged, in an engine, over a winter, or for several years (and here's the important part) is/was the incontrovertible and conclusive cause of the failure. And here's why I think this: I was a hydraulics engineer for decades. Pulled apart and 'autopsied' more pumps, motors etc than I can remember. And, from my experience, outside of running dry? It is difficult, to the point of impossible, to make an absolutely definitive call as to the point/cause of failure. The best that can be done is a very educated guess, even after looking at things under high powered magnification, metallurgical analysis, etc. So I am applying my knowledge and experience to engines as well.

That said:

"Do NOT let dirty oil sit in the engine for months/years! Run the engine to temp so the oil will be fluid enough to pump out/drain, AND so the crap is suspended in the oil before removal; then change the filter and the oil simultaneously before putting her away for any length of storage."

ABSOLUTELY! This is the 'best practice', and should always be followed.

[noelex 77]

Diesel engine oil can easily go black, but with a newer engine and regular changes it only becomes slightly darker.
This is the dipstick on our engine. It is almost due for an oil change. The oil is 10 months old with about 40 hours from our last oil change.

[garyfdl]

Originally Posted by noelex 77

Diesel engine oil can easily go black, but with a newer engine and regular changes it only becomes slightly darker.
This is the dipstick on our engine. It is almost due for an oil change. The oil is 10 months old with about 40 hours from our last oil change.

How old (how may hours/miles) is that engine?

Why are you changing oil after just 10 mos/40+ hours service?

[noelex 77]

Originally Posted by garyfdl

How old (how may hours/miles) is that engine?

About 270 hours

Originally Posted by garyfdl

Why are you changing oil after just 10 mos/40+ hours service?

Yanmar specify the engine oil should be changed at 12 months. I like to adhere to or exceed the service requirements. Hence at 10 months I anticipate changing the oil reasonably soon, certainly within a couple of months.