Hello all, I am new to this "diesel buzz" but from what i know about all diesel engines is their ability to turn oil "tar black" even after a fresh oil change. BUT since owning my first diesel recentely after changing the oil right after ownership to rotella 15w40 (CJ4) AND 5,000 miles later..i am not seeing this "tar black" oil like expected. Could it differ from engine to engine? What about oil to oil?? I figure not seeing "tar black" oil after 5,000 of mixed driving that at least maybe my piston rings must be sealed well...not allowing combustion gases to contaminate oil? Chime in all!!
New to diesel engines...
- Thread starter Ponch
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Originally Posted By: nfs480
When you drain the crankcase it will look tar black, trust me.
Yup.
Also, how new is it? Is it a fairly new rig or an older one?
When you drain the crankcase it will look tar black, trust me.
Yup.
Also, how new is it? Is it a fairly new rig or an older one?
It differs greatly from engine to engine.
A lot of the Direct Injection super diesels of today show very low soot, and you can see through the oil to the dipstick like you would a petrol.
My old BJ42 would leave a new oil/black streak line up the dipstick as you filled it with new, and after 5 mins, was black as paint...and left ingrained soot in your skin for multiple washes after a change.
A lot of the Direct Injection super diesels of today show very low soot, and you can see through the oil to the dipstick like you would a petrol.
My old BJ42 would leave a new oil/black streak line up the dipstick as you filled it with new, and after 5 mins, was black as paint...and left ingrained soot in your skin for multiple washes after a change.
dnewton3
Staff member
Rest assured that the color of the oil has nothing with it's ability to "protect" your engine.
As a matter of fact, I WANT my oil to look black. That indicates that the oil is doing it's job with both the anti-agglomerates (dispersants) and detergents.
Sure, it's nice to see oil (nearly) clean for a while, but the reality is that oil will darken fairly quickly from use. Once it does, it's likely still a viable product. Also, know that there is always some residual oil in the engine that will quickly darken the new oil. I often chuckle when guys let the last few drips roll out after a 1/2 hour of draining, in some vain attempt to "get every last drop" out, but they don't stop to consider what is left in places the oil won't drain from with gravity, and only can be pushed out via pressure. Also, there are some crankcase pans that have "pools" (for a lack of a better word) that will not drain unless you had the vehicle on an EXTREME incline. My Dmax engine is one example. There is a small reverse-hump in the front of the pan that has no exit for oil other than the cyclical exhange of constant use. Yet some owners will drip-drip-drip in a vain effort to remove all oil, when there must be almost 1/2 a quart sitting at the front of the pan that has zero ability to drain via gravity!
Bottom line: don't worry about the color of the oil. It's the condition of the oil that's important.
If you want to know the true condition of the oil, only a UOA will tell you that, and perhaps a PC analysis as well.
As a matter of fact, I WANT my oil to look black. That indicates that the oil is doing it's job with both the anti-agglomerates (dispersants) and detergents.
Sure, it's nice to see oil (nearly) clean for a while, but the reality is that oil will darken fairly quickly from use. Once it does, it's likely still a viable product. Also, know that there is always some residual oil in the engine that will quickly darken the new oil. I often chuckle when guys let the last few drips roll out after a 1/2 hour of draining, in some vain attempt to "get every last drop" out, but they don't stop to consider what is left in places the oil won't drain from with gravity, and only can be pushed out via pressure. Also, there are some crankcase pans that have "pools" (for a lack of a better word) that will not drain unless you had the vehicle on an EXTREME incline. My Dmax engine is one example. There is a small reverse-hump in the front of the pan that has no exit for oil other than the cyclical exhange of constant use. Yet some owners will drip-drip-drip in a vain effort to remove all oil, when there must be almost 1/2 a quart sitting at the front of the pan that has zero ability to drain via gravity!
Bottom line: don't worry about the color of the oil. It's the condition of the oil that's important.
If you want to know the true condition of the oil, only a UOA will tell you that, and perhaps a PC analysis as well.
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Actually some of the newer DI style diesels aren't bad for turning it black-my 6.0 doesn't get black until 4,000 miles on the oil-but the older IDI diesels, unless in perfect condition, will turn it black FAST. Fortunately, newer oil has a higher soot capacity, and can handle it. When I first got my '82 300D, the PO had used Castrol GTX for overly long OCI intervals (12-13K), and the first couple oil changes the oil came out in CHUNKS! That's when you know you waited too long!
My diesel will turn the oil black in just a few miles.
What kind of vehicle did you get?
What kind of vehicle did you get?
The newest diesel engines have better injection systems for exhaust emission reasons. A side effect of this is much less soot in the crankcase. Gasoline basically burns more cleanly than diesel fuel which leaves a sooty residue, but the modern injection systems narrow this gap a lot.
The color of the diesel lube doesn't matter a lot, as well said above. I've run a lot of industrial diesels and sent their oil to the testing lab. Soot-black oil still lubricates fine and tests fine. There is a point where the soot content in the oil becomes excessive, but small diesels should never reach that point with properly operating equipment and normal oil drain intervals.
The color of the diesel lube doesn't matter a lot, as well said above. I've run a lot of industrial diesels and sent their oil to the testing lab. Soot-black oil still lubricates fine and tests fine. There is a point where the soot content in the oil becomes excessive, but small diesels should never reach that point with properly operating equipment and normal oil drain intervals.
Thanks everybody! My vehicle is a 2007 silverado HD classic body style. Duramax of course....with 35,000 miles on her....a "pup" as far as diesel age!
I had a 66 2 ton truck with a 2 stroke detroit diesel in it and that was by far the worst I ever saw, oil would be black after idling for a minute. My dodge isn't bad at all on the dipstick but the oil will be black but not bad when I drain.
I wish I would have kept that ole truck, it was quite a unique little engine, inline 4 cylinder.
I wish I would have kept that ole truck, it was quite a unique little engine, inline 4 cylinder.
Those DD 2-stroke diesels were "self-changing" on engine oil-I'm actually looking at a boat that has 2 4-71TA motors in it, not sure if I'm up to that big of a challenge!
Originally Posted By: Ponch
Thanks everybody! My vehicle is a 2007 silverado HD classic body style. Duramax of course....with 35,000 miles on her....a "pup" as far as diesel age!
That's a good truck, you got the latest duramax engine made without the diesel particulate filter, so you don't have to decide whether to remove it and lose your warranty or keep it on and deal with the fuel dilution and poor fuel economy.
Thanks everybody! My vehicle is a 2007 silverado HD classic body style. Duramax of course....with 35,000 miles on her....a "pup" as far as diesel age!
That's a good truck, you got the latest duramax engine made without the diesel particulate filter, so you don't have to decide whether to remove it and lose your warranty or keep it on and deal with the fuel dilution and poor fuel economy.
Just keep an eye out for the oil level going up by itself (which means the infamous Duramax injector disease has struck!). I keep a close eye on the 6.0 and the Dodge CR motors, myself.
Originally Posted By: bullwinkle
Just keep an eye out for the oil level going up by itself (which means the infamous Duramax injector disease has struck!). I keep a close eye on the 6.0 and the Dodge CR motors, myself.
Not a problem in the LBZ duramax from 07. It has redesigned valve covers so that if the injectors leak they don't drain into the sump, they just leak down the side of the block. Not as many injector problems on the late duramax engines anyway.
Just keep an eye out for the oil level going up by itself (which means the infamous Duramax injector disease has struck!). I keep a close eye on the 6.0 and the Dodge CR motors, myself.
Not a problem in the LBZ duramax from 07. It has redesigned valve covers so that if the injectors leak they don't drain into the sump, they just leak down the side of the block. Not as many injector problems on the late duramax engines anyway.
Why worry about diesel fuel dilluting my oil now???? it is an "oil" right??? ha! I know better than that!
Originally Posted By: bullwinkle
Those DD 2-stroke diesels were "self-changing" on engine oil-I'm actually looking at a boat that has 2 4-71TA motors in it, not sure if I'm up to that big of a challenge!
Forget the oil leaks ... can you stand the noise?
Those DD 2-stroke diesels were "self-changing" on engine oil-I'm actually looking at a boat that has 2 4-71TA motors in it, not sure if I'm up to that big of a challenge!
Forget the oil leaks ... can you stand the noise?
Originally Posted By: AITG
Originally Posted By: bullwinkle
Those DD 2-stroke diesels were "self-changing" on engine oil-I'm actually looking at a boat that has 2 4-71TA motors in it, not sure if I'm up to that big of a challenge!
Forget the oil leaks ... can you stand the noise?
If it is an fishing boat go for it. The offshore guys in FL swear by the Detroits for raising fish. Supposed to have something to do with the low frequency hum or engine noise.
Originally Posted By: bullwinkle
Those DD 2-stroke diesels were "self-changing" on engine oil-I'm actually looking at a boat that has 2 4-71TA motors in it, not sure if I'm up to that big of a challenge!
Forget the oil leaks ... can you stand the noise?
If it is an fishing boat go for it. The offshore guys in FL swear by the Detroits for raising fish. Supposed to have something to do with the low frequency hum or engine noise.
Originally Posted By: 3311
Originally Posted By: AITG
Originally Posted By: bullwinkle
Those DD 2-stroke diesels were "self-changing" on engine oil-I'm actually looking at a boat that has 2 4-71TA motors in it, not sure if I'm up to that big of a challenge!
Forget the oil leaks ... can you stand the noise?
If it is an fishing boat go for it. The offshore guys in FL swear by the Detroits for raising fish. Supposed to have something to do with the low frequency hum or engine noise.
Just like women and Harleys?
Originally Posted By: AITG
Originally Posted By: bullwinkle
Those DD 2-stroke diesels were "self-changing" on engine oil-I'm actually looking at a boat that has 2 4-71TA motors in it, not sure if I'm up to that big of a challenge!
Forget the oil leaks ... can you stand the noise?
If it is an fishing boat go for it. The offshore guys in FL swear by the Detroits for raising fish. Supposed to have something to do with the low frequency hum or engine noise.
Just like women and Harleys?
Originally Posted By: Steve S
Originally Posted By: 3311
Originally Posted By: AITG
Originally Posted By: bullwinkle
Those DD 2-stroke diesels were "self-changing" on engine oil-I'm actually looking at a boat that has 2 4-71TA motors in it, not sure if I'm up to that big of a challenge!
Forget the oil leaks ... can you stand the noise?
If it is an fishing boat go for it. The offshore guys in FL swear by the Detroits for raising fish. Supposed to have something to do with the low frequency hum or engine noise.
Just like women and Harleys?
You got it!
Originally Posted By: 3311
Originally Posted By: AITG
Originally Posted By: bullwinkle
Those DD 2-stroke diesels were "self-changing" on engine oil-I'm actually looking at a boat that has 2 4-71TA motors in it, not sure if I'm up to that big of a challenge!
Forget the oil leaks ... can you stand the noise?
If it is an fishing boat go for it. The offshore guys in FL swear by the Detroits for raising fish. Supposed to have something to do with the low frequency hum or engine noise.
Just like women and Harleys?
You got it!
Originally Posted By: Ponch
Hello all, I am new to this "diesel buzz" but from what i know about all diesel engines is their ability to turn oil "tar black" even after a fresh oil change. BUT since owning my first diesel recentely after changing the oil right after ownership to rotella 15w40 (CJ4) AND 5,000 miles later..i am not seeing this "tar black" oil like expected. Could it differ from engine to engine? What about oil to oil?? I figure not seeing "tar black" oil after 5,000 of mixed driving that at least maybe my piston rings must be sealed well...not allowing combustion gases to contaminate oil? Chime in all!!
Thats one thing thats always puzzled me.
I had never seen a diesel with clean oil in it until one time I bought an old used '73 Ford 3000 diesel farm tractor.
I thought the old boy had just changed the oil in it before I bought it. But after running it a while, the oil was still clear.
I don't know what oil the previous owner had used in it, but I always used Rotella 15w40, and it never turned black between changes for the several years I had it.
Now I have a '89 Case/IH 385 diesel, and the oil never gets black in it either. So this makes me think that there must be at least some older diesel farm tractors out there, that are the same way.
Hello all, I am new to this "diesel buzz" but from what i know about all diesel engines is their ability to turn oil "tar black" even after a fresh oil change. BUT since owning my first diesel recentely after changing the oil right after ownership to rotella 15w40 (CJ4) AND 5,000 miles later..i am not seeing this "tar black" oil like expected. Could it differ from engine to engine? What about oil to oil?? I figure not seeing "tar black" oil after 5,000 of mixed driving that at least maybe my piston rings must be sealed well...not allowing combustion gases to contaminate oil? Chime in all!!
Thats one thing thats always puzzled me.
I had never seen a diesel with clean oil in it until one time I bought an old used '73 Ford 3000 diesel farm tractor.
I thought the old boy had just changed the oil in it before I bought it. But after running it a while, the oil was still clear.
I don't know what oil the previous owner had used in it, but I always used Rotella 15w40, and it never turned black between changes for the several years I had it.
Now I have a '89 Case/IH 385 diesel, and the oil never gets black in it either. So this makes me think that there must be at least some older diesel farm tractors out there, that are the same way.
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