Oil flush?

Bruh44

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BX2380
Mar 29, 2023
78
17
8
North Carolina
I changed my oil last fall. Almost immediately after changing it, it was black again. So I’m changing it again today. I’m adding a little Oil with the drain plug still off. There’s a good amount of black coming out still.
do you all flush your oil out? If so, what do you used? I’m not going to flush it now, but I may do it this fall.
 

PoTreeBoy

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Mar 24, 2020
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I changed my oil last fall. Almost immediately after changing it, it was black again. So I’m changing it again today. I’m adding a little Oil with the drain plug still off. There’s a good amount of black coming out still.
do you all flush your oil out? If so, what do you used? I’m not going to flush it now, but I may do it this fall.
We're talking engine oil, right? It's not unusual for diesel engines to 'black' the oil quickly. My 20 year old Kubota with 2000+ hours keeps the oil pretty clear, unless I work it hard. Our 30 year old Ford's oil turns black within 10 to 15 hours and it's not working very hard turning a 6' Bushhog. It has about 700 hours on it.

The black is mainly soot from burning fuel oil, I think. It's still necessary to change the oil at the recommended interval. If it bugs you, change more frequently, but no flush is needed.
 
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mcfarmall

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Kubota M5660SUHD, Farmall C
Sep 11, 2013
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Additionally, the quick blackening of the oil is the detergent package grabbing the soot particles and keeping them in suspension so the filter can trap them. Indicates your using decent oil.
 
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MapleLeafFarmer

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Lots incl. B and L kubotas
Dec 2, 2019
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I have never flushed a diesel engine.

That said though I do use good quality diesel rated oils and change it no less than every 2 years on litle used diesels or 200 hrs whatever comes first.

Has your tractor been neglected or improper fluids used? If not it shouldn't need a flush IMHO.
 
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Flintknapper

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L2350DT
May 3, 2022
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My 28 yr old L2350DT will black the oil within 6-8 hrs of use after an Oil and Filter change. I change both (Oil and Filter) every 100 hrs use.

Have always considered the blackening (for this engine D1102) a normal thing. It runs like a top still. 1300 hrs.
 

JonM

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Kubota Grand L6060
Nov 29, 2024
56
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wisconsin
I changed my oil last fall. Almost immediately after changing it, it was black again. So I’m changing it again today. I’m adding a little Oil with the drain plug still off. There’s a good amount of black coming out still.
do you all flush your oil out? If so, what do you used? I’m not going to flush it now, but I may do it this fall.
welcome to diesel engines.

they all do it even my truck. its normal.

if your concerned send an oil sample to blackstone labratories for analysis
 

Runs With Scissors

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L2501 TLB , Grappel, Brush Hog, Box Blade, Ballast box, Forks, Tiller, PH digger
Jan 25, 2023
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Just so you have a reference, this is a pic of my trucks dipstick. 5.9l Cummins with 280K

I changed the oil 3 days ago, so it's got about 30 miles on it, and its "blacker than the Ace of Spades."

IMG_3690.JPG


As the others have pointed out, it's perfectly normal.
 
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TerryKing

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B7100HST-D
Aug 18, 2024
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When I bought my old B7100HST the oil was really black. I planned to use Rotella T6 in it. I had some other Rotella. I drained the original, filled with the Other? Rotella, added 1/2 can of "Sea Foam" and ran that for about an hour. Drained (pretty black), replaced oil filter, filled with Rotella T6 and it looked clean and stayed quite clean looking for maybe 25 hours. Now looking somewhat dark and will change at 75 hours soon.

With the T6 5W40 and a inline heater in the lower radiator hose it started instantly at zero F temperatures this past winter.
 
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Hugo Habicht

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G1900
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Ok, thank you all for the info. I won’t be doing a flush.
Stupid question: did you drain the oil when hot? Otherwise a small bit of old oil could be left. And yes, the remaining oil will be black from the soot.

If oil changes had been neglected there could be a build up of sludge, so changing with a shorter interval may be beneficial. Otherwise just keep changing the oil as per manual and use oil for Diesel engines and it'll be fine. And always use a new oil filter.
 
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Bruh44

Member

Equipment
BX2380
Mar 29, 2023
78
17
8
North Carolina
When I bought my old B7100HST the oil was really black. I planned to use Rotella T6 in it. I had some other Rotella. I drained the original, filled with the Other? Rotella, added 1/2 can of "Sea Foam" and ran that for about an hour. Drained (pretty black), replaced oil filter, filled with Rotella T6 and it looked clean and stayed quite clean looking for maybe 25 hours. Now looking somewhat dark and will change at 75 hours soon.

With the T6 5W40 and a inline heater in the lower radiator hose it started instantly at zero F temperatures this past winter.
This is what I meant by flushing it. Just running seafoam for maybe 1-2 hours tops.
I’ve done it in my truck, it worked pretty well.
Tge engine was warm, not hot when I changed it. I had run it for a while but was doing some other work on it for a couple hours, then ran it for maybe 2-3 minutes before the change.
 

The Evil Twin

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L2501, LA526,
Jul 19, 2022
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You are better off changing the oil more often than putting anything except oil in your crankcase. If there is indeed sludge the detergents in the oil will break it down. Seafoam will change the viscosity and possibly induce wear.
Speaking from a sludge perspective. You dont want it breaking up too quickly. It could migrate and plug up an oil passage.
 
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