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JTodd
01-06-2007, 15:01
Every time I do a regular oil change, the new oil is almost instantly black. When changing I let the old oil drain for a couple hours before closing it back up and putting in the new. I check the dipstick - looks clean, start truck, let pressure come up then shut it down to check level again. The oil on the stick is as black as what I just drained.

I am using Rotella regular (non-synth).

MTTwister
01-06-2007, 15:05
the remaining oil in the engine has enough soot to do this. I don't think anyone has a way to clean it all out on an oil change. If they do, I'd like to learn.

:) You could pull the engine , disassemble, and boil the block - that's about the only way to get it sterile.

a5150nut
01-06-2007, 16:03
Way back when I used to service a bunch of Detroit 2 cycles, we would periodicly drain and refill with diesel, shut of fuel and crank over a little. Then drain and fill with fresh oil and pull a plug on the front oil gallery to purge dirty oil out of the block befor it returned to the crank case. Part of the problem with our motors is the low amount of oil the hold compared to the Fords. I had a compeny truck 99 Ford F250, and after an oil change it would go 2000 miles before it started to soot up again.

I don't know if our oil coolers drain back or not. There is quit a bit of oil trapped there if they dont. I have thought about trying to find a Lubrifiner 200, they hold about 1 1/2 gallons. This would add more capacity and probably help cooling to some extent. It comes down to volume.

moondoggie
01-06-2007, 16:21
Good Day!

Until a couple years ago, I ran Rotella 10W-30 winter, 15W-40 summer, in all my 6.2's & 6.5's. I had exactly the same as you described.

Then I switched to Synthetic Rotella 5W-40 (in everything I own). It does not anymore turn black immediately, & it never gets as black as it used to. When I visited JK a couple years ago, the dipstick on his 6.5 (since sold) didn't look much different than a gas engine. He'd had a really good rebuild done; might have had those double oil-control rings that effectively don't have a gap too, I don't know. Anywho, the theory was that since the engine was close to blueprinted, greatly reduced blowby.

We should be seeing less of this - I've been told the oil turns black because of the sulfur in the fuel, & that's dropping from ~ 500 ppm to < 15 ppm. Time will tell...

Blessings!

Dvldog8793
01-06-2007, 17:08
Howdy
I use Mobil Delvac1 in the winter and 1300 in the summer. My 1999 gets black within 200miles regardless of oil type. This truck has 10qrt capacity, and iol bypass filter system.
My 1984 6.2 van is stock, I use the biggest possible filters. Every three oil changes I use engine flush and then a clean out with cheapest diesel oil I can find, then I fill it with Mobil 1300(leaks to much to use sythetic) This van will normally go about 800-1000 miles before it looks black.
I think it varies allot between engines, typical use and air quality. I don't think oil brand makes a drastic difference. Diesels will soot up regardless of oil brand/type. I know our 6.5s do not drain any where near to 100%, I would bet there is always close to a quart in the block, cooler, lines, filter neck ect...A little blck will go along ways!
L8r
Conley

xtrempickup
01-06-2007, 17:58
I just did my oil the other day, very black. What is the mileage that most of you are doing your oil change at??? Diesels I read go longer before an oil change, I don't know how true that is, but I went 7K miles the last time and that oil was sooooooo black and nasty I think i'm not letting it go that long again

rustyk
01-06-2007, 23:13
I'm a former fuels and lubes engineer...fresh oil in a diesel turning black is normal. Diesel engine oil that doesn't turn black may or may not be normal. Generally, the only thing one can reliably tell from an oil's color is, well, what color it is.

Mark Rinker
01-07-2007, 08:30
My 6.5s oil turns black instantly, and looks thick and very worn out at 5,000 miles.

In comparison, the DMax oil stays honey colored for the first 3,000 or so, and only gets really black - but not thick - at 8-10,000.

I bet it has something to do with how the oil coolers drain.

Hubert
01-07-2007, 09:02
Yep its the oil cooler, quantity of oil in crankcase, and how easily a little soot can "stain" the color that causes the instant black.

When I did my oil cooler lines alot of oil came out of the cooler when I undid the lines and removed it. I then drained it and set it aside. It turned over without me noticing it and weeped a good bit more oil out after a few minutes.

jerry598
07-24-2007, 07:41
Is there any way to get more of the old oil out of the engine when doing a routine oil change? Like cranking it with the injector pump disconnected? Seems to me that even with an engine flush, and then running cheap oil for a hundred miles or so, then changing it again and putting in good oil would still leave some old oil in the engine, no matter what. If that's true, then changing oil regularly at the recommended interval might be the only thing a person can do without spending alot of time and money and for what result.
Jerry
1995 6.5 turbo

Rhinopkc
07-24-2007, 12:37
Don't worry about it, it's not going to hurt anything. If you're really that worried, get a bypass filter.

Hubert
07-24-2007, 12:57
It does take a little getting use to. I still don't like it but yeah regular oil changes are the best you can do reasonalby. You'll still turn black with a bypass.

I use to be more worried about it and thought some about increasing oil capacity but the more I read the more I learned a lack of lubrication is not a problem for the 6.5. Many that go 200K still have crosshatching in cylinders and the crank/bearing look fine. Even broken down engines and cracked blocks still look good for wear (I have read many times). So must be the oil capacity is ok. I try and change between 3K-5K miles depending on usage (highway/city/towing), time of year, and/or when it seems to be using more between checks. Its good practice to keep oil topped up even if you are only adding a cup or pint at the time.

Good oil upgrades IMHO are a remote mount filter (good double head or bypass filter with big high quality lines), new oil cooler lines, and new bigger oil cooler. Then you should be plenty upgraded for all but the heaviest tow vehicle or most modded engine. Maybe a preluber too but seems overkill for the 6.5 from what I have read.